Antibiotics: Mech of action

Question 1

antimetabolites: sulfonamide, trimethoprim

Answer 1

inh synthesis of DHF and nucleic acid aynthesis

Question 2

antimetabolite: flucytosine

Answer 2

inh thymidylate synthetase and DNA synthesis

Question 3

isoniazid

Answer 3

inh synthesis of mycolic acid (for mycobacteria)

Question 4

B-lactam, penicillin, cephalosporin

Answer 4

interfere with cell wall biosynthesis
inh of transpeptidase weakens wall
autolytic

Question 5

cycloserine, bacitracin, glycopeptide, vancomycin, teichoplanin, capsofungin

Answer 5

interfere with cell wall biosynthesis

Question 6

polymyxins, polyenes nystatin, amphotericin B, daptomycin

Answer 6

disrupt membrane integrity

Question 7

aminoglycosides: streptomycin

Answer 7

inh protein synthesis by binding to 30S ribosomal subunit

Question 8

aminoglycosides: gentamicin, kanamycin, neomycin, amikacin, tobramycin

Answer 8

bind to 30S at multiple sites and inh protein synthesis

Question 9

tetracycline

Answer 9

block protein synthesis by inh binding of AA t-RNA to 30S

Question 10

erythromycin, azithromycin, clindamycin, chloramphenicol

Answer 10

bind to 50S and inh protein synthesis at chain elongation step

Question 11

oxazolidinones: linezolid

Answer 11

bind rRNA on 30S and 50S

Question 12

streptogramins: dalfopristin, quinupristin

Answer 12

bind to 50S

Question 13

mupirocin

Answer 13

binds isoleucyl-tRNA synethetase and affects protein synthesis

Question 14

fluoroquinolones: ciprofloxacin

Answer 14

inh bacterial DNA gyrase

Question 15

nitroimidazoles

Answer 15

fragment DNA

Question 16

rifampin

Answer 16

binds to bacterial RNA pol and blocks transcription

Question 17

azoles: fluconazole, ketoconazole

Answer 17

inh ergosterol synthesis

Question 18

ethambutol

Answer 18

TB

Question 19

pyrazinamide

Answer 19

TB