Intro To Antibiotics

Front 1

What are the 6 modes of action for antibiotics?

Back 1

1) Nucleic Acid synthesis
2) Folic Acid Synthesis
3) DNA/RNA synthesis
4) RNA polymerases
5) Protein synthesis
6) Cell Wall synthesis

Front 2

What are the main antibiotics that go after the following and what is their targets and who do they compete with?
1) Nucleic Acids
2) Folic Acids
3. DNA/RNA synthesis

Back 2

1) Trimethoprim- inhibits thymidine
2) a. Trimethoprim- inhibits
b. Sulfonamides- compete with PABA for incorporation with folic acid
3) Quinolones/Fluoroquinolones- inhibit DNA gyrase and topoisomeraise (all xacins exept nalidixic acid)
Metronidazole

Front 3

What are the main antibiotics that go after the following and what is their targets and who do they compete with?
1) RNA polymerase
2) Protein Synthesis

Back 3

1. Rifampin and Rifabutin
2) Those that attack 30s ribosome:
a. Aminoglycoside (mycins)
b. Tetracyclines (cyclines)
Those that attack 50s ribosome:
i. Clindamyciin
ii.Chloramphenicol
iii. Oxazlidinones- Linezolid
iv. Macroaslides (Erythromysins: Dirithromysin, Azithromysin, Clarithromycin, and Telithromysin)
v. Streptogramins- (Quinupristin, Dalfopristin)

Front 4

What are the main antibiotics that go after the following and what is their targets and who do they compete with?
1) Cell Wall synthesis

Back 4

1. Glycopeptides- Vancomycin
2. Isoniazid- Mycobacterial
3. Polypeptides- Bacitracin
4. Pennicilin- (B-Lactams, Cephalosporin, Cephamycin, Carbapenems "penem"

Front 5

What are 4 main bacterial mechanisms of resistance to Antibiotics?

Back 5

1) Inactivation of Ab by Hydrolysis-
2) Inactivation of Ab by chemical modification
3) Mutation or gene alterations- change ribosome binding sites
4) Altered permeability- prevents accumulation of site action

Front 6

Describe two specific ways that bacteria inactivate antibiotics by antibiotic hydrolysis?

Back 6

Two different ways for different Antibiotics categories

1. use enzymes called B-lactamases to destroy B-lactam ring (Penicillins)
2. Gram (-) bacteria produce ESBL- which are extended spectrum b-lactamases... (greater resistence)

Front 7

Describe specific ways that bacteria inactivate antibiotics by chemical modification...

Back 7

acetylation, phosphorylation, adenylation disruptions Ab ability to bind to ribosome

Front 8

Describe specific ways that bacteria inactivate antibiotics by mutations or gene alterations

Back 8

Mutations to target sites can alter the binding shapes and Ab can not bind...
a. mecA gene
b. Erm - mutation to 50s binding

Front 9

Describe specific ways that bacteria inactivate antibiotics by altered permeability of bacteria

Back 9

decreased influx- increased eflux of cell membrane prevents Ab from entering to attack DNA gyrase

Front 10

What are two ways of determining if an antibiotic works?

Back 10

1. MIC (minimal inhibitory concentration)- Ab is diluted and measured in a cup and the smallest amount of it needed to inhibit growth of bacteria is measured
2. MBC minimal bactericidal concentration- take all concentrations of cups that showed no growth from MIC and spread samples on agar, minimum amount that shows no growth after 18-24 hrs is bacteria killer --> Also allows you to know if antibiotic is bacteriostatic or bacteriocidal

Front 11

What does bacteriostatic and bacteriocidal mean?

Back 11

If MBC is 4x higher than MIC call the antibiotic bacteriostatic because you know it only inhibits growth (long enough for immune system to kill) if MIC = MBC then it is called Bacteriocidal (Ab can kill bacteria)

Front 12

What is the most common bacterial causes of infectious diseases listed:
1) Blood (bacterial sepsis)
2) Skin infection
3) Osteomyelitis

Back 12

1. E. coli
2. S. aureus
3. S. aureus

Front 13

What is the most common bacterial causes of infectious diseases listed:
1. Respiratory: Otitis externa
2. Stomach ulcer
3. Food poisoning
4. UTI
5. Vaginitis

Back 13

1. P. aeruginosa
2. Helicobacter pylori
3. S aureus
4. Garnerella vaginalis