antimicrobials II

Question 1

antimicrobial targets: 4

Answer 1

inhibit nucleic acid synthesis, disrupt cell wall synthesis, inhibit protein synthesis, and disrupt metabolic pathways

Question 2

beta lactams: do what?

Answer 2

inhibit peptidoglycan synthesis = disrupt cell growth and division

Question 3

penicillin binding proteins: what and do what?

Answer 3

enzymes (serine proteases) that catalyze the cross linking of peptidoglycan layers

Question 4

penicillin binding proteins: named according to?

Answer 4

molecular weight (higher number = larger)

Question 5

beta lactams and PBPs?

Answer 5

bind to PBPs, interfere with their action, disrupt cell wall synthesis and ultimately lead to osmotic lysis of cell

Question 6

activity of a particular beta lactam depends on?

Answer 6

drug affinity for specific PBPs that are most critical for that organism’s growth and cell division

Question 7

4 types of beta lactams

Answer 7

penicillins. cephalosporins. carbapenems. monobactams.

Question 8

what is common in beta lactams?

Answer 8

4 ring square structure with nitrogen

Question 9

4 types of penicillins (in order of increasing gram neg coverage)

Answer 9

natural penicillins, semi-synthetic penicillins, amino penicillins, ureidopenicillins

Question 10

4 formulations of natural penicillins

Answer 10

aqueous: IV admin. phenoxymethyl for oral. procaine for IM. benzathine for depot injection