MOAs Flashcards
MOA of beta lactams
inhibition of cell wall synthesis
MOA of vancomycin
inhibits bacterial cell wall synthesis, synthesis and assembly during the second state of cell wall synthesis, and prevents cross-linking and further elongation of peptidoglycan
MOA of Synercid
on the 50s ribosomal subunit; bacteriostatic alone and in combo
MOA of oxazolidinones
bind ot the 50S ribosomal subunit near the surface interfaces of the 30S subunit, inhibiting protein synthesis; bacteriostatic
MOA of daptomycin
cyclic lipopeptide that binds to bacterial membranes and dabs lipophilic tail into cell wall; rapid, concentration dependent bactericidal activity
MOA of lipoglycopeptides
interfere with the polymerization and cross-linking of peptidoglycan by binding to the D-Ala-D-ala terminus
oritavancin and telavancin also bind to bacteria membranes and insert their lipophilic tails into th ecell wall to form a transmembrane channel like dapto, resulting in bacteria cell death
MOA of FQs
inhibition of DNA synthesis by binding to and inhibiting bacterial topoisomerases (target DNA gyrase in gm - and topo IV in gm +)
inhibition of DNA gyrase prevents relaxation of positively supercoiled DNA
inhibition of topo IV interferes with separation of chromosomal DNA
what does inhibition of DNA gyrase do?
FQs; prevents relaxation of positively supercoiled DNA
what does inhibition of topo IV do?
FQs; interferes with separation of chromosomal DNA
MOA of macrolides
reversibly bind to the 50S ribosomal subunit so that protein synthesis is suppressed and bacterial growth is inhibited (bacteriostatic)
MOA of aminoglycosides
irreversibly bind to the 30S ribosomal subunit, which results in disruption of initiation of protein synthesis, decrease in protein synthesis and misreading of messenger RNA (bactericidal, though slow)
MOA of tetracyclines
inhibit bacterial protein synthesis by reversibly binding to the 30S ribosome, blocking binding of amino-acyl tRNA to the A site on the mRNA ribosomal complex. this prevents the addition of amino acid residues to the elongating peptide chain (bacteriostatic)
MOA of tetracycline analogs
same as tetracyclines (bacteriostatic)
MOA of bactrim
produce sequential blockade of microbial folic acid synthesis (bactericidal):
SMX completely inhibits PABA into folic acid by inhibiting dihydropteroate synthetase, which inhibits the formation of dihydrofolic acid.
TMP inhibits the activity of bacterial dihydrofolate reductase to prevent the reduction of dihydrofolate to tetrahydrofolate
MOA of polymyxins
prodrug cationic detergents that bind to anionic lipopolysaccharide molecules of outer cell membrane gm - bacteria causing displacement of calcium and magnesium, which ultimately leads to changes in cell wall permeability, leakage of cellular contents, and subsequent cell death (concentration dependent bactericidal)
