• only in G- bacteria
• endotoxin is the outermost layer of G- outer membrane
• 3 parts:
• Lipid A (toxic part) - forms half of lipid bilayer of outer plasma membrane
• core polysaccharide
• O specific polysaccharide- may interfere with phagocytosis or with complement binding to cell (role varies)

What are

• viroids?
• prions?
• oncoviruses?

• Viroids- plant pathogens. Don't code for proteins, but can be replicated. Are spread via pollen and seeds. Ex- Hepatitis D.
• Prions - proteins on plasma membranes throughout the body. Cause disease if one protein misfolds, causing following proteins to misfold. Prions pile up and form clumps, destroying neural tissue and create hole in the brain. Ex- mad cow disease
• Oncoviruses - mutate critical genes, such as ones that time cell division. Cause cancer.

• mRNA, carrying instructions for protein, travels to a ribosome, which then travels to RER to "read" protein code
• Amino acid chain from ribosome drops into the RER and folds into the protein
• Protein moves to Golgi body for sorting and processing, then moves to plasma membrane for exportation

Candida

• causes thrush and yeast infections
• normally found in mucous membrane but causes disease when overpopulated (usually due to broad-spectrum antibiotics)

H. casulatum

• found in soil, bird and bat droppings
• affects the lungs
• disseminated histoplasmosis mostly affects cancer and AIDS patients
• fatal if left untreated

• Pneumocystis jirovecii (previously P. carinii) was rare before AIDS epidemic and alerted health officials of a new pathogen when infections began rising suddenly

Aspergillus

• found everywhere in environment, though most people are naturally immune
• asthmatics more likely to be allergic
• Aspergillosis disease affects people with low defenses (burn victims, cancer patients, immunocompromised patients, etc), fatal if left untreated

C. immitis

• cause of valley fever
• usually affects persons with occupations involving stirring up dust

Cocci (circles)

• diplococci - two
• tetrads - four
• sarcinae - eight
• staphylococci - clusters
• streptococci - chains

Bacilli (rods)

• diplobacilli - two
• streptobacilli - chain
• palisides - side by side

Spirilla (corkscrew) - no particular arrangement

"Other"

What are

• glycocalyces?
• fimbriae?
• axial filaments?
• flagella? (4 types)

Glycocalyx - sticky capsule around bacterial cell, makes it hard for phagocytes to grab onto it

Fimbriae - hair-like extensions that help cell cling to surfaces

Axial filaments - like fimbriae, but close to cell, in bacterial envelope. Effective at moving through mucus

Flagella - move the cell

• monotrichous - one flagella
• lophotrichous - cluster of flagella at one end
• amphitrichous - flagella at both ends
• peritrichous - flagella all around cell

5 ways antibodies fight disease

("NAPCO")

• Neutralization - Ab's stick to pathogen so it can't enter cells
• Agglutination - Ab's stick to pathogens, foreign particles, and themselves, forming a clump that's quicker for phagocyte to ingest
• Precipitation - like aglutination, but allows quicker elimination of molecules, like toxins 
• Complement fixation - complement binds to Ab's stuck around a pathogen, activating complement pathway
• Opsinization - ("to make tasty") makes it easier for macrophage to grab onto slippery cells

What is the structure of

• plasma membrane?
• bacterial envelope?

Plasma membrane

• lipid bilayer - 2 layers of phoshpholipids with their fatty acids facing each other

Bacterial envelope

• the plasma membrane
• the cell wall
• the periplasm (gel-like substance outside of plasma membrane)
• G+ have simple envelope, with above structures
• G- have complex envelope; the cell wall floats in periplasm. Another lipid bilayer surrounds that. This makes them harder to treat.

DNA - codes for proteins and directs all genetics and heredity of a cell

Ribosomes - conducts protein synthesis

Cytoplasm - fills cell

Plasma membrane - controls what enters and exits the cell

Live attenuated

vs

Inactivated vaccines

Live attenuated vaccine

• made with live pathogen that has been modified so that it can't cause disease
• Pros: almost identical immunity as natural, only one dose is needed
• Cons: dangerous to immunocompromised persons, rendered ineffective to those with passive immunity, easily rendered ineffective by heat and light

Inactivated vaccine

• entire pathogen is used, but is inactivated by chemicals or heat OR
• made of part of a pathogen (an antigen, its toxin, or polysaccharides)
• Pros: can be used on immunocompromised persons, isn't rendered ineffective by presence of existing antibodies from passive immunity
• Cons: multiple doses must be given, only provides humoral immunity (not many memory cells produced), immunity declines over time

What are

• Plasma cells?
• B lymphocytes (B cells)?
• T lymphocells (T cells)?

Plasma cells - protein factories that make huge quantities of antibodies during an immune response

B cells - make and secrete antibodies

T cells

• Cytotoxic T cells - insert perforins into foreign cell, causing it to burst
• Suppressor T cells - slowly turn off immune response when it's done its job
• Help T cells - produce lymphokines

What are

• antigens?
• antibodies?
• lymphokines?

• Antigens - any molecule that produces an immune response
• Antibodies proteins made by B cells that attach to antigens
• Lymphokines - chemical cells that activate other cells in an immune response

• Hemolysins - attack RBC's
• Leukocydins - attack WBC's
• A & B toxins - "A" attaches to cell while "B" enters cell
• Superantigens -
• Enterotoxins - cause diarrhea, can lead to septic shock
• Botulin neurotoxin - blocks acytylcholine from neuromuscular junction
• Tetanus toxin - inactivates neurons
• Exfoliatin toxin - seperates epidermal layers (SSSS- staphylococcal scalded skin syndrome)

• Make a slippery capsule that makes it harder for phagocytes to grab onto them
• Evolve way to survive inside a phagocyte
• Evolve ways to obtain iron
• Change their antigens
• Cover themselves in our own molecules so they aren't recognized as "foreign"
• Make substances that interrupt chemotaxis

Caused by dermatophytes, which depend on keratin for their nutrition (which is why they rarely invade deeper tissues)

Treated with superficial creams:

• tinea corporis (mild infections) - ringworm of the smooth areas of the skin
• tinea pedis - ringworm of the feet, "athelete's foot"
• tinea cruris - ringworm of the groin, "jock itch"

Treated with oral drugs:

• tinea corporis (severe infections)
• tinea capitis - ringworm of the scalp
• tinea unguium - ringworm of the nails, "fungal nails"
• tinea barbae - ringworm of the beard