L5 Cushman

Question 1

2 main structures for aminoglycosides

Answer 1

streptidine and 2-deoxystreptamine

Question 2

aminoglycoside MOA

Answer 2

bind to 30S and inhibit protein synthesis. also bind to 16S (part of 30S) rRNA forming THE A SITE. interferes with INITIATION COMPLEX*

Question 3

selection of wrong amino acids during 30S binding from aminoglycosides causes something known as

Answer 3

“nonsense proteins”

Question 4

T or F:
aminoglycosides cause a frame shift in bacterial cell wall as a part of its mechanism

Answer 4

true

Question 5

T or F:
aminoglycosides have a negative charge

Answer 5

false, positive which lets them through the outer membrane (polarity)

Question 6

T or F:
aminoglycoside passage through cytoplasmic membrane is a passive transport process due to its positive charge

Answer 6

false, it is ACTIVE TRANSPORT

Question 7

resistance mechanisms for aminoglycosides (3)

Answer 7

• metabolism: bacteria inactive aminoglycosides by acetylation, adenylation, and phosphorylation
• altered ribosomes
• altered aminoglycoside uptake: altered target site/mutation in target site (i think)

Question 8

all aminoglycosides have which two toxicities

Answer 8

ototoxicity (irreversible) and nephrotoxicity (reversible)

Question 9

aminoglycosides can also cause respiratory paralysis, how do you treat this?

Answer 9

neostigmine or calcium gluconate

Question 10

aminoglycosides are used for their activity against gram ____ bacteria in practice

Answer 10

negative

Question 11

T or F:
aminoglycosides are often used in combo with penicillins

Answer 11

true

Question 12

tuberculosis:
A. tobramycin
B. Gentamycin
C. Steptomycin
D. Neomycin

Answer 12

C

Question 13

most important aminoglycoside

Answer 13

gentamycin

Question 14

widely used parenterally to treat gentamycin-resistant Pseudumonas aeruginosa
A. tobramycin
B. Gentamycin
C. Streptomycin
D. Neomycin

Answer 14

A

Question 15

used topically in burn patients
A. tobramycin
B. Gentamycin
C. Steptomycin
D. Neomycin

Answer 15

B

Question 16

what are the 4 orally used aminoglycosides

Answer 16

neomycin B
paromomycin
streptomycin
Plazomicin

Question 17

treat amoebic dysentery and tapeworms
neomycin B
paromomycin
streptomycin
Plazomicin

Answer 17

paromomycin

Question 18

against bubonic plague and TB
neomycin B
paromomycin
streptomycin
Plazomicin

Answer 18

streptomycin

Question 19

treat complicated UTIs (including pyelonephritis)
neomycin B
paromomycin
streptomycin
Plazomicin

Answer 19

Plazo

Question 20

what class is erythromycin

Answer 20

macrolide

Question 21

what is the important part of the structure of macrolides for activity

Answer 21

desosamine sugar

Question 22

macrolide antibiotics are ________

Answer 22

polyketides

Question 23

what is the easy way to identify a macrolide structure

Answer 23

the polyketide is alternating methyl groups

Question 24

pka of erythromycin

Answer 24

8.8

Question 25

macrolide MOA

Answer 25

inhibit bacterial protein synthesis by binding the P site of bacterial ribosome. mainly involves binding 23S and not the protein itself.

Question 26

T or F: macrolides primarily bactericidal

Answer 26

false, bacteriostatic

Question 27

macrolides tend to accumulate within ___________ and are actually transported into the site of infection

Answer 27

leukocytes

Question 28

resistance mechs for macrolides (4)

Answer 28

- lactone ester hydrolase induced to degrade macrolides - drug-induced production of RNA methylase - mutation of adenine to guanine at A2058*** - an efflux pump ejects drugs from cell by ACTIVE transport**

Question 29

___________ spp and ________ spp exhibit intrinsic resistance by not allowing entry of macrolides

Answer 29

pseudomonas + enterobacter

Question 30

what kind of chemical reaction can inactivate the parent molecule under acidic conditions for macrolides

Answer 30

acid-catalyzed ketal formation

Question 31

what drug is administered as enteric coated tabs

Answer 31

oral erythro

Question 32

if you make a macrolide more stable in acid what does this mean for admin

Answer 32

better oral absorption

Question 33

main route of erythromycin metabolism

Answer 33

demethylation in liver

Question 34

T or F: erythomycin and clarithromycin inhibit 3A4

Answer 34

true

Question 35

erythromycin is primarily used for infections of ____ and ____ _______ primarily caused by GP bacteria

Answer 35

skin and soft tissue

Question 36

unique side effect of macrolides

Answer 36

SJS*

Question 37

erythromycin is absorbed (slowly/rapidly) and diffuses into most tissues and _________

Answer 37

rapidly, phagocytes

Question 38

_____ provide a very efficient drug delivery mechanism for erythromycin

Answer 38

phagocytes (again)