antibiotics

Question 1

selective toxicity

Answer 1

ability to kill or injure invading organisms without harming cells of host

Question 2

minimal inhibitory concentration (MIC)

Answer 2

lowest concentration of antimicrobial agent that inhibits visible growth of bacteria after 18-24 hrs of incubation

Question 3

minimal bactericidal concentration (MBC)

Answer 3

lowest concentration of antimicrobial agent that kills 99.9% of bacteria
usually higher than MIC

Question 4

beta lactam MOA

Answer 4

bind transpeptidases, preventing cross-linking of adjacent PG strands
penicillins, cephalosporins

Question 5

vancomycin MOA

Answer 5

prevents polymerization of growing PG chain by binding to terminal D-ala D-ala on pentapeptide side chain
(prevents elongation of PG chain)

Question 6

bacitracin MOA

Answer 6

blocks recycling of bactoprenol, inhibiting PG synthesis

Question 7

3 antibiotic classes that inhibit PG synthesis

Answer 7

beta lactams
vancomycin
bacitracin

Question 8

tetracycline MOA

Answer 8

binds 30S subunit

Question 9

aminoglycoside MOA

Answer 9

binds 30S subunit

Question 10

macrolide MOA

Answer 10

binds 50S subunit

Question 11

3 antibiotic classes that inhibit protein synthesis

Answer 11

tetracyclines
aminoglycosides
macrolides

Question 12

quinolone MOA

Answer 12

target bacterial DNA topoisomerase (gyrase) to prevent bacterial DNA replication and repair

Question 13

rifampin, rifabutin MOA

Answer 13

inhibit RNA synthesis via binding RNA polymerase

Question 14

metronidazole MOA

Answer 14

damage bacterial DNA

Question 15

3 antibiotic classes that inhibit nucleic acid synthesis

Answer 15

quinolones
rifampin/rifabutin
metronidazole

Question 16

only two antibiotic classes that are bacteriostatic

Answer 16

tetracyclines
macrolides
(all others are bactericidal)