Beta-lactams Flashcards
gram positive cell walls are ___ complex than gram negative
less
binding of beta-lactam antibiots to PBP-1 leads to
cell lysis
binding of beta-lactam antibiotics to PBP-2 leads to
oval cells deficient in rigidity and inhibits division
binding of beta-lactam antibiotics to PBP-3 leads to
abnormally long filamentous shapes and failure to produce a spetum
binding of beta-lactam antibiotics to PBP-4-5 leads to
no lethal effects
gram positive secrete the enzyme beta-lactamase ___ of the cell
outside
the gram negative cell wall is ___ complex than the gram positive
more
what type of penicillin can be administered orally due to it being able to survive passage through the stomach?
acid resistant penicillin analogues
what characteristic of acid resistant penicillin analogues allows it to survive passage through the stomach and be orally administered?
EWG attached to the side chain carbonyl
are penicillins bacterostatic or bactericidal
bactericidal
what is the overall result of the MOA of penicillins?
CWT is permanently inhibited and the cell wall is defective (bactericidal)
why is methicillin more resistant to Beta-Lactam?
Is consists of a bulky R group which shields the carbonyl and creates more resistance
penicillin is active against gram ___
positive
penicillin G is taken ___ and penicllin V is taken ___
intravenously/orally
methicillin is primarily used for ____ due to it’s narrower spectrum and decreases potentcy
MRSA
which penicillin derivative can treat gram positive and negative organisms and it most associated with drug induced rash?
Ampicillin
which class of Beta-lactamase inhibitors are mechanism-based enzyme inhibitors?
class 1
which class of beta-lactamase inhibitors possess broad spectrum antimicrobial activity?
class 2 (carbapenems)
clavulanic acid is an _____ inhibitor of beta-lactamase
irreversible
Sulbactam is an example of a class __ beta-lactamase inhibitor
1
tazobactam sodium is more potent than sulbactam and is an example of a class ___ beta lactamase inhibitor
one
what IV class 2 beta-lactamse inhibitor exhibits broader antimicrobial spectrum and greater potency than any other beta-lactam antibiotic and is used in combination with Cilastatin to treat UTI’s?
imipenem
are cephalosporins bacteriostatic or bactericidal?
bactericidal
what generation of cephalosporins are primarily active against gram positive cocci and are not shown to be effective against MRSA?
first generation
which generation of cephalosporins show gram positive and gram negative activity?
second generation
which generation of cephalosporins are primiarily used to treat multi-drug resistant nosocomial infections?
third generation
____ chemical instability is associated with beta-lactam hydrolysis
cephalosporin
first and second generation cephalosporins
demonstrate ____ beta-lactamase resistance
poor/average
