Antibacterial Agents-Disrupt Cell Wall

Question 1

Penicillins

Answer 1

Bind PBPs can be combined with B-lactamase inhibitors

Question 2

Cephalosporin

Answer 2

Bind PBPs- wider spectrum than penicillins, resistant to B-lactamases and better pharmacokinetic properties

Question 3

Cephamycin

Answer 3

Bind PBPs- wider spectrum than penicillins, resistant to B-lactamases and better pharmacokinetic properties

Question 4

Carbapenems

Answer 4

Broad spectrum- Bind PBPs
A carb-ase= Klebsiella pneum (KPC)-Hodge test
B carb-ase= New Delhi metallo-B-lact (NDM)
D carb-ase= in Acinetobacter resistent to nearly all antibio

Question 5

Monobactams

Answer 5

Narrow spectrum- Bind PBPsonly against aerobic gram negative

Question 6

Vancomycin

Answer 6

prevents cross linkage used for “oxacillin-res staph” and B-lactam res gram positives (too large of molecule to work with gram neg)– resistance comes from genes vanA, vanB which change pentapeptide terminus

Question 7

Daptomycin

Answer 7

binds directly to and depolarizes cytoplasmic membrane (cannot penetrate wall of Gram Neg)

Question 8

Bacitracin

Answer 8

stops movement of peptidoglycan precursors (not effective on Gram Neg)

Question 9

Polymyxins

Answer 9

Insert into membranes, increasing permeability. B and E (coliston) can cause serious nephrotoxicity

Question 10

Isoniazid*

Answer 10

inhibits mycolic acid synth in replicating mycobacteria

Question 11

Ethionamide*

Answer 11

derivative of INH also inhibits mycolic acid synth

Question 12

Ethambutol*

Answer 12

interferes with arabinogalactan synthesis

Question 13

cycloserine*

Answer 13

inhibits cell wall catalyzers

Question 14

Extended Spectrum B-Lactamases ESBLs

Answer 14

point mutations in SHV-1 and TEM-1 (class A B-lactamases) are encoded on plasmids and cause B-lactamase activity against ALL Penicillins and Cephalosporins