Antibiotics and resistance

Question 1

3 examples of a beta lactam Abx

Answer 1

penicillin
amoxicillin
cefuroxime
piptazobactam 
co-amox

Question 2

MOA of beta lactams

Answer 2

inhibition of peptidoglycan synthesis- binds PBP

prevents cross linkage in cell wall between NAM/NAG

Question 3

4 resistance mechanisms of bacteria to beta lactams

Answer 3

cleavage of Abx by enzymes
change of PBP structure
porin loss
Abx doesn’t cross the membrane

Question 4

example of glycopeptides

Answer 4

vancomycin

Question 5

MOA of glycopeptide Abx

Answer 5

disrupts peptidoglycan cross-linking

Question 6

2 bacterial resistance mechanisms to glycopeptides

Answer 6

does not cross membrane

change target

Question 7

example of an aminoglycoside abx

Answer 7

gentamicin

Question 8

MOA of aminoglycoside abx

Answer 8

irreversibly attaches to 30s ribosome

Question 9

3 mechanisms of bacterial resistance to aminoglycosides

Answer 9

enzyme modification
mutation of binding site
reduced uptake

Question 10

example of tetracycline abx

Answer 10

doxicycline

Question 11

MOA of tetracyclines

Answer 11

blocks RNA binding to 30s ribosome

Question 12

3 mechanisms of bacterial resistance to tetracyclines

Answer 12

efflux pump
site alteration
reduced uptake

Question 13

MOA of chloramphenicol

Answer 13

prevents protein chain elongation by inhibiting the peptidyl transferase activity of the bacterial ribosome

Question 14

2 bacterial mechanisms for resistance to chloramphenicol

Answer 14

enzyme modification

reduced uptake

Question 15

2 examples of macrolide abx

Answer 15

clarithromycin

azithromicin

Question 16

MOA of macrolides

Answer 16

reversibly bind 50s ribosome and block peptide elongation

Question 17

3 bacterial mechanisms of resistance to macrolides

Answer 17

enzyme modification
mutation of site
efflux

Question 18

example of lincomycin abx

Answer 18

clindamycin

Question 19

MOA of lincomycins

Answer 19

bind 50s ribosome and blocks peptide elongation

Question 20

mechanism of bacterial resistance to lincomycins

Answer 20

mutation of site

Question 21

3 examples of quinolone abx

Answer 21

ciprofloxacin, levofloxacin, moxifloxacin

Question 22

MOA of quinolone abx

Answer 22

interrupts DNA gyrase and topoisomerases required for supercoiling of DNA- bind to alpha subunit

Question 23

mechanism of resistance to quinolone abx

Answer 23

target changes

Question 24

2 examples of nitrimidazoles

Answer 24

metronidazole

tinidazole

Question 25

MOA of nitrimidazoles

Answer 25

inhibits nucleic acid synthesis by disrupting DNA

Question 26

Mechanism of resistance to nitrimidazole abx

Answer 26

target changes

Question 27

example of rifamycin abx

Answer 27

rifampin

Question 28

MOA of rifamycin

Answer 28

binds RNA polymerase inhibiting RNA synthesis

Question 29

2 mechanisms of rifamycin resistance

Answer 29

target changes | decreased uptake

Question 30

example of sulfonamide

Answer 30

sulphamethoxazole | sulphadiazine

Question 31

MOA of sulfonamides

Answer 31

inhibits synthesis of folic acid by competing with pABA

Question 32

2 mechanisms of resistance of bacteria to sulfonamides

Answer 32

target changes | permeability

Question 33

MOA of trimethoprim

Answer 33

interferes with folic acid synthesis by inhibiting dihydrofolate reductase

Question 34

resistance mechanism of bacteria to trimethoprim

Answer 34

target changes

Question 35

how does resistance transfer between bacteria- horizontal or vertical?

Answer 35

horizontal