Antimicro mech Flashcards
Complex with PBP, _ transpeptidase: _ cross-linking of peptidoglycans: _ cell wall synthesis
Penicillin G; Penicillin V
_ transpeptidase _ _ cell wall synthesis; bulky side group to stop _penicillinases
Oxacillin; Dicloxacillin; Nafcillin (Cloxacillin, Methicillin)
Hydrophilic amino group _ encanced ability to pass through porins _ confers greater Gram negative activity. _ cell wall synthesis
Ampicillin; Amoxicillin
Carboxypenicillin: carboxyl R group allows penetration of porins in G(-) outer memb, _transpeptidase, _cell wall synthesis
Piperacillin; (Ticarcillin; Azlocillin; Carbencillin)
Suicide inhibitor, binds to and inactivates _ _-Lactamase
Zosyn (Piperacillin + Tazobactam); Augmentin (Amoxicillin + Clavulanate)
Bacteriocidal: bind and for complex with PBP, _ transpeptidase: _ cross-linking of peptidoglycans: _ cell wall synthesis; relatively resistant to most (not all) _-Lactamases; Resistance via Transpeptidase mutations, _-Lactamases (esp in G-), Enterococci inherently resistant to cephaosporins
Cefazolin; Cephalexin
Bacteriocidal: bind and for complex with PBP, _ transpeptidase: _ cross-linking of peptidoglycans: _ cell wall synthesis; relatively resistant to most (not all) _-Lactamases; Resistance via Transpeptidase mutations, _-Lactamases (esp in G-), Enterococci inherently resistant to cephaosporins
Cefuroxime (IV); [Cefaclor (PO), Cefuroxime (PO)]
Bacteriocidal: bind and for complex with PBP, _ transpeptidase: _ cross-linking of peptidoglycans: _ cell wall synthesis; relatively resistant to most (not all) _-Lactamases; Resistance via Transpeptidase mutations, _-Lactamases (esp in G-), Enterococci inherently resistant to cephaosporins
Ceftazadime (IV); Cefpodoxime (PO); Ceftriaxone (IV)
Bacteriocidal: bind and for complex with PBP, _ transpeptidase: _ cross-linking of peptidoglycans: _ cell wall synthesis; relatively resistant to most (not all) _-Lactamases; Resistance via Transpeptidase mutations, _-Lactamases (esp in G-), Enterococci inherently resistant to cephaosporins
Cefepime
Complex with PBP, _ transpeptidase: _ cross-linking of peptidoglycans: _ cell wall synthesis; Highly resistant to _-Lactamases; Broadest Spectrum of Activity of all antibacterials
Imipenem (given w/ Cilastin)
_ transpeptidase: _ cell wall synthesis, unique peptidoglycan targets, resistant to _-Lactamases
Aztreonam
Binds rapidly and irreversibly to the D-alanyl-D-alanine muramyl pentapeptide of cell wall precursors _ _ polymerization of peptidoglycans
Vancomycin
Penetrates bacterial cell wall, forming a channel for subsequent leakage of intracellular ions
Daptomycin
Cationic detergents _ Distortion of the membrane lipid structure, _ permeability to polar molecules, via channel
Colistin (Polymyxin E); Polymyxin B
Inhibits _DNA gyrase (Topo II) (supercoiling control), and _Topoisomerase IV (untangling daughter Chr), traps enzyme on DNA
Ciprofloxacin; (Lomefloxaci, Norfloxacin, Oflaxacin)
Inhibits _DNA gyrase (Topo II) (supercoiling control), and _Topoisomerase IV (untangling daughter Chr), traps enzyme on DNA
Levofloxacin
Reductive bioactivation via ferredoxins (in anaerobic bacteria, some protozoa) cytotoxic free radicals react with & damages DNA, protein, or bacterial membranes
Metronidazole
Inhibits _ RNA Polymerase _ _ mRNA transcription; resistance: RNA poly (_) mutation
Rifampin
O2-dependent uptake (anaerobes innately resistant); binds 30S ribosome _ premature termination, mistranslation (bacteriacidal), _ initiation of translation
Gentamicin; Tobramycin; (Neomycin, Streptomycin; Amikacin)
Reversibly binds 30S Ribosome Subunit: block access of _aminoacyl tRNA to its codon (bacteriostatic); imported via energy-dependent active transport lacking in humans
Doxycycline; (Tetracycline, Minocycline, Dmeclocycline, Tigecycline)
Binds 50S Ribosome at A site _blocking _peptidyl transferase _peptide bond synthesis
Clindamycin
Reversibly binds 50S subunit _ _translocation via interference with tRNA release; unrelated -agonist at Motilin R. _ _ GI Motility; Resistance via methylation of tRNA
Azithromycin (Z pack); (Erythromycin, Clarithromycin, Telithromycin)
Binds 50S Ribosome and inhibits _ peptidyl transferase
Linezolid
Binds 50S Ribosome and inhibits _ amino-acyl tRNA interaction with acceptor site
Quinupristin-Dalfopristin
Folic Acid analogue, inhibits DiHydroFolate Reductase _DHFR _(DHF _ THF), _bacterial recycling of folate, _Purines, AA synthesis
Trimethoprim
PABA analogue, competitively _ dihydropteric synthetase _(PABA _DHF) _DNA synthesis, selective (humans lack de novo folate)
Sulfamethoxazole
Prodrug, activated by catalase-peroxidase (KatG) _INH binds enol-ocyl reductase (InhA), _ disrupting _mycolic acid synthesis
Isoniazid (INH)
Prodrug; activated by PZase_ pyrazinoic acid_ inhibits mycobacterial fatty acid synthetase I _ _C16, C24 FA, required for mycolic acid synthesis
Pyrazinamide
Inhibits _ arabinosyl transferases (EmbAB) _ cell wall biosynthesis (arabingalactan)
Ethambutol
Phosphorylated acycloGMP via viral Thymidine Kinase. acycloGTP _ Chain terminator (no 3’OH) & _viral DNA polymerase inhibitor
Acyclovir
Triphosphate form _ Chain terminator & _viral DNA polymerase inhibitor.
Ganciclovir
Inhibits _viral DNA polymerase without need for activation; also _RNA polymerase inhibition
Foscarnet
Prevent viral release from host cells
Oseltamivir; (Zanamivir)
Thymidine analog, tri-phosphorylated by viral enzymes, inhibits HIV’s _reverse transcriptase _chain termination; blocks spread of infection; Resitance via mutations in RT
Zidovudine (AZT, ZDV, Azidothymidine)
Thymidine analog, tri-phosphorylated by viral enzymes, inhibits HIV’s _reverse transcriptase _chain termination; blocks spread of infection; Resitance via mutations in RT
Lamivudine; (Emtricitabine)
High affinity, binds (not at catalytic site), _ inhibits HIV’s RT do not require metabolic activation
Efavirenz; (Nevirapine, Delaviradine; Etravirine)
reversibly inhibits _ HIV protease (cleaves HIV polyproteins [gag, gag-pol] to functional parts) virions are packaged but don’t mature or infect
Ritonavir/Lopinavir; Amprenavir
Prevents_ HCV serine protease cleavage of HCV protein into functional subunits
Boceprevir; Telapravir
Binds first Heptad Repeat (HR1) in _ gp41 envelope glycoprotein, prevents conformational changes require for _fusion to cell membrane
Enfurvitide
Binds CCR5 receptor on macs, T-cells, dendritic cells, preventing HIV from using CCR5 as a co-receptor _entry of CCR5-tropic HIV
Maraviroc
Reversibly inhibits _HIV integrase, preventing viral genome transfer to host cell chromosome
Raltegravir
Binds membrane sterols: _memb. permeability (via pores) _ leakage of K+ and Mg+; selectivity via higher affinity for ergosterol (fungal) vs. cholesterol (mammalian)
Amphotericin B
Binds membrane sterols: _memb. permeability (via pores) _ leakage of K+ and Mg+; selectivity via higher affinity for ergosterol (fungal) vs. cholesterol (mammalian)
Nystatin
inhibits 14--demethylase (a P450 dependent microsomal enzyme): _ lanosterol _ ergosterol. Destabilizes fungal membrane
Clotrimazole; Fluconazole (Voriconazole, Terconazole, Posaconazole, Itraconazole)
Inhibits _ Squalene Epoxidase _ ergosterol synthesis. Destabilizes fungal membrane. Accumulation of squalene is toxic
Terbinafine (Lamisil); Tolnaftate
Inhibits _ glucan synthase complex _ synthesis of _(1,3)-D-Glucan
Caspofungin
Prodrug activated via fungal cytosine deaminase _ 5-fluorouracil, 5-FU + _ _ 5FdUMP _ active inhibitor of _ Thymidylate synthetase
Flucytosine
