Chapter 3 Flashcards
(51 cards)
11 natural antibiotics
Penicillin G = kills grams
cephalosporin C = kills grams
carbapenems = thienamycin
monobactams = aztreonam kills G - only
lipopeptides = daptomycin
aminoglycoside = streptomycin = kills Grams and mycobacteria
glycopeptides = vancomycin = kills G +
macrolide, azalide, ketolide = clarithromycin = kills G +, chlamydia, ricketsii, mycoplasma
lincomycin
tetracycline = doxycycline = kills grams, chlamydia, rickettsia, mycoplasma
streptogramins
5 synthetic antibacterials
floroquniolones = cipro = true broad spectrum
nitroimidazole = metronidazole
oxazolidinones = linezolid
trimethoprim
sulfonaminde = SMX = kills Grams
penicillin
mech
location
Resistance
“Cidal”
inhibit cell wall synthesis (peptidoglycan)
NOT CELL MEMBRANE
bind to and inactivate penicillin binding proteins, which are enzymes involved in peptidoglycan synthesis
Resistance: bugs modified PBPs, formed beta lactamases, and decreased uptake of drug via porin in OM
cephalosporin
mech
location
resistance
“Cidal”
inhibit cell wall synthesis (peptidoglycan)
NOT CELL MEMBRANE
bind to and inactivate penicillin binding proteins, which are enzymes involved in peptidoglycan synthesis
Resistance: bugs modified PBPs, formed beta lactamases, and decreased uptake of drug via porin in OM
carbapenems
mech
location
resistance
“Cidal”
inhibit cell wall synthesis (peptidoglycan)
NOT CELL MEMBRANE
bind to and inactivate penicillin binding proteins, which are enzymes involved in peptidoglycan synthesis
Resistance: bugs modified PBPs, formed beta lactamases, and decreased uptake of drug via porin in OM
monobactams
mech
location
Resistance
“Cidal”
inhibit cell wall synthesis (peptidoglycan)
NOT CELL MEMBRANE
bind to and inactivate penicillin binding proteins, which are enzymes involved in peptidoglycan synthesis
Resistance: bugs modified PBPs, formed beta lactamases, and decreased uptake of drug via porin in OM
glycopeptides
mech
location
Resistance
“Cidal”
inhibit cell wall synthesis (peptidoglycan)
hinders formation of interpeptide bridges required for cross-linking to synthesize peptidoglycan layer by binding to side chain terminus
Resistance: bugs changed peptidoglycan
bacitracin
mech
location
“Cidal”
inhibit cell wall synthesis (peptidoglycan)
forms complex with and prevents regeneration of a lipid carrier that is needed to make cell wall
aminoglycoside
mech
location
Resistance
inhibit protein synthesis
Bind 30S ribosomal subunit which impairs translation of mRNA into protein by causing misreading
anaerobes are resistant
Resistance: bugs changed ribosomal protein, formed inactivating enzymes against the transferases
“lides” and chloramphenicol
mech
location
Resistance
ie: erythromycin
“static”
inhibit protein synthesis
Bind 50S ribosomal subunit which causes blockage of translation of mRNA into protein
Resistance: altered ribosomal RNA methylation, and active efflux due to membrane transport system
Resistance for chloramphenicol: produced inactivating enzyme acetyltransferase and decreased uptake of antibiotic secondary to changes in OM porins
oxazolidinones (synthetic), lincosamides, and streptogamins
mech
location
“static”
inhibit protein synthesis
Bind 50S ribosomal subunit which causes blockage of translation of mRNA into protein
fluoroquinolones (synthetic)
mech
location
Resistance
“cidal”
inhibit nucleic acid synthesis/fxn
interfere with DNA replication by inhibiting DNA gyrase
Resistance: change in DNA gyrase, decreased uptake of antibiotic secondary to changes in OM porins, and active efflux due to membrane transport system
trimethoprim (synthetic) sulfonamides (synthetic) mech location Resistance
antifolates AKA bactrim
Trimethoprim: block nucleic acid precursor by inhibiting dihydrofolate reductase
Sulfonamides: block nucleic acid precursor by inhibiting tetrahydropteroic acid synthase
Resistance: New drug insensitive dihydrofolate synthetase (dihydropteroate synthase) or excess production of normal enzyme and Decreased uptake secondary to changes in outer membrane protein channels (Porins) of gram negative organisms
**enterococci are resistant
polymyxcin and lipopeptides
mech
location
“cidal”
disruption of cell membrane fxn
isoniazid
mech
location
“cidal”
inhibit cell wall synthesis
inhibit syn of mycolic acid of mycobacterial cell wall
tetracycline
mech
location
Resistance
“static”
inhibit protein synth
Bind 30S ribosomal subunit which impairs translation of mRNA into protein by blocking binding of aminoacyltRNA
Resistance: alter ribosomal protection, active efflux due to membrane transport system, and Decreased uptake secondary to changes in outer membrane protein channels (Porins) of gram negative organisms
nitroimidazole (synthetic)
mech
location
“cidal”
inhibit nucleic acid synthesis/fxn
microbial enzyme liberates toxin that breaks strands, causes loss of helical conformation, and impairs DNA template fxn
rifampin
mech
location
Resistance
“cidal”
inhibit nucleic acid synthesis/fxn
inhibit RNA polymerase
Resistance: change in RNA polymerase
outer membrane consists of:
targets:
LPS, phospholipid, lipoprotein, proteins
G ( - ) bacteria
targets:
passive diffusion across
porin channel
LPS, virulence
amphoteracin B works on
Effective against all fungi but only appropriate for:
aspergillosis - mold on inside of body
crytococcosis - yeast on inside of body
nystatin works on
Effective against all fungi but only appropriate for:
cadidasis albicans - yeast on surface of body
fluconazole works on
All fungi because it is a triazole, but mainly focuses on:
candida ablicans
crytococcosis
this drug has CYP based ADR
ketoconazole works on
dermatophytosis bastomycosis coccidiomycosis candida albicans this drug has CYP based ADR
terbinafine works on
dermatophytosis
