EXAM 4: NSG 531 RUSH - ADVANCED
PHARMACOLOGY - NSG 531, 2025/2026
WITH CORRECT/ACCURATE ANSWERS
Describe the difference between gram positive and gram negative
- CORRECT-ANSWERS--positive - you have a lipid bilaryer that is
normal, then on top of it you have a cell wall that is made up of
peptidoglycens - sugar peptides
on top of that layer there is nothing - more water soluble purple
dye gets through
negative is the same but the peptidoglycen layer is theinner and
then on top there is another plasma membrane - this one has a
lot of lipopolysaccarides embedded so the dye cannot penetrate it
- not very water soluble
drugs that have to get through gram negative have to go through
the extra layer
Steps of peptidoglycan synthesis - CORRECT-ANSWERS--1.
monomer synthesis
2. polymerization
3. cross-linking
Inhibitors of monomer synthesis - CORRECT-ANSWERS--
Fosfomycin - inhibits enzyme that links protein (peptido) to sugar
complexes (glycan)
,Bacitracin - inhibits dephosphyrilation step in monomer synthesis
inhibitors of monomer polymerization - CORRECT-ANSWERS--
vancomycin - prevents monomer chain elongation
so it binds to the monomer at the point of attachment to the next
monomer and prevents elongation
can cause red man syndrome
inhibitors of polymer cross-linking - CORRECT-ANSWERS--beta-
lactams (penicillins, cephalosporins, cabapenems)
form covalent bonds with bacterial transpeptidases which
mediate formation of cross linkages
synergize with aminoglycosides - they disrupt bacterial cell wall
and make it more permeable to aminoglycoside entry
MOA of inhibitors of polymer cross-linking - CORRECT-ANSWERS--
polymers are not yet cross linked
bacterial transpeptidase (aka penicillin binding protein) in the
absence of drug binds to the polymers and mediates the
formation of cross linking
leads to layers in the cell wall
if penicillin binds to it, it is not able to bind to the polymers to aid
in cross linking
what has broader spectrum to gram positive and negative cells?
Water or Fat soluble? - CORRECT-ANSWERS--fat soluble
, Antibiotic resistance in inhibitors of polymer cross-linking -
CORRECT-ANSWERS--could be related to reduced affinity for
bacterial transpeptidase or plasmids that encode for beta
lactamase - there is a genetic mutation that alters the shape of
the transpeptidase so that the drug doesn't bind to it as well
mutations can alter ability of drug to bind to bacterial
transpeptidase and reduce its effectiveness
plasmids can encode for beta lactamase which cleaves the beta
lactam
penicillin resistance - CORRECT-ANSWERS--beta lactamases
cleave penicillin so that cross-linking still takes place because
penicillin will not bind to the receptor
Beta-lactamase inhibitors - CORRECT-ANSWERS--augmentin,
unasyn, zosyn
these are combo drugs that try to overcome the genes in the
bacteria that code for the beta lactamase that will keep the drug
from binding to the receptor to inhibit cross linking
fungal ergosterol synthesis inhibitors - CORRECT-ANSWERS--
azoles
bind to and inhibit a fungal p450 enzyme involved in ergosterol
synthesis
can also bind to human enzymes
resistance d/t p450 mutations or upregulation of drug efflux
pumps
PHARMACOLOGY - NSG 531, 2025/2026
WITH CORRECT/ACCURATE ANSWERS
Describe the difference between gram positive and gram negative
- CORRECT-ANSWERS--positive - you have a lipid bilaryer that is
normal, then on top of it you have a cell wall that is made up of
peptidoglycens - sugar peptides
on top of that layer there is nothing - more water soluble purple
dye gets through
negative is the same but the peptidoglycen layer is theinner and
then on top there is another plasma membrane - this one has a
lot of lipopolysaccarides embedded so the dye cannot penetrate it
- not very water soluble
drugs that have to get through gram negative have to go through
the extra layer
Steps of peptidoglycan synthesis - CORRECT-ANSWERS--1.
monomer synthesis
2. polymerization
3. cross-linking
Inhibitors of monomer synthesis - CORRECT-ANSWERS--
Fosfomycin - inhibits enzyme that links protein (peptido) to sugar
complexes (glycan)
,Bacitracin - inhibits dephosphyrilation step in monomer synthesis
inhibitors of monomer polymerization - CORRECT-ANSWERS--
vancomycin - prevents monomer chain elongation
so it binds to the monomer at the point of attachment to the next
monomer and prevents elongation
can cause red man syndrome
inhibitors of polymer cross-linking - CORRECT-ANSWERS--beta-
lactams (penicillins, cephalosporins, cabapenems)
form covalent bonds with bacterial transpeptidases which
mediate formation of cross linkages
synergize with aminoglycosides - they disrupt bacterial cell wall
and make it more permeable to aminoglycoside entry
MOA of inhibitors of polymer cross-linking - CORRECT-ANSWERS--
polymers are not yet cross linked
bacterial transpeptidase (aka penicillin binding protein) in the
absence of drug binds to the polymers and mediates the
formation of cross linking
leads to layers in the cell wall
if penicillin binds to it, it is not able to bind to the polymers to aid
in cross linking
what has broader spectrum to gram positive and negative cells?
Water or Fat soluble? - CORRECT-ANSWERS--fat soluble
, Antibiotic resistance in inhibitors of polymer cross-linking -
CORRECT-ANSWERS--could be related to reduced affinity for
bacterial transpeptidase or plasmids that encode for beta
lactamase - there is a genetic mutation that alters the shape of
the transpeptidase so that the drug doesn't bind to it as well
mutations can alter ability of drug to bind to bacterial
transpeptidase and reduce its effectiveness
plasmids can encode for beta lactamase which cleaves the beta
lactam
penicillin resistance - CORRECT-ANSWERS--beta lactamases
cleave penicillin so that cross-linking still takes place because
penicillin will not bind to the receptor
Beta-lactamase inhibitors - CORRECT-ANSWERS--augmentin,
unasyn, zosyn
these are combo drugs that try to overcome the genes in the
bacteria that code for the beta lactamase that will keep the drug
from binding to the receptor to inhibit cross linking
fungal ergosterol synthesis inhibitors - CORRECT-ANSWERS--
azoles
bind to and inhibit a fungal p450 enzyme involved in ergosterol
synthesis
can also bind to human enzymes
resistance d/t p450 mutations or upregulation of drug efflux
pumps
