Antibiotics

Question 1

5 ways antibiotics mess up bacterial pathogens

Answer 1

1. Target cell wall peptidoglycans
2. Outer + cytoplasmic microbials (polymyxin)
3. Inhibit ribosomal protein synthesis
4. Inhibit replication/transcription
5. Anti-metabolites

Question 2

Two B-lactams

Answer 2

cepalosporin, penicillin

Question 3

B-lactam mechanism of action

Answer 3

Prevents peptidoglycan linkage (gylcosidic bond) between N-acetylmuramine and N-acetylglucosamine

Question 4

vancomycin

Answer 4

inhibits utilization of lipid-linked intermediate to inhibit ELONGATION of peptidoglycan chain

Question 5

cycloserine

Answer 5

inhibits alanine racemase, which prevents production of muramyl pentapeptide

Question 6

polymyxin

Answer 6

cationic surfactants disrupts outer and cytoplasmic membrane of cell wall

Question 7

aminoglycosides

Answer 7

interfere with 30s subunit to inhibit translation

Question 8

tetracyclines

Answer 8

inhibit aminoacyl tRNA from binding 30S subunit

Question 9

chloroamphenicol

Answer 9

binds to 50S subunit to inhibit peptidyl transferase

Question 10

macrolides + linomycins

Answer 10

bind 23S unit of ribosomal RNA and 50S unit of peptidyl transferase

Question 11

quinoline

Answer 11

inhibit DNA gyrase and topoisomerase

Question 12

rifampcin

Answer 12

inhibits RNA polymerase (blocks “pooper”)

Question 13

sulfonamide

Answer 13

analog to p-amino-benzoic acid, needed for folic acid synthesis. Bacteria make folic acid, which is where we get our folic acid. Thus sulfonamide selectively kills bacteria.

Question 14

trimethoprim

Answer 14

selectively inhibits dihydrofolate reductase 50,000:1 in bacteria - eukaryote

Question 15

isoniazid

Answer 15

inhibits lipid synthesis in myobacteria

Question 16

metronidazole

Answer 16

interferes with anaerobic metabolism