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Biochem Block 3
KYCOM Block 3
918
Biochemistry
Graduate
10/26/2012

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Term
What is intracellular signaling
Definition
Signals arise within the cell due to allosteric regulation and substrate concentrations
Term
What is intercellular signaling
Definition
Signaling between differs cells, coordinate developmental and survival activities
Term
What are the types of intercellular signaling
Definition
Direct contact, synaptic signaling, endocrine signaling
Term
What occurs during direct contact signaling
Definition
Signals sent between layers of cells at periphery of tissues via gap junctions
Term
When is direct contact signaling used
Definition
Wen cells are not in good contact with vessels
Term
What does direct contact signaling share with the other cells
Definition
mRNA, cell cycle regulators, evidence of pathogen invasion, etc
Term
What occurs in synaptic signaling
Definition
Signaling is carried out using neurotransmitters
Term
What occurs in endocrine signaling
Definition
Hormone is released in one location and travels to a receptor in another location
Term
War is the function of endocrine signaling
Definition
Coordinate multiple tissues, regulate and coordinate metabolism
Term
I general, what is a g-protein coupled receptor classified as
Definition
Integral membrane protein
Term
What is a g-protein coupled receptor specific
Definition
Because it can only interact with one ligand
Term
How is a g-protein coupled receptor structured? How many units does it have?
Definition
It has 7 transmembrane domains
Term
What does it mean when said that a g-protein is heterochromatic
Definition
It has 3 subunits: alpha, beta, gamma
Term
Wen is the G protein alpha subunit located when it is inactive
Definition
At the beta gamma subunit docking station
Term
How can G protein be stimulatory or inhibitory?
Definition
It can interact with the G protein coupled receptor to inhibit the process (Gi) or it can interact with the adenylyl cyclase to stimulate the process (Gs)
Term
When the Alpha subunit binds adenylyl cyclase, where does it bind
Definition
On the guanosine nucleotide
Term
What qualifies the alpha subunit of the G protein to be stimulator or inhibitor
Definition
If it is working with a stimulating G protein it is stimulating (Gas) when working with a inhibiting G protein it is and inhibitor (Gai)
Term
Once protein kinase A is activated, how does it actually effect the cell
Definition
It phosphorlyates target proteins which regulates flow of ions across membranes, regulates metabolic pathways using enzymes, acts as DNA binding protein and promotes or inhibits gene expression
Term
What are the steps in the first path we learned to initiate cellular response to intercellular signals
Definition
1. Ligand binds G protein coupled receptor
2. Receptor changes conformation on its inner cellular surface
3. G protein that is interacting with the receptor changes conformation
4. G protein changes GDP to GTP
5. G protein alpha subunit dissociates from the beta gamma dock
6. Alpha subunit changes conformation of adenylyl cyclase
7. Adenylyl cyclase generates cAMP using free ATP
8. cAMP activates protein kinase A by binding to its 2 regulatory subunits and release the two catalytic subunits
9. Protein kinase A phosphorlyates target proteins
10. Alpha subunit hydrolysis GTP to GDP
11. Alpha subunit dissociates from adenylyl cyclase
12. Alpha subunit docks with beta gamma dock
Term
In general, what is a adenylyl cyclase considered to be
Definition
An integral membrane enzyme
Term
In general, what is cAMP considered to be
Definition
Secondary messenger
Term
When a ligand binds a G protein coupled receptor, what changes occur in the G protein
Definition
It changes conformation changing GDP to GTP, the alpha subunit dissociates from the beta gamma subunit dock and goes off to find adenylyl cyclase
Term
What tools do adenylyl cyclase need to generate cAMP
Definition
G protein alpha subunit, ATP
Term
How does cAMP activate protein kinase a
Definition
It binds to its two regulatory subunits and causes the release of its two catalytic subunits
Term
What hydrolysis GTP back to GDP
Definition
G protein alpha subunit
Term
Way are the three ways to stop the first path of intercellular signaling
Definition
Remove the hormone (or other extra cellular signaling molecule), dephosphorlyate proteins, hydrolysis of cAMP
Term
What do protein phosphatses do
Definition
Hydrological lay cleave phosphate esters and remove effector proteins that are phosphorlyated by protein kinase
Term
What do cAMP phosphodiesterases do
Definition
Hydrolysis of cAMP, cleaves the phosphodiester bond turning it into 5'-AMP which is inactive
Term
Wy is removing the extra cellular signaling molecule not the most effective way of stopping a intercellular signaling chain
Definition
The effect can still keep going inside the cell
Term
Explain the process of cholerae infection
Definition
1. It enters the gut and releases cholera toxin
2. Toxin enters the epithelium and is endocytosed, only the elephant subunit enters the cell
3. Alpha subunit is clipped
4. Alpha subunit interacts with ADP ribosylation factor
5. The factor activates adenylyl cyclase permanently
6. Lots of cAMP is made so lots of protein kinase is made
7. Ca is released from the ER opening Cl channels
8. Cl drags positive ions (Na) and water out of the cell into large intestines
9. This much water cannot be absorbed so it causes dirreaha and denydration
Term
How is a cholerae infection treated
Definition
Water and electrolytes to replace the water lost, there isn't a problem absorbing the water just retaining it
Term
What causes the build up of water in the intestines in a cholerae infection
Definition
Ca release opens Cl channels and drags after and positive ions and water into the large intestines
Term
What are the steps in the second path we learned to initiate cellular response to intercellular signals
Definition
1. Ligand binds receptor
2. Receptor conformation changes activates Gq protein
3. Gq protein releases GDP and binds GTP
4. Gaq subunit detaches and activates phospholipid C
5. Phospholipid c cleaves the lipid bi layer into IP2, IP3, DAG
6. IP3 binds ER activating Ca channels releasing Ca into cytosol
7. DAG stays in the membrane, activating protein kinase C with the help of Ca
8. Ca and protein kinase C work together as a secondary messenger to turn on phosphorylation proteins
Term
Where is phospholipase C located
Definition
In the cell membrane
Term
What does phospholipase C do when activated
Definition
Cleaves the lipid bi layer into IP2, IP3, and DAG
Term
If in the liver and the ligand is epinephrine, what intracellular signaling process is activated, how does it happen
Definition
Glycogen degradation when epinephrine binds a1 adrenic receptor. Calcium binds cal moulin, this new complex changes conformation of enzymes in metabolism
Term
how do organs of metabolism communicate
Definition
nervous system, circulating substrates, hormones
Term
in metabolism, what do hormones signal for
Definition
to store or use energy
Term
what is coordination of the metabolism primairly regulated by
Definition
insulin and glucagon
Term
what is coordination of the metabolism secondairly regulated by
Definition
epinepherine and norepinepherine
Term
where is insulin produced
Definition
beta cells of the islets of langerhan in the pancreas
Term
what is insulin stored in
Definition
secretory granules
Term
where is glucagon produced
Definition
alpha cells of the islets of langerhan in the pancreas
Term
what type of effetor is insulin
Definition
anabolic
Term
what type of effector is glucagon
Definition
catabolic
Term
in general what does insulin affect, what does this cause
Definition
it affects glycogen, TAGs, and proteins. promotes glucose uptake
Term
in general, what does glucagon affect, what does this cause
Definition
affects glucose release from the liver. it causes gluconeogenesis and glycogenolysis
Term
what stimulates insulin to be released
Definition
increased blood glucose, amino acids, peptide hormones, glucagon decreases
Term
what do peptide hormones have to do with insulin
Definition
when produced due to response to food ingestion, they cause insulin to be released
Term
what stimulates glucagon
Definition
decreased amino acids, epinepherine
Term
what inhibits insulin
Definition
decrease in glucose or amino acids (fasting), increase in epinepherine
Term
what can causes increases in epinepherine in the body
Definition
stress, trauma, exercise
Term
what effect does epinepherine have on the body
Definition
increases glucagon, decreases glucose, affects mobilization of glucose from the liver and fatty acids from adipose
Term
in general, what inhibits glucagon
Definition
increasing glucose or insulin levels
Term
what are the types of glucose receptors
Definition
insulin sensitive and insulin insensitive
Term
what type of tissues are insulin insensitive receptors located
Definition
in tissues that require uptake of glucose but do not have a role in blood sugar regulation
Term
what tissues have insulin insensitive receptors and use active transport
Definition
epithelia of intestine, renal tubules, choroid plexus,
Term
what tissues have insulin insensitive receptors and use facilitative transport
Definition
RBC, WBC, lens of eye, cornea, liver, brain
Term
what type of transport do tissues with insulin sensitive receptors use
Definition
facilitated
Term
what tissues have insulin sensitive receptors
Definition
most tissues: skeletal muscle, adpipose..
Term
what is the general cause of hypoglycemia
Definition
low glucose causes elevated glucagon and epinepherine and low insulin
Term
what are the adrenergic symptoms of hypoglycemia
Definition
anxiety, papitation, sweating, tremor
Term
what causes the adrenergic symptoms of hypoglycemia
Definition
epinepherine, ACTH, and growth hormone release from the hypothalamus in response to decreased glucose levels
Term
what are the neuroglycopenia symptoms of hypoglycemia
Definition
headache, confusion, slurred speech, seizures, coma, death
Term
what causes the neuroglycopenia symptoms of hypoglycemia
Definition
impaired delivery of glucose to the brain
Term
what is the treatment of hypoglycemia
Definition
resolved in minutes of glucose intake
Term
what is the main worry of someone who is experiencing hypoglycemia
Definition
CNS only fuel is glucose, without glucose for too long nerves die, could cause death
Term
what does transient hypoglycemia cause
Definition
cerebral dysfunction
Term
what are the types of hypoglycemia
Definition
insulin injected, postparandial, fastine
Term
what type of patients usually have insulin injected hypoglycemia
Definition
diabetes patients
Term
what are symptoms of insulin injected hypoglycemia
Definition
unconsious, no coordiinated swallow reflex
Term
how do you treat insulin injected hypoglycemia
Definition
subcutanous or intramuscular glucagon injection
Term
what is the second most common hypoglycemia
Definition
postparandial
Term
what causes postparandial hypoglycemia
Definition
exaggerated insulin release following a meal
Term
how do you treat postparandial hypoglycemia
Definition
auto corrects itself, eat frequent small meals
Term
what is the most rare hypoglycemia
Definition
fasting
Term
what are the most serious symptoms involved in fasting hypoglycemia
Definition
neuroglycopenia
Term
what causes fasting hypoglycemia
Definition
low liver glucose production, fasting and alcohol, pancreatic tumors that make lots of insulin
Term
what are the three paths you could take to try and inhibit glucagon signaling
Definition
regulate glyconeogenesis, increase glycogen storage, decrease glycogen storage
Term
how can glycogenesis be regulated to stop glucagon signaliing
Definition
dephosphorlyate glycogen synthase
Term
how can glycogen storage be increased to stop glucagon signaliing
Definition
add insulin which decreases cAMP with phosphodiesterase and activates protein phosphatase 1. dephosphorlyate glycogen synthase to activate it
Term
how can glycogen storage be decreased to stop glucagon signaliing
Definition
glycagon and epinepherine induce cAMP production, protein kinase A phosphorlyates glycogen synthase, phosphorlyated glycogen synthase is inactivated
Term
in gulcagon signaling once the associated enzymes are phosphorlyated, what occurs in the liver
Definition
break don of glycogen and increased gluconeogenesis, ketogenesis, amino acid uptake to make carbon skeletons for gluconeogenesis
Term
in gulcagon signaling once the associated enzymes are phosphorlyated, what occurs in the adipose
Definition
activation of lipolysis, free fatty acids are used by the liver to make acetyl coenzyme A to do ketogenesis
Term
what are the steps of glucagon signaliing
Definition
1. glucagon binds glucagon receptor
2. receptor activates g-protein which activates adenylyl cyclase
3. adenylyl clcyase generates cAMP
4. protein kinase phosphorlyates and activates metabolic enzymes
Term
what are the steps of insulin signaling
Definition
1. insulin binds receptor tyrosine kinase on the insulin receptor
2. tyrosine kinase phosphorlyates beta subunit of insulin receptor and insulin receptor substrates
3. substrates promote activation of protein kinases and phosphatases
4. proteins affect gene expression, cell metabolism, and cell growth
Term
once insulin binds to the membrane, what changes occur in the membrane
Definition
insulin promotes recruitment of insulin sensitive glucose transporters in so more transporters come to the membrane and increase insulin mediated glucose uptake
Term
what changes occur in the membrane after insuliin levels are reduced
Definition
glucose transporters are taken out of the membrane and stored in the cell as endosome
Term
after signaling, what does insulin cause to happen to carbohydrate metabolism (explain what goes on in each tissue)
Definition
glycogen synthesis in the liver, increases glucose transporters in muscle (GLUT-4), in adipose it causes glycerol-3-phosphate synthesis for TAG production
Term
after signaling, what does insulin cause to happen to lipid metabolism
Definition
takes fatty acids out of the blood to increase TG synthesis in adipose, uses glucose to make glycerol-3-phosphage and FA for TAG synthesis
Term
after signaling, what does insulin cause to happen to protein metabolism
Definition
stimulates amino acid uptake by most tissues and protein synthesis
Term
How do beta cells sense changes in glucose levels, explain the process
Definition
Sugar is phosphorlyated by glucokinase and converted to ATP, the increase in ATP closes K channels, depolarizing the membrane, calcium voltage gated ion channels open, calcium flows in, fusion and secretion of insulin granules that are inside the cell
Term
what is the purpose of a metabolic map
Definition
shows big picture of meatbolic pathways, helps you visualize intermediates, helps you figure out what happens if you block a step
Term
what does catabolism mean
Definition
degredation or break down of complex molecules
Term
what are examples of what catabolism might break down
Definition
proteins, polysaccharides, lipids, CO2, NH3, H20
Term
what is anabolism
Definition
synthesis. reactions form complex products from simple precursors
Term
what is an example of a reaction of anabolism
Definition
glucose to glycogen
Term
what role does catabolism play in metabolism
Definition
captures energy from ATP, NADH, or NADPH via degregation of energy rich fuels, allows us to reduce complex molecules from storage or diet into useful building blocks for other compounds
Term
what does catabolism do to proteins
Definition
breaks them into amino acids
Term
what does catabolism do to carbohydrates
Definition
breaks them into monosaccharides
Term
what does catabolism do to fat
Definition
breaks it into fatty acids and glycerol
Term
once catabolism makes amino acids, monosaccharides, fatty acids, and glycerol, in general, what happens to them
Definition
they are converted to acetylyl CoA, put into the TCA cycle which oxidizes it, and makes fatty acids, cholesterol, ketones, and other complex molecules
Term
what does anabolism do to amino acids
Definition
makes proteins
Term
what does anabolism need to work
Definition
energy: ATP or reduced compounds (NADH or NADPH)
Term
what is the time span of the well fed state
Definition
2-4 hours after eating
Term
what is another word for the well fed state
Definition
absorptive state
Term
what basic changes occur in the well fed state in the body
Definition
1. increase in blood glucose, AA, TAG (as chylomicrons) from the food
2. pancreas releases insulin secretion and decreases glucagon release
3. glycogen and TAG synthesis increases to replenish fuel storage
4. protein synthesis increased to replenish what was used in fasting (protein isnt stored)
Term
what factors control metabolism (control the enzymes)
Definition
avability of substrates, allosteric regulation, covalent modification, induction or repression of enzyme synthesis
Term
in what pathways of metabolism does gene expression regulation occur
Definition
in ones that are only active in certian physiological conditions, influences enzyme avability not how well the enzyme works
Term
on what molecules does covalent modification of enzymes occur
Definition
-OH or SER, THR, or TYR
Term
at what point do allosteric enzymes usually regulate
Definition
rate limiting steps
Term
what organ is considered to be the nutrient distribution center for the metabolism
Definition
liver
Term
what does the venous drainage of the portal vein do for the nutrients in the body
Definition
it makes them all enter the liver first to be stored, rerouted, or metabolized
Term
in general, what is the function of the liver in metabolism
Definition
allow smoothing of broad fluxuations of nutrients. stores what you have too much of or breaks down molecules to get the nutrients you need more of
Term
what is the only organ that releases glucose
Definition
liver
Term
what can the liver do with glucose
Definition
release it when blood glucose is low, store it if it is high
Term
what type of insulin receptors does the liver have
Definition
GLUT 2 non-insulin sensitive
Term
what happens to glucose once it enters the liver cell
Definition
it is phosphorlyated by glucokinase
Term
what can the liver do with glycogen
Definition
increase glycogen synthesis to store sugars, glycolysis
Term
describe the carbohydrate metabolism of the liver when well fed
Definition
when glucose is taken it it causes glycogen synthesis, increases activity of hexos monophosphate pathway providing NADPH and NADH for FA synthesis, increases glycolysis, decreases glyconeogenesis
Term
describe the role of liver in fat metabolism when well fed
Definition
increases fatty acid synthesis, turns chylomicrons into fatty acids then TAG which are transported to adipose in VLDL
Term
describe the role of the liver in amino acid metabolism when well fed
Definition
increases amino acid degration sending amino acids to the blood, tissues, or to be deaminated, uses AA in the tCA cycle for fat synthesis, increase protein synthesis
Term
describe the role of the adipose tissue in well fed metabolism
Definition
increases glycolysis to give energy, makes glycerol and uses VLDL FA to make fat, stores FA brought by VLDL
Term
why does adipose have to make glycerol
Definition
because the glycerol brought with the FA it stores, from the VLDL from the liver cannot enter the cell so to store TAG it needs to make its own glycerol to pair with the FA
Term
how does insulin inhibit TAG degredation
Definition
insulin causes phosphorlyzation of hormone sensitive lipase which inactivates it stopping TAG break down
Term
for what reason does muscle change its role in metabolism
Definition
changes in demand for ATP from muscle contraction
Term
what glucose receptors does adipose tissues have
Definition
GLUT 4 insulin sensitive
Term
what glucose receptors does skeletal muscle have
Definition
GLUT 4 insulin sensitive
Term
what role does the skeletal muscle have in carbohydrate metabolism when well fed
Definition
increases glucose transport due to increased blood glucose levels or insulin and does glycolysis with it, or increases glyogen synthesis
Term
what role does skeletal muscle play in amino acid metabolism when well fed
Definition
increases protein synthesis, increases uptake of branched chain AA to do protein synthesis
Term
what is the primary site for amino acid degredation
Definition
skeletal muscle
Term
how does heart muscle store glycogen or lipids
Definition
it doesnt
Term
does the heart need glucose storage? why
Definition
no, it is aerobic and needs oxygen at all times
Term
what does the heart muscle use for energy
Definition
fatty acids, glucose, ketone bodies
Term
for what reason does muscle change its role in metabolism
Definition
changes in demand for ATP from muscle contraction
Term
what glucose receptors does adipose tissues have
Definition
GLUT 4 insulin sensitive
Term
what glucose receptors does skeletal muscle have
Definition
GLUT 4 insulin sensitive
Term
what role does the skeletal muscle have in carbohydrate metabolism
Definition
increases glucose transport due to increased blood glucose levels or insulin and does glycolysis with it, or increases glyogen synthesis
Term
what role does skeletal muscle play in amino acid metabolism when well fed
Definition
increases protein synthesis, increases uptake of branched chain AA to do protein synthesis
Term
what is the primary site for amino acid degredation
Definition
skeletal muscle
Term
how does heart muscle store glycogen or lipids
Definition
it doesnt
Term
does the heart need glucose storage? why
Definition
no, it is aerobic and needs oxygen at all times
Term
what does the heart muscle use for energy
Definition
fatty acids, glucose, ketone bodies
Term
why does the brain need to use only glucose for fuel
Definition
FA cannot get across blood brain barrier
Term
when does the fasting state occur
Definition
approx 4 hrs after meal
Term
what type of reactions occur in the fasting state
Definition
catablic
Term
what is the first thing to happen when fasting that triggers the other fasting processes
Definition
blood glucose, AA, and TAG fall
Term
what does the pancreas do in response to low blood glycose, AA, or TAG
Definition
decreases insulin release, increases glucagon synthesis
Term
when fasting, what are the two main concerns the body has before all other
Definition
maintain blood glucose level for tissues (especially RBC and brain), mobilize FA and ketone
Term
what are the types of stored fuel in the body, how much energy can they provide relative to eachother
Definition
glycogen (provides little energy), protein (provides medium energy), TAG (provides most energy)
Term
how much protein can be lost in fasting before there are fatal complications
Definition
1/3
Term
what is the main function of the liver in fastin
Definition
maintain glucose levels
Term
how is the liver involved in carbohydrate metabolism when fasting
Definition
degrades glycogen into glucose, once glycogen depletes it does gluconeogenesis
Term
how is the liver involved in fat metabolism when fasting
Definition
it takes the products of fatty acid oxidation and uses them for gluconeogenesis. it takes in ketones and does ketoneogenesis
Term
what is the role of adipose in carbohydrate metabolism when fasting
Definition
decreased insulin causes endocytosis of GLUT 4 insulin sensitive receptors, this decreases enterance of glucose and decreases glycolysis
Term
what role does adipose tissue have in fat metabolism in fasting
Definition
degrades TAG for fuel. releases FA for fuel and glycerol to be used in gluconeogenesis in the liver, decreases FA uptake
Term
what role does skeletal muscle have in carbohydrate metabolism when fasting
Definition
decreased insulin causes endocytosis of GLUT 4 insulin sensitive receptors, this decreases enterance of glucose and decreases glycolysis
Term
what role does skeletal muscle have in lipid metabolism when fasting, what changes occur over time
Definition
uses ketone bodies and FA as fuel, at 2 weeks it uses FA almost exclusivly
Term
whty does the skeletal muscle change to only using FA when fasting
Definition
because they brain needs the ketone bodies
Term
what is the role of skeletal muscle in protein metabolism during fasting
Definition
breas down providing protein for gluconeogensis
Term
in the first few days of fasting what does the brain use as food
Definition
glucose only
Term
after prolonged fasting what does the brain use for food, why
Definition
mostly keytone bodies to conserve muscle protein
Term
what is the role of kidney in metabolism
Definition
can make or release glucose, metabolizes glutamein reasing ammonia which picks up H+ put into blood by ketone bodies (ketoacidosis), ammonia pickes up the acid and is excreted in urine
Term
what is the most abundent organic molecule
Definition
carbohydrates
Term
what are the functions of carbohydrates
Definition
calories, energy source via glycogen, membrane compooents that mediate communication, structural components
Term
what types of structural membrane components do carbohydrates make
Definition
bacteria cell wall, exoskeleton of insects, fibrous cellulose of plants
Term
what is the basic structural unit of a carb
Definition
monosaccharide
Term
how are monosacchardies named / classified. give examples
Definition
by number of carbons (triose, tetroses, pentoses, hexoses
Term
what functional groups can a carb have (how does this also change the name of the molecule)
Definition
aldehyde (aldoses), ketone (ketoses)
Term
what are the names of the polymeres of carbs, how many monomoeres do they specify
Definition
disaccharide 2, oligosaccharide 3-10, polysaccharide > 10
Term
what is an isomere
Definition
same formula, different structure
Term
what is an example of an isomere
Definition
glycose vs fructose
Term
when numbering carbons on a carb, what do you begin with
Definition
aldehyde
Term
what type of monosaccharides are usually cyclic
Definition
ones with >5 carbons
Term
what interaction causes cyclic carbs
Definition
aledhyde or keytone reacts with -OH of same sugar
Term
what is a pyarnose
Definition
6 membered ring with 5 C and 1 O
Term
what is a furanos
Definition
5 membered right with 4 C and 1 O
Term
when a carb is cyclic what does this do to the structure
Definition
causes there to be an anomeric C (isomere) that is in alpha or beta form
Term
how is the anomeric carbon on a carb physiologically relivent
Definition
enzymes only react with one of the anomeric conformations
Term
what bond joins monosaccharides
Definition
glycocidic
Term
what are the different types of glycidic bonds
Definition
alpha and beta (depending on isomere of the sugar)
Term
what makes lactose
Definition
glycose and galactose
Term
what makes sucrose
Definition
fructose and glucose
Term
what makes maltose
Definition
many glucose
Term
describe the structure of glycogen
Definition
many glucose alpha linked and branched
Term
where does starch come from
Definition
plants
Term
where does glycogen come from
Definition
animals
Term
where does cellulose come from
Definition
plants
Term
describe the structure of starch
Definition
glucose alpha linked and branched
Term
describe the structure of cellulose
Definition
many glucose beta linked
Term
how are glycocidic bonds named
Definition
according to connected carbons: C1 to beta-galactose = B1-4 glycocidic bond
Term
what are complex carbohydrates
Definition
carbs attached to non-carb structures
Term
gives some examples of complex carbohydrates
Definition
purines and pyrimidines, aromatic rings in steriods, glycoproteins, glycolipids
Term
what is the bond called when a sugar is attached to a non carb with the NH2 group
Definition
N-glycocidic link
Term
what is the bond called when a sugar is attached to a non carb with the -OH group
Definition
O-glycocidic link
Term
explain the process of digestion of carbs
Definition
1. mouth: salivary amalyase breaks a1-4 of starch and glycogen
2. low stomach pH inactivates salivary amalyase
3. SI: pancreatic amalyase, similar to salivary amalyase
4. luminal side of brush border membrane intestinal cells secrete different enzymes
4. monosaccharidestaken up by transporter
Term
what enzymes does the lumenal side of the brush border membrane intestinal mucosa cells release
Definition
sucrase isomaltase complex, maltase, lactase
Term
what does the sucrase portion of the sucrase isomaltase complex do
Definition
digests sucrose into glucose and fructose
Term
what does the isomaltase portion of the sucrase isomaltase complex do
Definition
cleaves maltose into 2 glucose. cleaves a1-6 bonds
Term
what does maltase to
Definition
cleaves maltose and maltotriose a1-4 bonds
Term
what does lactose do
Definition
cleaves lactose
Term
what happens in the large intestines when there is abnormal digestion of carbs
Definition
disaccharides end up in LI causing osmotic pressure leading to diarrhea. bacteria in the LI ferment carbs into CO2, H2, and methane. they also make 1-3 C compounds increasing osmotic imbalance leading to diarrhea
Term
what conditions can cause abnormal digestion of carbs
Definition
inflammatory bowel disease (chron's disease), malnutrition, drugs (chemotherapeutics), dietary intolerances
Term
what is defficient in a lactose intolerance, how do you treat it
Definition
lactase. avoid milk, suppliment with Ca
Term
what mutation causes a lactose intolerance
Definition
none! the people with the intolerance are normal
Term
when someone has a sucrase-isomaltase complex deficiency, what is the result
Definition
sucrose intolerance
Term
how do you treat a sucrose intolerance
Definition
avoid sucrose, take replacement enzymes
Term
how can you diagnose dietary intolerances
Definition
oral tolerance test, takes a H+ breath measurement. H+ is proportional to sugar metabolized
Term
what does glycolysis produce if you have oxygen and mitochondroa
Definition
makes intermediates for other pathways, ATP, pyuvate
Term
what does glycolysis produce if you dont have oxygen or mitochondria
Definition
intermediates for other pathways, ATP, lactate
Term
what are the ways to transport glycose into a cell
Definition
Na independent facilitated diffusion, Na monosaccharide cotransporter
Term
what occurs in sodium independent facilitated diffusion
Definition
high glucose out of the cell and low in makes a gradient glucose 1-14 transporters span mambrane and change conformation when glucose binds transporting it across the membrane
Term
where are glut 1 and 3 transporters located
Definition
in most tissues, especially brain (1) and neurons (3)
Term
what do glue 1 and 3 transporters function in
Definition
basal uptake of gluose
Term
where are glut 2 transporters located
Definition
liver, pancreatic beta cells
Term
what do glut 2 transporters function in, what conditions do they need
Definition
uptake and release, glucose sensors, low affinity, need lots of glucose to work
Term
where are glut 4 transporters located
Definition
skeletal muscle and adipose
Term
what do glut 4 transporters function in, what conditions do they need
Definition
stimulated by glucose uptake and exercise. insulin sensitive. come to surface when insulin is present
Term
how does sodium monosaccharide cotransport work
Definition
uses energy to transport glucose against its gradient by cotransporting it with sodium down sodium's gradient
Term
where does sodium monosaccharide cotransport happen
Definition
epithelial cells of intestine, renal tubules, choroid plexus, sodium dependent glucose transporter
Term
what does sodium monosaccharide cotransport do in epithelial cells
Definition
concentrates sugars
Term
what does sodium monosaccharide cotransport do in renal tubules
Definition
resorbs glucose
Term
wha does sodium monosaccharide cotransport do in the choroid plexus
Definition
allows glucose to cross blood brain barrier into CSF using glut 1
Term
what is the role of sodium monosaccharide cotransport in sodium dependent glucose transporters
Definition
needs tissue specific isoforms
Term
what are the first 5 reactions of glycolysis function in
Definition
energy investment, provides phosphorlyated forms of intermediates
Term
what do the first 5 reactions use
Definition
2 ATP and glucose
Term
what do subsequent generations of glycolysis make
Definition
4 ATP, glucose 2 NADH, pyruvate
Term
in glycolysis what does glucose turn into next, what enzymes help
Definition
glycose-6-phosphate, hexokinase or glucokinase
Term
where is hexokinase active in glycolysis
Definition
most tissues
Term
in glycolysis describe rate and affinity of hexokinase
Definition
low affinity, low Vmax. can be easily saturated
Term
in glycolysis what inhibits hexokinase
Definition
glucose-6-phosphate
Term
in glycolysis where is glucokinase used
Definition
liver, pancreatic B cells
Term
in glycolysis describe rate and affinity of glucokinase
Definition
high affinity, high Vmax
Term
what isglucokinase stimulated by
Definition
insulin
Term
in glycolysis what does glucose-6-phosphate turn into
Definition
fructose 6-phosphate
Term
what enzymes tunrs glucose-6-phoshate into fructose-6-phoshate
Definition
phosphoglucose isomerase
Term
what is the rate limiting step in glycolysis
Definition
fructose-6-phosphate to fructose-1,6-biphosphate
Term
what is the committed step in glycolysis
Definition
fructose-6-phosphate to fructose-1,6-biphosphate
Term
what enzyme catalyzes fructose-6-phosphate to fructose-1,6-biphosphate
Definition
phosphofructokinase 1 (PFK 1)
Term
what inhibits PFK 1, what do these forms of inhibition suggest physiologically
Definition
ATP (you have enough energy), citrate (TCA is backed up)
Term
what stimulates PFK 1, what do these forms of stimulation suggest physiologically
Definition
AMP (you have low energy, ATP was used up), fructose-2,6-Bisphosphate (there is insulin present
Term
what are the irreversible reactions in glycolysis
Definition
phosphoralyzation of glucose, fructose-6-phosphate to fructose 1,6-bisphosphate, phosphoenolpyruvate to pyruvate
Term
where does fructose-2,6-bisphosphate regulates glycolysis
Definition
the liver
Term
what needs to happen for fructose-2,6-bisphosphate to be produced
Definition
insulin needs to be present which causes PFK-2 to be DEphosphorlyated
Term
what needs to happen for fructose-2,6-bisphosphate to not be produced
Definition
glucagon needs to be present causing PFK-2 to be phosphorlyated
Term
what does fructose-2,6-bisphosphate do for regulation of glycolysis
Definition
when insulin is present it is made and it activates PFK-1
Term
what enzyme helps make fructose-2,6-bisphosphate
Definition
PRK-2
Term
in what state is PFK-2 when it is active
Definition
DEphosphorlyated
Term
are PFK-1 and PRK-2 usually active at the same time, why would this be
Definition
yes, because they both help glycolysis go forward. PFK-2 creates a product that helps PFK-1
Term
in glycolysis, what does fructose-1,6-bisphosphate turn into, how?
Definition
the 6 C molecule splits into 2x 3 C molecules: dehydroxyacetone phosphate and glyceraldehyde-3-phosphate
Term
are dehydroxyacetone phosphate and glyceraldehyde-3-phosphate both used in glycolysis? what happens in glycolysis between these molecules? how?
Definition
dehydroxy acetone phosphate is turned into glyceraldehyde-3-phosphate for glycolysis to continue via triose-phosphate-isomerase
Term
what catalyzes the conversion of fructose-1,6-bisphosphate to dehydroxyacetone phosphate and glyceraldehyde-3-phosphate?
Definition
aldolase (not aldolase B!)
Term
in glycolysis, what does glyceraldehyde-3-phosphate turn into? what major changes occur during this step to the molecule? why?
Definition
1,3-BPG. an inorganic phosphate is added for future ATP creation. NAD+ is converted to NADH which is high energy
Term
what enzyme catalyzes the conversion of glyceraldehyde-3-phosphate into 1,3-BPG?
Definition
glyceraldehyde-3-phosphate dehydrogenase
Term
in glycolysis what does 1,3-BPG turn into? what major event takes place assisting the formation of the product?
Definition
the inorganic phosphate is removed from 1.3-BPG and given to ADP making ATP! the product of this is 3-phosphoglycerate
Term
what is substrate level phosphorlyation
Definition
energy for phosphorlyation comes from substrate
Term
what enzyme catalyzes the conversion of 1,3-BPG to 3-phosphoglycerate
Definition
phosphoglycerate kinase
Term
what reactions in glycolysis participate in substrate level phosphorlyation
Definition
1,3-BPG to 3-phosphoglycerate, phosphoenolpyruvate to pyruvate
Term
in glycolysis what does 3-phosphopglycerate turn into? what enzyme helps this?
Definition
2-phosphoglycerate via phosphoglycerate mutase
Term
in glycolysis what does 2-phosphoglycerate turn into? what enzymes helps this?
Definition
phosphoenolpyruvate (PEP), via enolase
Term
what is the final step in glycolysis
Definition
PEP to pyruvate
Term
what catalyzes the final step in glycolysis
Definition
pyruvate kinase
Term
what atom interchange facilitates the conversion of PEP to pyruvate, what is the product of this
Definition
an inorganic phosphate from PEP is removed and given to ADP making ATP! the result is pyruvate
Term
what stimulates pyruvate kinase
Definition
in the liver insulin activates it, fructose-1,6-bisphosphate
Term
what inhibits pyruvate kinase
Definition
in the liver glucagon inactivates it
Term
how is pyruvate kinase really controlled by the PFK-1 reaction (which is the true regulatory reaction)
Definition
pyruvate kinase is controlled by the product of this reaction, fructose-1,6-bisphosphate, so pyruvate kinase is in turn controlled by the same stuff PFK-1 is controlled by because it needs to be working to make fructose-1,6-bisphosphate
Term
in what state is pyruvate kinase turned on
Definition
dephosphorlyated
Term
in what state is pyruvate kinase turned off
Definition
phosphorlyated
Term
what moleule can be turned into 2,3-BPG
Definition
1,3-BPG
Term
what enzyme turns 1,3-BPG into 2,3-BPG
Definition
bisphosphoglycerate
Term
what does 2,3-BPG do
Definition
lowers Hb affinity, increasing O2 drop off in the tissues
Term
how can 2,3-BPG be lowered
Definition
phosphatase can turn it into 3-phosphoglycerate which can be sent back into glycolysis
Term
if there is oxygen and mitochondria, what is pyruvate turned into
Definition
acetyl CoA
Term
if there is no oxygen or mitochondria, what is pyruvate turned into
Definition
lactate
Term
what enzyme helps turn pyruvate into lactate
Definition
lactate dehydrogenase
Term
what does pyruvate turning into lactate produce, what function does this product have
Definition
it turns NADH into NAD+ which allows glycolysis to keep going because it is a needed product
Term
what is the fate of some of the lactate after produced due to an anaerobic enivornment
Definition
it goes to the blood then to the liver where it can be used in gluconeogenesis where its reversabe enzyme (lactate dehydrognase) can turn it back into pyruvate to make glucose
Term
what os oxaloacatate made from
Definition
pyruvate
Term
what can oxaloacetate do
Definition
replenish TCA intermediates, glucoenogenesis
Term
what is the net yield of glycolysis, why
Definition
2 ATP and 2 NADH. a 6 C molecule split into 2x 3 C molecules. this created two pathways that each produced 2ATP and 1NADH. it cost 2 ATP to run glycolysis
Term
what is the net yield of glycolysis done in an anaerobic enivornment
Definition
2 ATP
Term
what changes occur in glycolysis if there are prolonged levels of insulin exposure in the body
Definition
it would increase in transciprion of proteins involved in glycolysis
Term
why would there be an decrease in transcription of proteins revolving around glucagon
Definition
fasting, untreated type 1 diabetes
Term
why would someone have prolonged exposure to insulin
Definition
increased carbohydrate diet, insulin therapy
Term
what happens when someone has a glucokinase mutation
Definition
increases Km or decreases Vmax. this increases blood sugar causing maturity onset diabetes of the young
Term
how does arsenic primairly poison the body
Definition
inhibition of enzymes that use lipoic acid (a coenzyme)
Term
what does arsenic disrupt in glycolysis
Definition
inserts into glyceraldehyde instead of an inorganic phosphate so in the next step, 1,3-BPG to 3-phosphoglycerate, no ATP is made.
Term
what occurs in a pyruvate kinase mutation
Definition
increases Km or decreases Vmax, in RBC pumps that maintain the shape fail because there is no ATP which causes damage to the RBC in vascular system and for them to be removed from circulation causing hemolytic anemia
Term
what is the second most common genetic enzyme deficiency that causes hemolytic anemia
Definition
pyruvate kinase mutation
Term
what is the first most common genetic enzyme deficiency that causes hemolytic anemia
Definition
glucose-6-phoshpate dehydrogenase deficiency
Term
what is different between a glucose-6-phoshpate dehydrogenase deficiency and a pyruvate kinase deficiency.. other than the ovbious different enzyme
Definition
in the glucose-6-phoshpate dehydrogenase deficiency there are Heinz bodies
Term
what are heinz bodies
Definition
percipitated Hb
Term
where is lactate made
Definition
RBC and exercising muscle
Term
in muscles, what does excess lactate cause
Definition
muscle cramping
Term
after lactate is made in RBC and muscle, where does it go
Definition
into the plasma and is then taken up by the liver / tissues or other paths
Term
what happens if there is a lot of lactate in the blood
Definition
lactic acid acidosis (low blood pH)
Term
what happens when there is no oxygen and lactate builds up in a tissue
Definition
cell death / necrosis
Term
where is fructose found in the diet
Definition
sucrose, fruit, table sugar
Term
how is fructose taken into the cell, how does this affect the chemical messengers in metabolism
Definition
by non-insuliin dependent transporters, does not promote insulin secretion
Term
what is the first (common) step in fructose metabolism
Definition
fructose to fructose-1-phosphate using ATP vua fructokinase
Term
where is fructokinase located
Definition
mostly in the liver, kidney, small intestine mucosal cells
Term
what is the first (uncommon) step in fructose metabolism. why is it uncommon
Definition
fructose to fructose-6-phosphate vua hexokinase. because hexokinase has a low affinity so you would need a lot of fructose
Term
what is fructose-1-phosphate turned into, by what
Definition
DHAP and glyceraldehyde by aldolase B
Term
what pathways can aldolase B be part of, why is it special
Definition
it can be part of glycolysis or fructose metabolism, but none of the other aldolases that can take part in glycolysys can do fructose metabolism.
Term
in fructose metabolism, what happens to glyceraldehyde
Definition
it is turned into glycerol. turned into glyceraldehyde-3-P and used for glycolysis or gluconeogenesis
Term
what happens to DHAP in fructose metabolism
Definition
it is used for glycolysis or glyconeogenesis
Term
why is fructose rapidly metabolized
Definition
because it skips the PFK-1 step in its metabolism, it is not regulated like glycolysis is
Term
what turns glucose into sorbitol
Definition
aldosa reductase
Term
what turns sorbitol into fructose
Definition
sorbitol dehydrogenase
Term
where is aldose reductase located
Definition
lens, retina, schwann cells of peripherial nerves, liver, kidney, cells of ovaries, seminal vesicles
Term
where is sorbitol located
Definition
liver, kidney, ovaries, seminal vesicles
Term
what happens in an sorbitol dehydrogenase deficiency
Definition
glucose turns into sorbitol and it builds up making osmotic water uptake causing diabetes symptoms: cataracts, retinopathy, neuropathy
Term
what can cause glucose to turn into sorbitol
Definition
some tissues require the product of the next step, fructose. if there is a lot of glucos ein the blood this will just happen
Term
what is the name of the disease with a fructosekinase deficiency
Definition
essential fructoseuira / HFI
Term
what does a fructose kinase deficiency cause
Definition
elevated sugar levels in urine, benign
Term
why is cataracts not a symptom of fructose kinase deficiency
Definition
because fructose is not a substrate for aldolase reactions
Term
what does aldolase B deficiency cause
Definition
fructose intolerance, hepatomeaguly, jaundice, hypoglycemia, renal dysfunction
Term
how is aldolase b deficiency treated
Definition
avoid fructose, sucrose, and sorbitol
Term
what are the steps in an aldolase b deficiency causing hyperuricema
Definition
fructose enters the cell and is phosphorlyated trapping it in, it cannot be metabolized so it builds up, cellular phosphate is tied up trying to phosphorlyate fructose decreasing ATP levels, AMP builds up causing AMP degeneration leading to hyperuricema
Term
what is the first step in galactose metabolism
Definition
galactose to galactose-1-phosohate using galactose kinase and ATP.
Term
what does galactose-1-phosphate turn into, using what enzyme
Definition
galactose-1-phoshpate uridyltransverase helps it chane to UDP galactose and glucose-1-phosphate (using a UDP glucose made by the cell and exchanging UDP for P)
Term
what are the symptoms of a galactokinase deficiency
Definition
cataracts early
Term
how does a galactokinase deficiency cause cataracts
Definition
galactose is a substrate for aldose reductase so when it builds up it reacts with that as a catalyst to make galactiol which is trapped in the cell and causes an osmotic gradient
Term
what disease does a galactose-1-phosphate uritotransferase deficiency cause
Definition
classic galactosemia
Term
what are the symptoms of classic galactosemia
Definition
early cataracts, liver and kidney damage, nerve damage (retardation)
Term
what chemical process causes the symptom of cataracts in classic galactosemia
Definition
increased galactose-1-phosphate inhibits galactokinase which increases galactose causing cataracts
Term
what chemical process causes the symptoms of classic galactosemia
Definition
increased galactose-1-phosphate ties up the use of the cell phosphate causing decreased ATP
Term
how is classic galactosemia treated
Definition
avoid galactose
Term
what does TCA stand for
Definition
tricarboxcylic acid cycle
Term
what are other ways to say TCA cycle
Definition
crebs cycle, CAC
Term
overall what does the TCA cycle do
Definition
metabolizes carbs, AA, FA into CO2 which is exhaled. ATP production.
Term
where does the TCA cycle occur
Definition
in mitochondria near the ETC
Term
what does the ETC do, in general
Definition
couples oxidation of reduced coenzymes made in TCA to production of ATP
Term
what is the TCA cycle dependent on, why
Definition
oxygen, it is aerobic. because O2 is the final e- acceprot in the ETC
Term
what origional ingredients are lost in the TCA cycle, explain
Definition
none, oxaloacetate is the rectant and the final product of the ccle
Term
what is the reaction that connects glycolysis to the TCA cycle
Definition
oxidative decarboxylation of purivate, pyruvate to acetyl CoA
Term
what are the reactantS and productS of oxidative decarbodylation of pyruvate
Definition
pyruvate + CoA + NAD+ --> NADH + CO2 + acetyl CoA
Term
what enzyme catalyzes oxidative decarboxylation of pyruvate
Definition
pyruvate dehydrogenase complex
Term
is oxidative decarboxylation of pyruvate a comitted step, what does that mean
Definition
yes, only goes in one direaction
Term
what activates pyruvate dehydrogenase
Definition
pyruvate, NAD+, ADP, Ca in muscle, CoA
Term
what deactivates pyruvate dehydrogenase
Definition
acetyl CoA, NADH, ATP
Term
before oxidative decarboxylation of pyruvate, but after glycolysis what needs to happen
Definition
pyruvate needs to be transported into the mitochondria via sepcific transporters
Term
what are the coenzymes included in the pyruvate dehydrogenase complex
Definition
thiamine pyrophosphate (TPP), lipoid acid, CoA, FAD, NAD+
Term
where does lipoic acid come from
Definition
made in the body
Term
where does CoA come from
Definition
pantothenic acid
Term
where does FAD come from
Definition
riboflavin
Term
where does NAD+ come from
Definition
niacin
Term
how many ATP are made total per glucose in the TCA cycle
Definition
12
Term
what is the break down of true products that adds up to 12 ATP total made in TCA cycle
Definition
3 NADH = 9 ATP,
1 FADH2 = 2 ATP,
1 GTP = 1 ATP
Term
after the TCA cycle, how many ATP have been made total
Definition
38
Term
explain how there are 38 total ATP after TCA per molecule of glucose
Definition
glycolysis: 8
oxydative decarboxylation of pyruvate: 2 NADH = 6 ATP
TCA: 24 ATP
Term
explain how glycolysis produces 8 ATP per molecule of glucose
Definition
2 ATP
2 NADH = 6 ATP
Term
in the TAC what does oxaloacetate turn into, what does it need to do this
Definition
citrate. it needs acetyl CoA and citrate synthase
Term
what regulates citrate synthase
Definition
substrate/product regulation
Term
what are the irreversible reaction enzymes of TCA
Definition
citrate synthase, isocitrate dehydrogenase, alpha-ketogluterate dehydrogenase complex
Term
what is the rate limiting step of TAC
Definition
isocitrate to alpha-ketogluterate via isocitrate dehydrogenase
Term
in the TAC what does citrate turn into
Definition
it can go inhibit PFK-1, it can do fatty acid synthesis, or turn into isocitrate
Term
what catalyzes citrate into isocitrate
Definition
acontiase
Term
what type of reaction is citrate to isocitrateq
Definition
isomerization
Term
what does isocitrate turn into in the TAC, what does it need to do this, what are all the products
Definition
isocitrate + NAD --> NADH + CO2 + alpha-ketogluterate
Term
what type of reaction is isocitrate to alpha-ketogluterate
Definition
oxidation and decarboxylation
Term
what inhibits isocitrate dehydrogenase
Definition
NADH, ATP
Term
what stimulates isocitrate dehydrogenase
Definition
Ca in muscle, ADP
Term
what enzymes of the TCA are involved in reactions that make NADH
Definition
isocitrate DH, alpha-ketogluterate DH, malate DH
Term
what enzymes of the TCA are involved in reactions that make CO2
Definition
isocitrate DH, alpha-ketogluterate DH
Term
what enzymes of the TCA are involved in reactions that make GTP
Definition
succinatethiokinase
Term
what enzymes of the TCA are involved in reactions that make FADH2
Definition
succinate DH
Term
what does alpha-ketogluterate turn into in TCA, what are the other substrates and products
Definition
CoA + NAD + alpha-ketogluterate --> NADH + CO2 + succinyl CoA
Term
what enzyme turns alpha-ketogluterate into succinyl CoA
Definition
alpha-ketogluterate DH
Term
what inhibits alpha-ketogluterate DH
Definition
NADH, Succinyl CoA
Term
what stimulates alpha-ketogluterate DH
Definition
Ca in muscle
Term
what type of reaction does alpha-ketogluterate DH catalyze
Definition
oxidative decarboxylation
Term
what is alpha-ketogluterate DH simillar to
Definition
pyruvate kinase DH complex
Term
in the TCA what does succinyl-CoA turn into, what are they other products and reactants
Definition
succinyl CoA + GDP --> GTP + succinate
Term
what enzyme catalyzes succinyl Coa to succinate
Definition
succinate thiokinase
Term
what type of reaction does succinate thiokinase catalyze
Definition
substrate level phosphorlyation
Term
what does GTP from the TCA turn into
Definition
ATP
Term
in the TCA what does succinate turn into, what are the other reactants and products
Definition
succinate + FAD --> fumurate + FADH2
Term
what catalyzes succinate to fumerate
Definition
succinate DH
Term
where is succinate DH located
Definition
mitochondrial membrane
Term
what does succinate DH do
Definition
succinate to fumerase. complex II of ETC
Term
what does fumurate turn into in the TCA, what are the other products and reactants
Definition
malate + water
Term
what is malate turned into in the TCA, what are the other products and reactants
Definition
malate + NAD --> NADH and oxaloacetate
Term
what does arsenic poisoning do in the TCA cycle
Definition
removes lipolic acid inhibiting PDH and alpha-ketogluterate DH
Term
how can blocking the ETC block the TCA
Definition
decreasing O2 for example, causes build up of products and inhibits TCA
Term
what does a niacin or thiamine deficiency cause
Definition
decreases the activity of PDH and alpha-ketogluterate DH, this leads to CNS problems because the brain needs glucose to survive
Term
what is another name for wernickle korsakoff syndrome
Definition
encephalopathy psycosis syndrome
Term
what occurs in wernickle korsakoff syndrome
Definition
decreaded thiamine causes decreased activity of PDH and alpha-ketogluterate DH
Term
who commonly has wernickle korsakoff syndrome
Definition
chronic alcoholics
Term
what are the names of diseases with a PDH deficiency
Definition
leign syndrome, subacute necrotizing encephalomelopathy
Term
what occurs in a PDH deficiency
Definition
pyruvate cannot go into the TCA cycle so it goes to making lactic acid, leads do chronic lactic acid acidosis
Term
what are the symptoms of PDh deficiency
Definition
neuro degeneration, muscle spasticity, early death
Term
What is the general overall story of ETC
Definition
Glucose is oxidized to CO2 and water coupled to the transfer of electrons of coenzymes FAD and NAD to yield energy as NADH and FADH2. They donate electrons to electrons carriers which makes energy for a pump that creates a gradient that is coupled to ATP production
Term
What is an alternative route for the energy made from ETC, other than ATP production
Definition
Ancillary reactions (Ca transport in mitochondria making heat)
Term
Where does ETC occur
Definition
Inner mito membrane
Term
At what point does the ETC turn off
Definition
It only turns off when oxygen isn't present, it is Always running
Term
What is the outer membrane permeable to
Definition
Most ions and small molecules
Term
What is the inner membrane permeable to
Definition
Few ions or molecule.s need carriers
Term
What is the inner mitochondrial membrane made of
Definition
Lots of proteins (50% are ETC proteins), very convoluted forming cristae to increase surface area
Term
What is the mitochondrial matrix made of
Definition
50% protein, gel like, enzymes for oxidating pyruvate amino acids, fatty acids beta-oxidation, and TCA. NAD, FAD, ADP, Pi. Mitochondrial DNA and replication / expression tools.
Term
What drives transfer of electrons in ETC
Definition
NADH is a good electron donor and oxygen a good acceptor
Term
What happens to the strength of the donors as you go through the etc
Definition
Each donor is weaker and acceptors are stronger
Term
What is the common intermediate between oxidation and oxidative phosphorylation
Definition
Protein gradient
Term
Where does the NADH and H come form for etc
Definition
Dehydrogenase reactions
Term
Where does NADH enter into the etc chain
Definition
Complex 1
Term
What is another name for complex 1
Definition
NADH dehydrogenase
Term
What occurs in NADH dehydrogenase
Definition
FMN accepts 2H / 2e- making FMNH2 assisted by the Fe/S center
Term
Where does FADH2 enter the etc
Definition
It sends 2H / 2e to cytochrome c
Term
What is coenzyme q
Definition
A non membrane bound lipid electron carrier
Term
Where does coenzyme q take electrons to
Definition
Complex 3: cytochrome BC1
Term
What picks up electrons from cytochrome bc1
Definition
Cytochrome c
Term
Where does cytochrome c take electrons do
Definition
Cytochrome c oxidase, complex 4
Term
What does cytochrome c oxidase do
Definition
Uses Fe and Cu to help use 2H / 2e to reduce oxygen to water
Term
What complexes are not membrane bound in etc
Definition
Cytochrome c and coenzyme q, the electrons carris
Term
What complexes pump protons out in their electron transport exchange
Definition
Complex 1, 3, 4
Term
In regard to the gradient, what is the outside of the mitochondrial membrane like
Definition
Positive with low ph
Term
In regard to the gradient, what is the inside of the mitochondrial membrane like
Definition
Negative, higher ph
Term
Describe the composition and role of a cytochrome
Definition
Has heme, involved in electron transport, reversible oxidized or reduced Fe
Term
Where is the Fo subunit of complex 5 located
Definition
Membrane spaning
Term
Explain the role of the F1 subunit of complex 5
Definition
Rotation of the unit is driven by the gradient, this allows ADP and P to make ATP
Term
What is another name for complex 5
Definition
ATP synthase
Term
In general, what do etc inhibitors do
Definition
Prevent flow of electrons so NADH builds up leading to TCA inhibition, this causes anaerobic glycolysis, increasing lactic acid and decreasing oxygen consumption, aerobic tissues are most effected
Term
What does Amytal do, what is it classified as
Definition
Barbiturate that stops complex 1 of etc
Term
What does rotenone do
Definition
Stops complex 1 of etc
Term
Where is rotenone found
Definition
Insecticide,pesticide, piscicide
Term
What does antimycin do
Definition
Stops complex 3 of etc
Term
What is antimycin found in
Definition
Pisicide
Term
What does positide do
Definition
Kill fish
Term
What does cyanide do
Definition
Irreversibly binds complex 4 in etc, binds iron tight in heme
Term
Why might someone be exposed to cyanide
Definition
House if re, industrial fire, burning polyurethane
Term
what does CN- bind to in ETC
Definition
Fe3+ in heme of complex 4
Term
what does CO do in ETC
Definition
inhibits complex 4 reversibly
Term
what does sodium azide bind to in ETC
Definition
Fe3+ in cytochromes of complex 4
Term
where is sodium azide found
Definition
propellent in airbags, explosives, lab as anti microbial preservitive in sera or other solutions
Term
what does oligomycin do
Definition
binds to complex 5 in ETC closing proton channel leading back to matrix, stops ATP synthesis so also ETC
Term
where is oligomycin found
Definition
tool to study electron transport in lab
Term
where are coupling proteinsfound
Definition
inner mitochondrial membrane
Term
what do coupling proteins do
Definition
allow protons to flow back into matrix without going through complex 5, does not stop ETC but does not make ATP, energy is released as heat
Term
what are examples of coupling proteins
Definition
UPC 1 (thermogenin), synthetic uncouplers, salicylic acid
Term
where is UPC 1 found
Definition
brown adipose
Term
what are synthetic uncouplers
Definition
non-proteins that increase permability of inner mitochondrial membrane to protons which uncouple ETC from ATP production
Term
what is an example of a synthetic uncoupler, what does it cause
Definition
2,4-dinitropherol: weight loss drug, overdose causes fatal hyperthermia
Term
what does salicylic acid do
Definition
uncouples ETC from ATP production, overdose leads to fever and sweating
Term
where is salicylic acid found
Definition
asprin
Term
what is a reactive O2 species formed by
Definition
oxygen improperly turning into water that the end of the ETC
Term
what are the reactive O2 species
Definition
superodixe (O2-), H2O2, hydroxyl radicals (OH)
Term
what do reactive O2 species do
Definition
damage proteins, lipids, DNA, RNA in mitochondria
Term
other than the fact that they damage sruff, why are reactive O2 species a problem
Definition
they mess up the ETC which increases the amount of reactive O2 species making a bad circle of life
Term
how does the body normally combat reactive O2 species
Definition
natural enzymes
Term
what are the natural enzymes the body uses to combat reactive O2 species
Definition
lipid soluble vitamins in membrane (antioxident vitamins, vitamin E), water soluble vitamins in cytosol (vitamin C), superoxide dismutase, catalyase, gltathione peroxidase
Term
what is a reprefusion injury
Definition
decreased O2 > decreased ATP and NADH prodiction. then O2 is suddenly introducd. ETC activity is too much > reactive oxygen species produced
Term
where do the proteins from oxidative phosphorlyation come from
Definition
13/120 are on mitochondrial DNA, the rest are transported into the mitochondria from the nucleus
Term
why does mitochondrial DNA have a higher mutation rate
Definition
reactive oxygen species generation
Term
what do mutations in mitochondrial DNA cause
Definition
oxidative phosphorlyation defects which hurts aerobic tissues causing neuropathies and myopthies
Term
what are examples of mitochondrial DNA mutations
Definition
LHON, MERRF, mitochondrial encephalomyopathy, lactic acidosis, stroke like episodes, leigh syndrome
Term
what is the role of the mitochondria in apoptosis
Definition
may be initiated through intrinsic (mitochondria mediated) path by outer pores of the outer mitochondrial membrane allowing cytochrome C into the cytosol, cytochrome c activates proapoptotic factors to activate proteolytic enzymes (capsases). capsases cleave key proteins leading to morphologicl and biochemical changes of apoptosis
Term
what happens in Fe deficient anemia
Definition
Fe is in the ETC so a defect would lead to faulty ETC and tiredness
Term
where does gluconeogensis occur
Definition
the liver, unless there has been prolonged fasting then the kidney helps
Term
how long can glycogen storage in the liver sustain you
Definition
10-18 hrs
Term
once the liver glycogen storage is depeleted, what kicks in to keep you going
Definition
gluconeogenesis
Term
what is the challenge for the body in completing gluconeogenesis
Definition
need to reverse the three irreversible steps in glycolysis
Term
what are the substrates for gluconeogenesis
Definition
glycerol, lactate, amino acids
Term
how is glycerol involved in gluconeogenesis
Definition
adipocytes release FA by hydrolyzing TAG which also releases glycerol. it is converted to DHAP which can go into gluconeogenesis skipping the pyruvate challenge reaction
Term
why can we just keep using glycerol / gluconeogenesis for energy
Definition
there itsnt enough to give significant energy
Term
where is lactate produced
Definition
RBC and exercising skeletal muscle
Term
what can convert lactate to pyruvate
Definition
lactate dehydrogenase
Term
explain the cori cycle
Definition
lactate made in muscle travels to the liver. gluconeogenesis turns into into glucose, glucose travels to the muscle and is turned into lactate. rinse and repeat
Term
where are amino acids derived from
Definition
hydrolysis of proteins
Term
what is the major amino acid that energy comes from
Definition
alanine
Term
what needs to happen to amino acids before they can be used for energy
Definition
amino must be removed
Term
how many amino acids can be used for energy
Definition
18/20
Term
how are amino acids used for energy
Definition
they become TCA cycle intermediates which can yeild oxaloacetate which can turn into PEP which can be used in gluconeogenesis
Term
how is acetyl CoA used in glucoenogenesis
Definition
it isnt, you cannot convert acetyl CoA into pyruvate, PDH is irreversible
Term
how can actyl CoA provide energy if it canot go into gluconeogenesis
Definition
fatty acid oxidation gives the liver energy to complete gluconeogenesis
Term
what is the first step of gluconeogenesis, what catalyzes it
Definition
pyruvate to oxaloacetate via pyruvate carboxylase and biotin coenzyme
Term
where does the first step of gluconeogenesis take place
Definition
mitochondria
Term
where is pyruvate carboxylase located
Definition
in cells that dont do gluconeogenesis well (muscle) and need to replace TCA intermediates instead
Term
once produced via gluconeogenesis, what is the fate of oxaloacetate
Definition
TCA intermediate or further gluconeogenesis
Term
what does biotin do
Definition
bind CO2 in pyruvate carboxylase
Term
what does pyruvate carboxykinase need to work
Definition
biotin, pyruvate, ATP
Term
what is thee malate shuttle
Definition
oxaloacetate is converted to malate and back to OAA to get through the mitochondrial membrane in gluconeogenesis
Term
what does OAA turn into if going through gluconeogenesis, what enzyme does it
Definition
malate via mitochondrial malate dehydrogenase
Term
after going through the membrane what does malate turn into in gluconeogenesis, using what enzyme?
Definition
OAA via cytosolic malate dehydrogenase
Term
after getting through the mitochondrial membrane, what does OAA turn into, what is needed for this reaction to occur
Definition
OAA + GTP -> PEP
Term
what enzyme turns OAA into PEP
Definition
PEP carboxykinase
Term
in glycolysis PEP is turned into pyruvate, why does this not just happen after we reverse it in gluconeogenesis
Definition
because the enzyme that converts PEP to pyruvate, pyruvate kinase, is inhibited by glycogen
Term
what stimulates pyruvate carboxykinase
Definition
acetyl CoA
Term
what enzyme converts fructose-1,6-bisphosphate into fructose-6-phosphate
Definition
fructose-1,6-bisphosphatase
Term
what activates fructose-1,6-bisphosphatase, what does this indicate physiologically
Definition
ATP, the liver needs energy
Term
what inhibits fructose-1,6-bisphosphatase
Definition
AMP, fructose-2,6-bisphosphate
Term
explain how fructose-2,6-bisphosphate inhibits fructose-1,6-bisphosphatase
Definition
fructose-2,6-bisphosphate gets low glycolysis will shut off and gluconeogenesis will be able to turn on
Term
how does glycogen affect fructose-1,6-bisphosphatase
Definition
it inhibits PFK-2 which decreases fructose-2,6-bisphosphate and increases glucoenogenesis and decreases glycolysis
Term
what turns glucose-6-phosphate into glucose
Definition
glucose-6-phosphatase
Term
what is used in glyconeolysis to yield free glucose
Definition
glucose-6-phosphatase
Term
once productd via gluconeogenesis, where does glucose go
Definition
out of the liver into the blood to supply tissues
Term
what is the cause of von gierke disease
Definition
glucose-6-phosphatase deficience
Term
how does substrate avability regulate gluconeogenesis: muscle
Definition
muscle breaks down into amino acid and its sent to the liver and gluconeogenesis is stimulated by aa.
Term
how does substrate avability regulate gluconeogenesis: fatty acids
Definition
fatty acid oxidation yields ATP and NADH which go to the liver. this stimulates gluconeogenesis
Term
how do the reversible reactions regulate gluconeogenesis
Definition
direction of the reactions depend on substrate vs product regulation
Term
how does acetyl CoA regulate gluconeogenesis
Definition
it allosterically activates pyruvate carboxykinase. if it builds up there isnt enough OAA for it to combine with to make citrate so it activates gluconeogenesis. it inhibits PDH so pyruvate is used for gluconeogenesis so more acetyl CoA isnt made.
Term
how does AMP regulate gluconeogenesis
Definition
allosterically inhibits fructose-1,6-bisphosphate, it activates PRK 1 and makes sure enzymes are muturally exclusive
Term
why is glycogen used in metabolism
Definition
dietary glucose is unreliable, gluconeogenesis is slow so their is a gap it fills when glucose isnt taken in
Term
what parts of the body release sugar
Definition
liver and kidney
Term
why isnt sugar released from the muscle
Definition
it is degraded when ecercising
Term
where is glycogen mainly stored
Definition
skeletal muscle and liver
Term
where is glycogen stored
Definition
skeletal muscle, liver, kidney
Term
what is the only organ that does not use glycogen for itself
Definition
liver
Term
how is glycogen involved in weight gain
Definition
it holds water which increases its weight
Term
describe the structure of glycogen
Definition
branched chain of a-D-glucose with a1-4 and a1-6 bonds that make large granules
Term
where are the enzymes to make or break glycogen located
Definition
associated with the glycogen granules
Term
give a general explination of how glycogen is made
Definition
glucose-1-p + UDP -> UDP glucose, UDP glucose adds onto glycogenin one at a time, every 8 residues there is a branch made
Term
what catalizes glucose-1-phosphate + UDP -> UDP glucose
Definition
UDP glucose phosphorlyase
Term
what catalizes the first 4 residues being put on glycogenin protein
Definition
glycogenin protein
Term
what catalizes more than 4 residies being added to glycogenin protein
Definition
glycogen synthase
Term
what type of bonds does glycogen synthase make
Definition
a1-4
Term
why does glycogen have branches
Definition
to give more ends for synthesis that glucose can be liberated from
Term
how is a glycogen branch made
Definition
glycogen synthase puts on more than 8 branches, 6 are cleaved off and moved down the molecule by branching enzyme
Term
what type of bonds do branching enzyme make
Definition
a1-6
Term
what is another name for branching enzyme
Definition
4-6 transferase
Term
what does glycogen phosphorlyase do
Definition
cleave a1-4 bonds of glycogen yielding glucose 1-phosphate
Term
what is the rate limiting step in glycogen degredation
Definition
glycogen phosphorlyase
Term
why and where does glycogen phosphorlyase stop cleaving (other than hormones and such)
Definition
it reaches steric hinderance near a branch approx 4 residues from it
Term
how are branches removed from glycogen
Definition
debranching enzyme uses 4/4 transferase and 1/6 glucosidase activity
Term
what does glycogen phosphrlyase need to work
Definition
PLP coenzyme
Term
what is PLP derived from
Definition
vitamin b6
Term
what is the 4/4 transferase activity
Definition
debranching enzyme removes 3 of the 4 glucose and attaches them to another branch making a longer chain so glycogen phosphorlyase can act on it
Term
what is the 1/6 glucosidase activity
Definition
debranching enzyme cleaves the branch point of glucogen, yielding free glucose
Term
what turns glucose-1-phosphate into glucose-6-phosphate
Definition
phosphoglucomutase
Term
what turns glucose-6-phosphate into glucose
Definition
glucose-6-phosphatase
Term
what is an alternative way for glycogen to be broken down
Definition
lysosomal alpha glucosidase in the lysosome
Term
explain how, after degrading glycogen, it can be used for energy
Definition
the product of the degredation is glucose-1-phosphate, it can be converted to glucose-6-phosphate and into glucose
Term
what regulates glycogen metabolis, how
Definition
glycogen synthase and phosphorlyase regulators, they have tissue specific isoenzymes
Term
what activates glycogen synthase in the liver
Definition
insulin, glucose-6-phosphate
Term
what inhibits glycogen synthase in the liver
Definition
glucagon, epinepherine
Term
what activates glycogen synthase in the muscle
Definition
insulin
Term
what inhibits glycogen synthase in the muscle
Definition
epinepherine
Term
what activates glycogen phosphorlyase in the liver
Definition
glucagon, epinepherine
Term
what inhibits glycogen phosphorlyase in the liver
Definition
insulin
Term
what activates glycogen phosphorlyase in the muscle
Definition
epinepherine, AMP, CA2+
Term
what inhibits glycogen phosphorlyase in the muscle
Definition
insulin
Term
what causes von gierke's disease
Definition
glucose-6-phosphate deficiency
Term
what does von greike's cause
Definition
severe fastin hypoglycemia, lactic acidosis, hepatomeagly, hyperlipidemia, hyperuricemia, short stature due to growth retardation
Term
what does sever fasting hypoglycemia cause in von gierke's disease
Definition
cannot release glucose from liver from gluconeogenesis or glycogenolysis
Term
what does lactic acidoses cause in von gierke's disease
Definition
glucose-6-phosphate builds up an stops at gluconeogenesis, PDH is inhibited, lactate production is favored, lactate from RBC does not go to gluconeogenesis
Term
what does hepatomeagly cause in von gierke's disease
Definition
glycoen metabolites accumulate in liver and FA synthesis is favored, the liver swells because glycogen likes water
Term
what does hyperlipidemia cause in von gierke's disease
Definition
increased fa synthesis in liver due to deraged glucose in the liver
Term
what does hyperuricemia cause in von gierke's disease
Definition
glucose-6-phosphate build up tieing up cellular phosphate leading to turn over of nucleotides
Term
what causes pompe disease
Definition
lysosomal a1-4 glucosidase deficiency, hurts lysosomal glycogen degredation
Term
what are the symptoms of pompe disease
Definition
like other lysosomal storage disease, accumulation of the compound that cannot be broken down
Term
what causes Cori disease
Definition
debranching enzyme deficiency
Term
what are the symptoms of cori disease
Definition
mild hypoglycemia, liver enlargement, short outer branches of glycogen
Term
why is there mild hypoglycemia in cori disease
Definition
glucose is only released from glycogen until a branch is reached
Term
why is there liver enlargement in cori disease
Definition
accumulation of glycogen remains
Term
what is deficient in anderson disease
Definition
branching enyme
Term
what are the symptoms of andersen disease
Definition
infantile hypotonia, cirrhosis, early death
Term
what is infantile hypotonia
Definition
few branches in glycogen so few ends release glycogen for muscle contraction
Term
what is cirrhosis
Definition
linear glycogen is much less soluble and percipitates, damaging liver cells
Term
why is there early death in andersen disease
Definition
liver and heart are severly affected by percipitated glycogen
Term
what is deficnent in mcCardle disease
Definition
muscle glycogen phosphorlyase
Term
what are the symptoms of McCardle disease
Definition
muscle cramps, cannot release glycogen for muscle contraction, myoglobinuria
Term
what is myoglobinuria
Definition
destruction of some some muscle cells due to exercise induced lack of ATP
Term
what is wrong in Hers disease
Definition
liver gluycogen phosphorlyase deficneicy
Term
what are the symptoms of Hers disease
Definition
mild fasting mypoglycemia, hepatomeagly
Term
what occurs in mild fasting hypoglycemia
Definition
no glucose from glycogen but gluconeogenesis still is function
Term
why does hepatomeagly occur in glycogen storage diseases
Definition
excess build up of glycogen in the liver
Term
describe the solubility of lipids
Definition
hydrophobic, non-polar, water insoluble
Term
what does the solubility of lipids cause the molecules to do
Definition
compartmentalize
Term
how can you dissolve lipids
Definition
non-polar solvents
Term
what are the major functions of lipids
Definition
provide hydrophobic barriers for cell membranes and subcellular compartments, source of energy
Term
what are the minor functions of lipids
Definition
coenzyme or regulatory, regulating homeostasis
Term
what lipids have coenzyme functions
Definition
fat soluble vitamins
Term
what lipids have functions in regulation of homeostasis
Definition
prostaglandins
Term
what has increased intake in saturated FA and cholesterol been shown to cause risk of, what form of fat does not
Definition
dementia, fish
Term
what is the optimal pH for acid lipase
Definition
4-6
Term
what are the enzymes in the stomach that digest lipids
Definition
acid lipase, lingual lipase, gastric lipase
Term
what is an example of something that acid lipase digests
Definition
milk fat
Term
what enzyme is important in neonates for milk digestion
Definition
acid lipase
Term
what does acid lipase target
Definition
short and medium chain FA (<12 C)
Term
where is lingual lipase secreted
Definition
glands at back of tounge
Term
where is gastric lipase secreted
Definition
gastric mucosa
Term
in general what processes emulsify dietary lipids
Definition
complimentary actions: mechanical agitation and secretion of bile salts
Term
what causes mechanical digestion, what does it accomplish
Definition
peristalsis increases surface area of lipid droplets
Term
what do bile salts do
Definition
make smaller particles, detergent stablizes particles so they dont stick back together
Term
where are bile salts made
Definition
liver
Term
where are bile salts stored
Definition
gallbladder
Term
where are bile salts secreted
Definition
small intestines
Term
what do proteolytic enzymes in the small intestines digest
Definition
TAG, cholesterol esters, phospholipids
Term
what digests TAGs in the small intestine
Definition
pancreatic lipase
Term
what does pancreatic lipase cleave TAGs into
Definition
2-monoacylglycerol and FA
Term
what percent of the pancreatic secretion is pancreatic lipase
Definition
2-3%
Term
what does pancreatic lipase need for it to work
Definition
colipase
Term
what does colipase do
Definition
binds pancreatic lipase at a 1:1 ratio moving it to aqueous barrer where inhibitor bile acids are present so enzymes can get to the TAG
Term
ih what form is most dietary cholesterol
Definition
free
Term
what digests cholesterol esters in the small intestines
Definition
pancreatic cholesterol esterase
Term
what does pancreatic cholesterol esterase turn cholesterol esters into
Definition
cholesterol and FA
Term
what activates pancreatic cholesterol esterase
Definition
bile salts
Term
in general how are phosphilipids digested
Definition
aequential removal of FA
Term
what is the process of phospholipid digestion
Definition
1. phospholipase A2 removes FA from position 2 makes lysophorpholipid and FA
2. lisophospholipase removes FA from position one making glycerophosphoryl and FA
3. glycerylphosphorly base is absorbed, digested, or excreted
Term
what conteols pancreatic enzymes
Definition
CCK and secretin
Term
what is CCK secreted from
Definition
mucosal cells of lower duodenum and jejunum
Term
what is CCK released in response to
Definition
lipids, partially digested proteins
Term
what does CCK cause
Definition
contraction of gall bladder releasing bile salts, phospholipids, free cholesterol. exocrine cells of pancreas to secrete hydrolytic enzymes, decreases gastric motility, reducing release of gastric contents into the small intestines
Term
what type of hormone is secretin
Definition
peptide
Term
what makes secretin
Definition
intestinal cells
Term
what does secretin respond to
Definition
low pH of chime entering intestine
Term
what does secretin cause
Definition
bicarbonate release from liver and pancreas, gives appropirate pH for enzyme function
Term
after being digested what happens to the lipid particles
Definition
they form into micelles along with soluble vitamins and bile salts, micelles go to brush border of the membrane of enterocytes and are absorbed
Term
what does lipid digestion in the small intestines generate in the end
Definition
Fa, cholesterol, 2-monoacylglycerol
Term
how do long chain fatty acids get absorbed into brush border
Definition
broken down and put into micelles
Term
how do short and medium chain fatty acids get absorbed into brush border
Definition
they can go right through
Term
once in the enterocytes, what happens to long chain FA
Definition
converted to acyl-Coa at the ER
Term
once in the enterocytes, what happens to 2-monoacylglycerol, what helps
Definition
TAG synthase sequentially adds FA using acyltransferase activities
Term
once in the enterocytes, what happens to lysophospholipids
Definition
reacylated by acyltransferases to form phospholipids
Term
once in the enterocytes, what happens to cholesterol
Definition
esterified
Term
once in the enterocytes, what happens to short and medium chain FA
Definition
not activated, released into portal circulation and carried by serum albumin
Term
what needs to happen to TAG and cholesterol esters before the can leave the enterocyte
Definition
need to be packaged into chylomicrons
Term
what is a chylomicron made of
Definition
TAG and cholesterol esters with a layer of phospholipids, cholesterol, and Apo B48 around the outside
Term
where are chylomicrons made
Definition
ER of enterocytes
Term
once made, what happens to the chylomicron
Definition
exocytosed into the lacteal making the lumph chyle
Term
what is a lacteal
Definition
lymph capillary in the SI villi
Term
what happens when the chylomicron makes chylo
Definition
it is passed into the lymphatic system to thoracic duct to left subclavian then blood
Term
what happens to a chylomicron once it reaches a tissue
Definition
lipoprotein lipase degrades TAG into FA and glycerol
Term
where is lipoprotein lipase secreted
Definition
mostly muscle and adipose but also heart, lung, kidney, liver
Term
what does lipoprotein lipase associate with
Definition
lumen endothelial cells of capillary bed
Term
what happens for FA in circulation
Definition
they are usually taken up immediatly by adjacent muscle or adipose if they dont, they will circulate on albumin until they are
Term
what happens to glycerol after being released into blood
Definition
it is taken up by liver and used to make glycerol-3-phosphate for glycolysis or gluconeogenesis
Term
what remains after the contents of a chylomicron are used by the tissues
Definition
phospholipids, cholesterol esters, apolipoproteins, fat soluble vitamins, TAG
Term
what happens to chylomicron reamins
Definition
interacti with liver cells and are endocytosed
Term
what happens to nitrogenous bases and phospholipids associated with FA transport to tissues
Definition
they are recycled
Term
how can you tell there is lipid malabsorption
Definition
fat soluble vitamins and essential fatty acids in excretion
Term
what diseases involve lipid malabsorption
Definition
cystic fibrosis and shortened bowl
Term
what type of inheritence is cystic fibrosis
Definition
autosomal recessive
Term
what is mutated in cystic fibrosis, what does this cause
Definition
CL ion channels CFTR that hydrate mucous in secretory ducts of pancreas mutations lead to viscous mucous tha blocks pancreatic enzymes needed for lipid digestion in si
Term
what are the symptoms, other than lipid malabsorption of cystic fibrosis related to lipids
Definition
delayed growth, energy deficient
Term
how is cystic fibrosis treated
Definition
with enzyme replacement and fat soluble vitamin supplements
Term
where and when are free FA most concentrated
Definition
plasma during fasting
Term
what transports free FA
Definition
serum albumin
Term
where do free FA come from
Definition
TAG in adipose or circulating lipoproteins
Term
where can free FA be consumed
Definition
most tissues
Term
where are free FA in low concentrations
Definition
tissues
Term
what are the functions of free fatty acids
Definition
membrane lipids (phospholipids, glycolipids), stored in adipose, major energy reseve
Term
what form at 90% of fatty acids in
Definition
feww
Term
what part of a fatty acid is hydrophobic
Definition
carbon chain
Term
what part of a fatty acid is hydrophillic, why
Definition
carboxyl group, at physological pH it is COO-
Term
due to the carbon end and the COO- end of fatty acids the molecule is considered to be...
Definition
amphipatic
Term
when the fatty acid is longer what does this do to the solubility
Definition
more hydrophobic, must be carried with a protein for transport, decreasing fluidity
Term
what does it mean if a fatty acid is saturated
Definition
no double bonds
Term
what does it mean if a fatty acid is unsaturated
Definition
it has one or more double bonds
Term
what conformation and pattern are double bonds in an unsaturated fatty acid
Definition
cis spaced every # carbons
Term
what do double bonds do to the physical properities of the fatty acid
Definition
reduce Tm and increase fluidity
Term
when naming what carbon do you begin numbering with
Definition
the carbonyl carbon
Term
how do you name a fatty acid
Definition
number of carbons : number of double bonds (location of double bonds)
Term
where is the alpha carbon located
Definition
next to the carbonyl, carbon 2
Term
where is the beta carbon located
Definition
carbon 3
Term
where is the gamma carbon located
Definition
carbon 4
Term
where is the omega carbon located
Definition
terminal methyl
Term
what is an alternativie way of naming fatty acids
Definition
name from the omega carbon instead of carbonyl
Term
what does it mean if a fatty acid is essential
Definition
we cannot syntheaize it
Term
what are the essential fatty acids
Definition
alpha-linolenic acid, linoleic acid, arachidonic acid
Term
what is the precursor for omega 3 fatty acid
Definition
alpha0linolenic acid
Term
what is the function of omega 3 fatty acid
Definition
growth and development
Term
what is the precursor for omega 6 fatty acid
Definition
linoleic acid
Term
what is the function of omega 6 fatty acid
Definition
prostaglandin synthesis
Term
what is the largest source of fatty acids in people
Definition
dietary
Term
what is the function o f arachadonic acid
Definition
becomes essential if linoleic acid is deficient in the diet
Term
what happens to excess dietary protein and carbs
Definition
turned into fatty acids
Term
where are the common places of de novo synthesis
Definition
liver and lactating mammary glands, some in adipose
Term
where are fatty acids made
Definition
cytoplasm
Term
what is the carbon source for fatty acid production
Definition
cytosolic acetyl CoA
Term
where does energy for fatty acid production come from
Definition
ATP
Term
where does reduction power for fatty acids production come from
Definition
NADPH
Term
how does the mitochondria make acetyl CoA
Definition
oxidizing pyruvate, beta-oxidation of long cahin CoA, catabolism of ketone bodies and some amino acids
Term
what causes FA to not be stored during FA synthesis
Definition
isocitrate dehydrogenase is inhibited by high ATP levels
Term
what is the first reaction in FA synthesis
Definition
citrate synthase turns acetyl CoA and OAA into citrate
Term
why is acetyl CoA turned into citrate in FA synthesis
Definition
because acetyl CoA cannot get through the mitochondrial membrane
Term
what happens to citrate after it crosses the membrane in fatty acid synthesis
Definition
ATP-citrate lyase cleaves it into acetyl-CoA and OAA
Term
after citrate gets turned into acetyl CoA what happens to it
Definition
ATP citrate lyase cleaves citrate into carboxylate acetyl using CO2 and ATP
Term
what causes short term activation of acetyl CoA carboxylase
Definition
citrate
Term
what causes short term deactivation of acetyl CoA carboxylase
Definition
long chain FA, AMP activated protein kinase
Term
what activates AMP activated protein kinase
Definition
AMP
Term
what inhibits AMP activated protein kinase
Definition
glucagon and epinepherine
Term
what is AMP activated protein kinase dependent on
Definition
cAMP
Term
what stimulates acetyl CoA carboxylase long term
Definition
prolonged high calorie or carbohydrate diet
Term
wat inhibits acetyl CoA carboxylase long term
Definition
low calorie or carb diet
Term
what is the function of turning acetyl CoA into caeboxylate acetyl
Definition
provides energy or carbon to carbon condensations in elongation of the FA with the help of decarboxylation
Term
what is the rate limiting step of fatty acid synthesis
Definition
acetyl CoA carboxylase
Term
how many things does fatty acid synthase do
Definition
7
Term
what are the domains of fatty acid synthase
Definition
domain for binding 4-phosphopantetheine, acyl carrier protein domain
Term
what occurs at the domain for binding 4-phosphopantetheine
Definition
it functions as an acyl carrier protein with acyl units on its terminal thiol group during fatty acid synthesis
Term
what happens at the acyl carrier protein domain
Definition
acetyl is transferred to it to CYS, malonate is transferred from malonyl CoA to it, acetyl CoA carboxylase adds CO2 to it
Term
what drives reaction between acyl CIS and malonyl CoA on acyl carrier protein
Definition
CO2 added by acetyl CoA carboxylase
Term
what remains attached to acyl carrier protein domain, what is produced
Definition
4 carbon product is attached, 3-ketoacyl is made
Term
what happens for 3-ketoacyl
Definition
converted to saturated acyl by two reductions using NADPH and dehydration making alcohol
Term
once an alcohol is made in fatty acid synthesis, how is it modified
Definition
water is removed, double bonds form between carbon 2 and 3, butyryl is made and three terminal carbons are attached to acyl carrier protein by fatty acid synthase
Term
how is a fatty acid elongated
Definition
repeat actions of fatty acid synthase at transfer of butyryl to CiS at fatty acid
Term
how many carbons are added a round of elongation
Definition
2
Term
how many times can a fatty acid be elongated
Definition
7
Term
what is the product of the actions of fatty acid synthase
Definition
palmitoyl-S-CoA
Term
what happens to palmitoyl-S-CoA
Definition
palmitoyl thioesterase cleaves thioester bond making palmitate (16:0)
Term
what happens if we need palmitate to be further elongated
Definition
palmitate goes to the smoother ER and 2 carbon units are added from malonyl CoA and reduction of NADPH, special enzymes are used for each addition
Term
where in the body are there very long chain fatty acids
Definition
brain lipids
Term
how are fatty acids desaturated
Definition
smoother ER has desaturases that desaturate long chain FA, introducing CIS usually between C9 and C10
Term
how is fatty acid stored as TAG
Definition
esterified via carbonyl group to carbons of glycerol, acid loses its charge forming neutral TAG
Term
describe the structure of TAG, what is on each carbon
Definition
carbon 1 is saturated FA
carbon 2 is unsaturated FA
carbon 3 is either
Term
describe the solubility of TAG
Definition
slightly soluble in water, cannot form micelles independently, can coalesce and form oil drops
Term
what are the building blocks in TAG synthesis
Definition
glycerol phosphate and acyl CoA
Term
what is the role of glycerol phosphate in TAG synthesis
Definition
initial acceptor of activated FA during TAG synthesis
Term
what is the role of acyl CoA in TAG sythesis
Definition
free FA must be converted to activated form
Term
what is the first step in TAG synthesis
Definition
synthesis of glycerol phosphate backbone
Term
how is glycerol phosphate made in adipose and liver
Definition
glucolytic path turns glucose into DHAP and DHAP is reduced to glycerol phosphate by glycerol kinase
Term
how is glycerol phosphate made in the liver only
Definition
glycerol kinase converts free glycerol into glycerol phosphate
Term
what is the second step in TAG synthesis
Definition
fatty acyl CoA synthase (thiokinases) turn free FA into acetyl CoA
Term
what attaches FA to backbone in TAG, what must then occur
Definition
acyl transferase, phosphatase removes phosphate
Term
what is the final step in fatty acid synthesis
Definition
acyl transferase adds third FA
Term
what is the difference between a chilomicron and a VLDL
Definition
chilomicron delivers exogenous dietary acquired lipids, VLDL delivers deo novo synthesized lipids
Term
where does NADPH for fatty acid synthesis come from
Definition
mostly hesosemonoophosphate (HMP) shunt, malate oxidation and decarboxylation by malic enzyme
Term
how does the hexosemonophosphate shunt work
Definition
G6P DH is rate limiting and irreversible, it uses NADP as a coenzyme acceptor to oxidize G6P
Term
for each hexosemonophosphate shunt round, how many NADPH are made
Definition
2
Term
what does the malic enzyme do
Definition
oxidizes and decarboxylates malate to pyruvate, NADP is a coenzyme acceptor to oxidize malate generating NADPH
Term
what does hormone sensitive lipase do
Definition
converts TAG to DAG releasing FA from TAG
Term
what does epinepherine do to hormone sensitive lipase, describe the process
Definition
it binds receptor, activates adenylyl cyclase which activates cAMP which turns on cAMP dependent protein kinase which phosphorlyates HSL activating it
Term
what does insulin do to hormone sensitive lipase, describe the process
Definition
it binds receptor, activates phosphatase which dephosphorlyates HSL, inactivating it
Term
when epinepherine is activating HSL what is it also doing in the cell
Definition
it sends cAMP to acetyl CoA carboxylase and deactivates it causing FA production from acetyl CoA to stop
Term
after HSL is activated, what happens before it can do its job with TAG
Definition
a perilipin (lipid droplet) binds to it and the lipase activity is now active
Term
what can happen to the fatty acid that is released via HSL from TAG
Definition
it can go into the tissues and be used for energy production, it can be re-esterified to lower free FA in plasma
Term
describe the path of FA from release from HSL to being used in a tissue for energy
Definition
it leaves adipocyte through wall, goes into blood, binds serum albumin, is transported to tissue, fatty acyl-CoA synthase (thypkinase) turns it into fatty acyl-CoA and it is used for energy
Term
what tissues can free FA on albumin not get dropped off at
Definition
brain and RBC
Term
how is a free FA re-esterified
Definition
glyceroneogenesis produces glycerol-3-phoshpate DH which tunrs FA into esterified FA
Term
what disease is re-esterifying FA associated with
Definition
insulin resistance type 2 diabetes and obesity
Term
what is the fate of the glycerol left over after TAG degredation
Definition
it can go to the liver be phosphorlyated and used for TAG synthesis, it can be used for glyconeogenesis or glycolysis
Term
describe the path of a glycerol released from TAG to glycolysis
Definition
glycerol-3-phoshate DH turns it into DHAP which is used for glycolysis or gluconeogenesis
Term
why can't the adipocyte metabolize its glycerol back into TAG
Definition
because it has not glycerol kinase
Term
in beta oxidation, which end are fragments removed from
Definition
carbyxyl
Term
where does beta oxidation occur
Definition
mitochondria
Term
how does a long chain fatty acid get inside the mitochondrial membrane after entering a cell for beta oxidation
Definition
LCFA CoA synthase (thiokinase) turns it into LCFA-CoA. CAT-1 turns it into acyl carnitine which is transported through by acyl carnitine translocate in exchange for carnitine
Term
once inside the mitochondria what happens to acyl carnitine
Definition
CAT II catalyzes it back to acyl-CoA
Term
how do short chain fatty acids and medium chain fatty acids get into the mitochondria
Definition
they can go through in their normal form and are changed by thiokinase into acyl CoA
Term
what inhibits CAT 1
Definition
malonyl-CoA
Term
what muscle relies on carnitine the most
Definition
muscle
Term
where does carnitine come from
Definition
diet (meat mostly), made by enzymatic path in liver and kidney with lys and met
Term
in general, what does a carnitine deficiency cause
Definition
decreased ability to use LCFA as fuel
Term
what are the congenital causes of carnitine deficiency
Definition
renal tubule reabsorption, decreased cell uptake, CAT I and II defect
Term
what occurs in a CAT I defect
Definition
decreased liver use of LCFA to make glucose in fasting
Term
what occurs in a CAT II defect
Definition
heart and skeletal m. cardiomyopathy, muscle weakness, myoglobinemia with exercise
Term
how can a carnitine deficiency be treated
Definition
avoid fastine, increase carbs, decrease LCFA in diet, eat MCFA and carnitine
Term
how many reactions are involved in beta oxidation
Definition
4
Term
how many carbons are dropped in each round of beta oxidation
Definition
2
Term
what is the first step in beta oxidation
Definition
acyl CoA DH oxidizes making FADH2
Term
what is the second step in beta oxidation
Definition
enoyl CoA hydrolyase causes hydration
Term
what is the third step of beta oxidation
Definition
3-hydroxyacyl CoA DH causes a second oxidation making NADH
Term
what is the forth step of beta oxidation
Definition
thiolytic clevage releasing acetyl CoA
Term
what links FA oxidation to gluconeogenesis
Definition
acetyl CoA is a positive allosteric effector of pyruvate carboxylase
Term
how many ATP are made from degrading 1 palmitoyl CoA
Definition
129 ATP
Term
what is the difference in beta oxidation with an even or odd nuumber of carbons
Definition
thyolytic clevage poduces a 3-carbon product, propionyl CoA
Term
what is the first step in metabolizing propionyl CoA
Definition
proponyl CoA is carboxylated by propinoyl CoA caroxylase making D-methylmalonyl CoA
Term
what is the second step in metabolizing propinoyl CoA
Definition
D-methylmalonyl CoA is converted to L-methylmalonyl CoA by methylmalonyl CoA racemase
Term
what is the last step in propinoyl CoA metabolization
Definition
l-methylmaolnyl-CoA is turned into succinyl CoA by methylmalonyl CoA mutase
Term
what does methylmaolnyl CoA mutase need to work
Definition
vitamin B12
Term
how can a vitamin B12 deficiency be detected
Definition
excretion of propinoate and methylmalonate in the urine
Term
what causes heritable methylmalonic academia and acidurica
Definition
mutase is missing, deficient, or has poor affinity for B12, inability to convert B12 to coenzyme form
Term
what are the symptoms of methylmalonic academia and aciduria
Definition
metabolic acidosis and potential for retardation
Term
what type of FA have more energy, why
Definition
saturated because they are less highly reduced, fewer reducing equlivanents are made
Term
who do you need to oxidize monounsaturated fatty acids
Definition
additional isomerase enzyme
Term
what do you need to oxidize polyunsaturated fatty acids
Definition
isomerase and reductase enzyme
Term
where are FA 22 C or longer initially oxidized
Definition
peroxisome
Term
what happens in the perixisom in very long chain fatty acid oxidation different than normal
Definition
no ATP generated
Term
what do genetic defects in peroxisome beta oxidation cause
Definition
failure to target matrix proteins to the peroxisome, Zelweger's syndrome
Term
what disease causes an inability to get VLCFA across peroxisome membrane
Definition
X-linked adrenoleukodystrophy
Term
what do all disorders with peroxisome beta oxidation cause
Definition
accumulation of VLCFA in blood and tissue
Term
what use alpha oxidation
Definition
branched chain 20 C FA phytanic acid cannot function as substrate for acetyl CoA DH because the methyl is at its beta carbon
Term
how does alpha oxidation of FA work
Definition
paytanoyl CoA a-hydrolase hydroxylates the alpha-carbon and carbon 1 and releases CO2 from phytanic acid, the 19 C pristanic acid is activated to CoA and undergoes beta oxidation
Term
what is the inheritance of refsum disease
Definition
rare, autosomal recessive
Term
what causes refsum disease
Definition
peroxisomal PhyH deficiency
Term
what occurs physiologically in refsum disease
Definition
phytanic acid accumulates in the blood and tissues
Term
what are the symptoms of refsum disease
Definition
mostly neurologic
Term
what is the treatment of regsum disease
Definition
dietary restruction
Term
what occurs in a medium chain fatty acyl CoA DH deficiency
Definition
decreased oxidation of 6-10 C FA that then accumulate and show up in urine
Term
what are symptoms of medium chain fatty acyl CoA DH deficiency
Definition
severe hypoglycemia
Term
what is the treatment of medium chain fatty acyl CoA defiency
Definition
avoid fastin
Term
what is the inheritance of medium chain fatty acyl CoA deficiency
Definition
autosomal recessive
Term
what are the ketone bodies
Definition
acetoacetate, 3-hydroxybuterate, acetone
Term
what makes ketone bodies
Definition
liver mitochondria
Term
how are ketone bodies made
Definition
beta oxidation from acetyl CoA
Term
where do acetoacetate and 3-hydroxybuterate go once made
Definition
blood then peripherial cells and tissues
Term
where does acetone go when it is made
Definition
it is a dead end product
Term
what do peripherial cells do to ketone bodies
Definition
convert them back into acetyl CoA for the TCA cycle
Term
how to ketone bodies travel in the blood
Definition
on their own, soluble
Term
when are ketone bodies made in the liver
Definition
when acetyl CoA levels superscede oxidation capacity
Term
what uses ketone bodies
Definition
extra hepatic tissues: heart skeletal muscle, renal cortex, brain if other sources are gone
Term
how do FA oxidation disorders commonly present
Definition
hypoketosis and hypoglycemia
Term
what causes hypoketosis
Definition
decreased acetyl CoA avability
Term
what causes hypoglucemia
Definition
increased reliance on glucose for energy
Term
how is hepatic acetyl CoA activated
Definition
hepatic acetyl CoA is increased and this activates pyruvate carboxylase and inhibits pyruvate dehydrogenase producing OAA, OAA is used for glyconeogenesis not TCA so acetyl CoA is channeled into ketone body synthesis
Term
how does FA oxidation have a role in gluconeogenesis
Definition
it increases NADH shifting OAA to malate
Term
how is acetoacetyl CoA made
Definition
fatty acyl Coa and 2 acetyl CoA with thiolase
Term
what does HMG CoA synthase do
Definition
combines a third molecule of acetyl Coa with acetoacyl Coa to make HMG CoA
Term
what is the rate limiting step of ketogenesis
Definition
HMG CoA synthase
Term
how is acetoacetate made
Definition
HMG CoA is cleaed to make acetoacetate and acetyl CoA
Term
how is 3-hydroxybuterate made
Definition
acetoacetate is reduced with NADH has the H donor
Term
how is acetone made
Definition
acetoacetate is spontaneously decarboxylated in the blood
Term
explain the process of ketolysis
Definition
1. 3-hydroxybuterate is oxidized to acetoacetate by 3-hydroxy buterate DH making NADH
2. acetoacetate is provided with CoA from succinyl CoA by succinyl CoA aceteacetate CoA transferase
3. acetoacetyl CoA is converted into 2 acetyl CoA
Term
what is another name for succinyl CoA aceteacetate CoA transferase
Definition
thiophorase
Term
ehere does ketolysis occur
Definition
extrahepatic cells with mitochondria, not in liver it cannot use ketone bodies
Term
why cant the liver use ketone bodies
Definition
thiophorase
Term
what is ketonemia
Definition
high ketones in the blood
Term
what is ketonuria
Definition
high ketones in the urine
Term
what disease has ketonemia and ketonuria
Definition
diametes type 1, mellitus
Term
what causes fruity smelling breath
Definition
diabetic detoacidisis, acetone
Term
what does increased ketone bodies and glucose cause
Definition
increased secretion of water and dehydration
Term
describe the structure of phospholipids
Definition
alcohol with a phosphodiester bond to diacylglycerol or sphingosine
Term
describe the polarity of phospholipids
Definition
amphipatic, polar, ionic
Term
what is the prodominate lipid of cell membranes
Definition
phospholipids
Term
what are examples of the hydrophoic portions of phospholipids
Definition
glycolipids, proteins, cholesterol
Term
what is the function of membrane phospholipids
Definition
reservoir for intracellular messengers and anchors for proteins
Term
what is the function of non-membrane bound phospholipids
Definition
components of lung surfactant and essential components of bile acting as a detergent to solublilze cholestrol
Term
describe the structure of a glycosphingolipid
Definition
glycerol back bone, 2 fatty acyl groups on C1 and C2, phosphate on C3
Term
what is the simplest glycerophospholipid
Definition
phosphatidic acid
Term
what is another name for glycerophospholipid
Definition
phosphoglyceride
Term
what are all phosphoglycerides a derivative of
Definition
phosphatidic acid
Term
describe the structure of sphingophospholipids
Definition
sphingosine backbone, long chain FA at carboxyl (palmotyl CoA), long chain FA at amino that is desaturated, phosphate group
Term
what is a sphingosine composed of
Definition
amino alcohol
Term
what are all phosphoglycerides formed from
Definition
phosphatidic acid with alcohol esterified to the carbon-3-phosphate
Term
what alcohols can be esterified to the carbon-3-phosphate of phosphoglycerides
Definition
serine, ethanolamine, choline, inositol, glycerol
Term
describe the structure of a plasmalogen
Definition
FA at C2 is repalced by an unsaturated alkyl group attached by an ether rather than an ester link
Term
describe the structure of platlet activating factor
Definition
unusual ether glycerophospholipid, saturated alkyl group eith ether link to C1, acetyl residue at C2
Term
what is the function of platlet activating factor
Definition
binds to surface receptors, triggers potent thromboitic and acute inflammatory events, activates imglammatory cells and mediates hypersensitivity, acute inflammation, anaphylactic reactions
Term
what does platlet activating factor cause to happen (in other cells)
Definition
platlets to aggregate and degranulate, neutrophils and alveolar macrophages to generate superoxide radicals
Term
what is the function of superoxide radicals
Definition
kill bacteria
Term
describe the structure of cardiolipin
Definition
two PA molecules esterified through phosphates to molecule of glycerol
Term
where is cardiolipin found
Definition
bacteria and eukaryotes
Term
where is cardiolipin in eukaryotes
Definition
inner mitochondrial membrane
Term
what is the function of cardiolipin
Definition
meintience of respiratory complexes of electron transport chain
Term
what is cardioipin recognized by, what does that make it
Definition
it is antigenic, recognized by antibodies raised against treponema pallidum
Term
what does treponemia pallidum cause
Definition
syphilis
Term
describe the structure of sphingomyelin
Definition
sphingosine backbone, unsaturated 16 C FA at C3, long chain FA at amino through amide link, C1 of spingosine esterified to phosporylcholine
Term
what is the function of sphingomyelin
Definition
make myelin fibers
Term
what is sphingomyelin a precursor for
Definition
glycolipids
Term
what is the only significant sphingophosphilipid in humans
Definition
sphingomyelin
Term
what does CDP stand for
Definition
nucleotide cytidine diphosphate
Term
what are the two ways you can activate an intermediate in phospholipid synthesis
Definition
donation of phosphatidic acid from CDP diacylglycerol to alcohol.
donation of phosphomonoester of alcohol from CDP alcohol to 1,2-DAG
Term
what is released as a side product of glycerophospholipid synthesis
Definition
cistidine monophosphate (CMP)
Term
where are most phospholipids made
Definition
smoother ER
Term
after made, where do phospholipids go
Definition
organells, plasma membrane, secreted to cell exterior by exocytosis
Term
what is the precursor for many phosphoglycerides
Definition
PA, phosphatidic acid
Term
what substrates do you need to make PA
Definition
glycerol phosphate and two fatty acyl CoA
Term
what is the only cell that cannot make phospholipids
Definition
mature RBC
Term
what does PE stand for
Definition
phosphatidylethanolamine
Term
what does PC stand for
Definition
phosphatidylcholine
Term
what are the must abundent phospholipids in eukaryotic cells
Definition
PC and PE
Term
what are the steps in producing PE and PC from pre-existing pools
Definition
1. kinase phosphorlyation of choline or ethanolamine
2. convert activated form CDP-choline. ethanolamine
3. choling-phosphate or ethanolamine-phosphate is transfered to a molecule is transfered to a molecule of diacylglycerol
Term
what phospholipids can the liver make
Definition
PC, PS, PE
Term
what does PS stand for
Definition
phosphatidylserine
Term
how do you form PC from PE or PS in the liver
Definition
PC from serum lipoproteins is secreted as bile, PS dis decarboxylated to PE by PS decarboxylase, PE is methlyated 3 times to make PC
Term
what does PS decarboxylase need to work
Definition
pyridoxal phosphate coenzyme
Term
why do we need to reutilize choline
Definition
de novo synthesis of choline in humans is not enough, choline is an essential nutrient, choline is used for synthesis of acetylcholin
Term
what is acetylcholin
Definition
a neurotransmitter
Term
what is dipalmitoylphosphatidylcholine, what is its function
Definition
surfactant that decreases surface tension in lungs, reduces pressure needed to imflate aveoli, prevents alveolar collapse
Term
what is another word for aveolar collapse
Definition
atelectasis
Term
describe the structure of DPPC
Definition
palmitate at positions 1 and 2 on glycerol
Term
what is the major lipid component of lung surfactant
Definition
DPPC
Term
what is DPPC made by
Definition
type 2 pneumocytes
Term
what causes respiratory distress syndrome
Definition
insufficient lung surfactant
Term
how can lung formation in babies be accepelated
Definition
mother takes glucocorticoids shortly before delivery
Term
how can respiratory distress syndrome be treated
Definition
natural or synthetic surfactant
Term
how can fetal lung matirity be gauged
Definition
measuring DPPC, sphingomyelin ratio in amniotic fluid
Term
what does a ratio of 2 or higher mean in lung maturity
Definition
mature, sphingomyelin synthesis has shifted to DPPC in pneumocytes
Term
where does lung maturity usually occur
Definition
32 weeks of gestation
Term
why would an adult have RDS due to insufficient surfactant
Definition
surfactant making pneumocytes are damaged by infection or trauma
Term
why is PS made
Definition
base exchange reaction between ethanolamine of PE and free serine
Term
what is PS used for
Definition
membrane synthesis
Term
is PS production reversible
Definition
yes
Term
what is PI
Definition
phosphatidylinositol
Term
describe the structure of PI
Definition
steric acid at C1 and archidonic acid on C2
Term
what is the function of PI
Definition
resivour of arachidonic acid in membranes and substrate of prostaglandin synthesis
Term
what is PI made from
Definition
free inositol and CDP-diacylglycerol
Term
describe the role of PI in signal transduction
Definition
phosphorlyation of membrane bound phosphatidylinositol makes polyphosphoinositides, degration of PIP2 by phospholipase C in response to a variety of neurotransmitters, hormones, and growth factors binding receptors, produces IP3 and DAG
Term
what does GPI stand for
Definition
glycosylphosphatidylinositol
Term
what forms GPI
Definition
covalent link between protein and Pi via a carbohydrate
Term
what is the function of GPI
Definition
bind cell surface proteins, anchor proteins allowing them to increase lateral mobility on surface of plasma membrane
Term
where are cell surface proteins bound by GPI found
Definition
in parasitic protozoans like trypanosomes and leishmania
Term
how can a protein be cleaved rom a GPI anchor
Definition
cleaved by phospholipase C releasing diacylglycerol
Term
what does a deficiency in GPI cause
Definition
hemolutic disease, paroxysmal nocturnal hemoglobinuria in hematopoietic cells
Term
how is phospharitylglycerol and cardiolipin made
Definition
CDP diacylglycerol and glycerol 3 phosphate
Term
what is cardiolipin made from
Definition
2 phosphatidic acid connected by glycerol
Term
what is the precursor for cardiolipin
Definition
phosphatidylglycerol
Term
where is phosphatidylglycerol found in large amounts
Definition
mitochondrial membranes
Term
describe the process of making cardiolipin
Definition
transfer of diacylglycerophosphate from CDP diacylglycerol to a pre-existing molecule of phosphatidylglycerol
Term
how is sphingomyelin made
Definition
palmitoyl CoA condenses with serine, CoA and CO2 released
Term
what does reduction in sphingomyelin production, what is the product at this point
Definition
NADH, sphinganine
Term
what coenzyme do you need to make sphingomyelin, where does it come from
Definition
pyrdoxal phosphate, vitamin B6 derivative
Term
describe the process of sphingomyelin production
Definition
1. sphingosine acylated at amino with a long chain FA desaturated to make cremide
2.phosphorylcholine from phosphatidylcholine is transfered to ceramide making sphingomyelin and DAG
Term
what is a major component of skin and regulates skin water permability
Definition
ceramide with a 30 C FA
Term
what type of FA does sphingomyelin of myelin sheath have
Definition
long chain like lingoceric acid, nervonic acid
Term
what FA does gray made sphingomyelin have
Definition
steric acid
Term
what degrades phosphoglcerides, where
Definition
phospholipases in all tissues and pancreatic juice
Term
what things outside the body act as phospholipases
Definition
toxins and venoms, pathogenic bacteria use it to dissolve membranes and spread infection
Term
what is sphingomyelin degraded by, what is it classified as
Definition
lysosomalphospholipase sphingomyelinase
Term
what do phospholipases do to the molecule
Definition
hydrolyze phosphodiester bonds
Term
what makes phospholipases specific
Definition
each cleaves the phospholipid at a specific spot
Term
what are the major enzymes that degrade phospholipids
Definition
phospholipase A1, A2, C, D
Term
what does lysophospholipase need as a substrate
Definition
lysphosphoglyceride
Term
how is lysphosphoglyceride made
Definition
removal of FA at C1 oe C2
Term
what is the secondary functions of phospholipases
Definition
remodel phospholipids, release molecular messengers like DAG, iP3 or substrates for synthesis of messengers
Term
what is an example of a substrate for synthesis of messengers
Definition
arachidonic acid
Term
what do phospholipase A1 and A2 do
Definition
remove specific FA from membrane bound phospholipids
Term
what replaces after A1 and A2 do its job, what enzyme facilitates this
Definition
alternative FA using acyl CoA transferse
Term
how can unique lung surfactant be made
Definition
replacing with alternativie FA after using A1 and A2 phospholipases
Term
what degrades sphingomyelin
Definition
sphingomyelinase
Term
where does sphingomyelinase come from
Definition
lysosome
Term
how does sphingomyelinase do its job, what happens to the product to complee degredation
Definition
hydrolytically removes phosphorylcholine leaving ceramide which is cleaved by cermidase into sphingosine and FA
Term
what can released sphingosine and FA function in, how
Definition
regulate signal transduction pathways by influencing activity of protein kinase C by phosphorlyating its substrates, promote apoptosis
Term
what type of inheritance is niemann-pick disease
Definition
autosomal recessive
Term
what causes niemann-pick disease
Definition
inability to degrade sphingomyelin
Term
what is deficnent in niemann-pick disease
Definition
sphingomyelinase a type of phosphilipase C
Term
what are the symptoms of type A neimann-pick disease
Definition
lipid deposits in liver and spleen, liver and spleen enlarged, sphingomyelin cannot be degraded, severe infantile
Term
what happens to infants with severe lysosomal storage disease, why
Definition
rapid neurodegeneration due to sphingomyelin in CNS deposition causing early death
Term
what are the symptoms of type C niemann-pick disease
Definition
little to no damage to neural tissue, lungs spleen liver and bone marrow affected making it chronic, life expectancy to adulthood
Term
what population is more likley to have type A neimann pick disease
Definition
ashkenazi jewish population
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