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Test 3- Ch. 9, 10, 14
BIOL 440
99
Microbiology
Undergraduate 1
10/22/2013

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Cards

Term
Drugs (definition)
Definition
Chemicals that affect physiology in any manner
Term
Chemotherapeutic agent
Definition
drugs that act against diseases
Term
Antimicrobial agents
Definition
drugs that treat infections (against microbes)
Term
what bacteria is the major cause of death from burns?
Definition
S. pyogenes (1/2 of all deaths)
Term
What did Paul Ehrlich and Alexander Fleming discover?
Definition
Penicillium inhibited growth of bacteria on agar plates
Term
What did Howard Florey and Ernest Chain contribute to Penicillin use? Who was their first patient?
Definition
Discovered its use in humans and perfected the purification and solubility needed to treat.
- Albert Alexander (police officer- later died)
Term
Gerhard Domagk
Definition
Discovered the use of Sulfonilamide (Prontosil) which effects folic acid synthesis which is important for nucleotide synthesis. Tested on his own child who had streptococcal infection.
Term
What are the two main categories of selective toxicity for antimicrobial action?
Definition
Structure and Function
Term
6 methods of antimicrobial action
Definition
1. Inhibition of cell wall synthesis (Penicillins)
2. Inhibition of protein synthesis (Tetracyclines)
3. Disruption of cytoplasmic membrane (Polymyxins)
4. Inhibition of general metabolic pathway (Sulfonamides)
5. Inhibition of DNA or RNA synthesis (Actinomycin)
6. Inhibition of pathogen attachment or host recognition (Arildone)
Term
Penicillin- what does it target and how does it work?
Definition
-Prevent bacteria from increasing amount of peptidoglycan
-only effects newly reproduced bacteria
-interferes with linking enzymes that connect NAM subunits. Cells eventually burst due to osmotic pressure
Term
Vancomycin and Cycloserine- what does it target and how does it work?
Definition
-targets cell wall synthesis
-Affects Alanine-Alanine bridges between NAM molecules
Term
Bacitracin- what does it target and how does it work?
Definition
-targets cell wall synthesis
-Blocks secretion of NAG and NAM from cytoplasm
Term
Isoniazid- what does it target and how does it work?
Definition
disrupt arabinogalactan-mycolic acid (acid fast bacteria) in Mycobacterial species
*use for long period of time since reproduction is slow.
Term
What step of protein synthesis do antibiotics usually target?
Definition
Translation- Can differentiate between the 70s ribosomes of the prokaryotes and the 80s ribosomes of the eukaryotes
Term
Streptomycin and Gentamicin (Aminoglycocides)- what does it target and how does it work?
Definition
-Alter 30s subunit of ribosome (protein synthesis)
-mRNA is misread because it doesn't bind normally to the small subunit before translation
Term
Tetracycline- what does it target and how does it work?
Definition
- blocks tRNA docking site (protein synthesis)
Term
Chloramphenicol- what does it target and how does it work?
Definition
-binds between amino acids (protein synthesis)
-Blocks enzymatic activity of ribosome
Term
Erythromycin (macrolide)- what does it target and how does it work?
Definition
-bind to 50s, preventing mRNA from moving through ribosome (protein synthesis)
Term
Amphotericin B (polyene)- what does it target and how does it work?
Definition
attaches to ergosterol which is a molecule similar to cholesterol found in fungal membranes. (disruption of cytoplasmic membranes)
*Toxic to humans
Term
Polymyxin- what does it target and how does it work?
Definition
-disrupts cytoplasmic membranes of G- bacteria
*toxic to kidneys so used as topical
Term
Pyrazinamides- what does it target and how does it work?
Definition
disrupts transport across plasma membrane (tuberculosis)
-Disruption of Cytoplasmic membrane
Term
Heavy metals- what does it target and how does it work?
Definition
paralyze (parasitic worms), inactivate enzymes
-Metabolic antagonists (sulfonamides- Prontosil- PABA)
-Interferes with the conversion of normal PABA to folic acid. This doesn't interfere with us because we obtain our folic acid from outside sources.
Term
Actinomycin- what does it target and how does it work?
Definition
targets replication and transcription (binds to DNA)
Term
Nucleotide analogs- what does it target and how does it work?
Definition
Block DNA replications
Term
Quinolones and fluoroquinolones- what does it target and how does it work?
Definition
Inhibit DNA gyrase which coils and uncoils bacterial DNA
-no effect on eukaryotes or viruses
Term
Rifampin- what does it target and how does it work?
Definition
binds to RNA polymerase in bacteria (M. tuberculoses)
Term
Reverse transcriptase inhibitors
Definition
HIV cocktail
Term
Amantadine & Rimantadine- what does it target and how does it work?
Definition
antiviral agent
-neutralize acidity of phagolysosome and prevent viral uncoating.
Term
efficacy-diffusion susceptibility test
Definition
antibacterial drug on disks. Plated to see how well they inhibit growth
Term
Minimum Inhibitory Concentration (MIC)
Definition
series of vials with increasing concentration of drug to identify the minimum needed to inhibit growth.
Term
Minimum Bactericidal Concentration (MBC)
Definition
min concentration to kill everything Follow up test to the MIC. Plate the clear tubes solutions to see which were killed
Term
E- test
Definition
strip of paper with increasing concentration of antibiotics. Used to identify the concentration needed to inhibit growth. Done on an agar plate.
Term
4 types of antibiotic administration
Definition
topical
oral
intramuscular
IV
Term
3 categories of antibiotic side-effects
Definition
1. toxicity (liver, kidney, pregnancy)
2. Allergies (minor --> anaphylactic shock)
3. Disrupt normal microbiota
Term
Mechanisms of Antibiotic resistance (5)
Definition
1. produce enzymes that destroy or deactivate the drug
2. slow or prevent entrance of the drug
3. alter target of drug
4. alter metabolic pathway or bypass it
5. pump the drug out
Term
cross resistance
Definition
resistance to drug with same structure
Term
antibiotic combinations (synergism)
Definition
2 or more at the same time
Term
antibiotic combinations (antagonism)
Definition
inhibition of one drug by other
Term
Thermal death point
Definition
lowest temperature that kills all cells in broth in 10 mins
Term
Thermal death time
Definition
time to sterilize volume of liquid at set temp
Term
3 types of moist heat
Definition
1. boiling (1000 C)
2. autoclaving (1210 C)
3. Pasteurization (30 min at 63 C or 15 sec at 72 C)
Ultrahigh temp sterilization (1-3 sec at 140 C)
Term
Dry Heat (2 types)
Definition
Flame (15000 C)
Ovens (171 C)
Term
Refrigeration and Freezing
Definition
low temps slow growth but don't kill unless ice crystals form
Term
Desiccation
Definition
Drying inhibits growth due to removal of water (does not kill)
Term
Lyophilization
Definition
long term preservation of microbe cultures by rapid freeze and vacuum (prevent ice crystal formation)
Term
Filtration
Definition
sterilization degree based on pore size. Does not kill, just removes.
Term
Osmotic Pressure
Definition
prevents bacterial growth
Term
Radiation- Ionizing (1nm)- 3 types
Definition
1. electron beam- good for thin layers
2. Gamma Rays- deeper penetration (can penetrate containers)
3. X-rays-deeper penetration but low energy. No practical
Term
Radiation-Non ionizing
Definition
wavelengths greater than 1nm
-excites electrons to form new bonds
-UV light causes thymine dimers in DNA but it does not penetrate well
-used for operating beds
Term
what organisms are chemical methods most effective against?
Definition
enveloped viruses
vegetative cells of bacteria, fungi, and protozoa
Term
Phenol and Phenolics (examples and how it works)
Definition
low level disinfectants (protein and plasma membrane)
-can remain active for prolonged time
-iister (carbolic acid), lysol, triclosan
Term
Alcohols (examples and how it works)
Definition
intermediate disinfectants (protein and plasma membrane)
-isopropanol, etoh
Term
Halogens
Definition
intermediate disinfectants (damage enzymes via oxidation or denaturing)
-iodine tablets, chlorine, bleach, bromine, chloramines
Term
Oxidizing Agents
Definition
high level disinfectant and antiseptic
-oxidation of microbial enzymes (peroxide, ozone for drinking water, peracetic acid for sporocide sterilizing equipment)
-hydrogen peroxide can disinfect and sterilize surfaces (not deep wounds
Term
Soap (surfactant)
Definition
hydrophilic and hydrophobic ends
-good degerming agents but not antimicrobial
Term
Detergent (surfactant)
Definition
positively charged organic surfactants- makes membranes soluble
-Zephiran
-QUATS (quaternary ammonium compounds)- colorless and tasteless- harmless to humans so used in medical and industrial applications
Term
Heavy Metals
Definition
low level agents (ions alter 3-D shape of proteins)
-thimerosal- preserve vaccines
-Copper- algal growth in reservoirs, fish tanks, etc. (interferes with chlorophyll)
-Silver Nitrate- prevent blindness caused by gonorrhea
Term
Aldehydes
Definition
-compounds with terminal -CHO groups
-denature proteins and inactivate nucleic acids (cross link with amino, hydroxyl, sulfhydryl and carboxyl groups)
-glutaraldehyde- disinfects (short exposure) and sterilizes (long exposure)
-formalin- embalming and disinfection of rooms and instruments
Term
Gaseous Agents
Definition
-ethylene oxide and propylene oxide (closed chamber)
denature proteins and DNE by cross linking functional groups
-used in hospitals and dental offices (hazardous, explosive, poisonous, carcinogenic)
Term
use-dilution test
Definition
culture metal rods with organism after 10 minutes in agent
Term
In-use test
Definition
swab before and after disinfection then plate for growth
Term
Sterilization
Definition
remove all microbes
Term
disinfection
Definition
remove many pathogens
Term
Aseptic
Definition
environment or procedure free of pathogens
Term
Antisepsis
Definition
skin, tissue
Term
degerming
Definition
physical removal, rubbing
Term
Sanitization
Definition
disinfection in public place
Term
Pasteurizatino
Definition
heat to kill pathogens
Term
-stasis/-static
Definition
halt growth , not kill
Term
-cide/-cidal
Definition
kill
Term
Etiology
Definition
study of the cause of a disease
Term
Germ theory of disease
Definition
disease caused by infections of pathogenic microorganisms
Term
Pathogenicity
Definition
ability of organism to cause disease
Term
Virulence
Definition
degree of pathogenicity (how they evade immune system and cause disease)
Term
Virulence factors (4)
Definition
1. adhesions
2. extracellular enzymes
3. toxins
4. anti-phagocytic factors
Term
Adhesions
Definition
process by which microorganisms attach themselves to cells
-specialized structures (lipoproteins or glycoproteins)
-attachment proteins (viruses)
-adhesins (bacteria)
Term
extracellular enzymes
Definition
enzymes secreted by pathogen that help pathogen dissolve structural chemicals in the body and invade further
(hyaluronidase, collagenase, coagulase, kinase)
Term
Toxins- fucntion
Definition
produced by pathogen- harm tissues or trigger host response that cause damage
-Toxemia- toxins in the bloodstream beyond the site of infection
Term
2 types of toxins
Definition
1. Exotoxins- cytotoxin, neurotoxin, enterotoxin
2. Endotoxins- Lipid A
Term
Anti-Phagocyctic Factors
Definition
1. Bacterial Capsule- composed of chemicals found in the body not recognized as foreign. Can be slippery and difficult for phagocytes to engulf
2. Anti-phagocytic chemicals- prevent fusion of lysosome and phagocytic vesicles OR destroys white blood cells (leukocidins)
Term
Benefits of normal microbiota (2)
Definition
1. antagonistic protection against pathogens
2. production of certain vitamins in the body
Term
Normal sites of microbiota
Definition
upper respiratory
digestive tract
Urinary and reproductive
skin and eyes
Term
What conditions allow resident microbiota to cause disease
Definition
immune suppression
changes in normal flora
introduction into unusual site in the body
Term
Resident Microbiota
Definition
bacteria that are a part of the normal microbiota throughout life (commensalism)
Term
Transient Microbiota
Definition
in/on the body hours to months before disappearing (same region as resident microbiota)
Term
How are transient microbiota removed? (3)
Definition
1. competition from other microorganisms
2. elimination by the body's defensive cells
3. chemical or physical changes in the body
Term
when do we acquire our normal microbiota?
Definition
during the birthing process and are established in the first months of life
Term
Axenic
Definition
womb generally free of microorganisms
Term
How do pathogens enter the body? (4)
Definition
skin
mucous membranes
placenta
parenteral route of administration (direct under the skin or mucous membrane)
Term
contamination
Definition
the presence of microbes in or on the body
Term
Infection
Definition
invasion and establishment by a pathogen
Term
Disease
Definition
pathogen alters the normal function of the body (morbidity)
Term
5 stages of infectious disease
Definition
1. incubation period (no signs or symptoms)
2. prodromal period (vague symptoms)
3. illness (most severe symptoms)
4. decline (declining symptoms)
5. convalescence (no signs or symptoms but still contagious)
Term
Reservoirs of infection (definition and 3 types)
Definition
sites where pathogens are maintained as a source of infection
1. animal
2. human carriers
3. nonliving reservoir
Term
Zoonoses
Definition
diseases that are spread from their animal reservoir to humans
-direct contact with animal or waste
-ingesting animals
-bloodsucking arthropods
Term
Human carriers
Definition
individuals who are asymptotic but infective to others
Term
Nonliving reservoirs
Definition
soil, water, food (often due to contamination by feces or urine)
Term
3 groups of disease transmission
Definition
transmission from either a reservoir or portal of exit
1. contact
2. vehicle (dust, water vapors, swimming pools, food)
3. Vector (flies and insects)
Term
Methods of classification (4)
Definition
1. body system effected
2. taxonomic groups of the causative agent
3. longevity and severity
4. how they are spread to host
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