Inhibitors of Bacterial Protein Synthesis Flashcards
Gentamicin, Neomycin, Amikacin,
Tobramycin, Streptomycin
Aminoglycosides
Mechanism: inhibit formation of initiation
complex and cause misreading of mRNA. Also
block translocation. Require O2 for uptake;
therefore ineffective against anaerobes.
targets: Gram - rod
Resistance: Transferase enzyme inactivates drug by acetylation, phosphorylation or adenylation
Aminoglycosides Side Effect
nephrotoxicity, neuromuscular blockade, ototoxicity and teratogen
Tetracycline, doxycycline, minocycline
Mechanism: bind to 30S and prevent attachment of aminoacyl-tRNA. Doxycycline is fecally eliminated and can be used in patients with renal failure. Do not take with milk (Ca2+), antacids (Ca2+ or Mg2+), or iron-containing preparations because divalent cations inhibit its absorption in the gut.
Targets: Borrelia Burgdorfei, Mycoplasma Pneumonia, Rickettsia, Chlamydia
Resistance: Decrease uptake or increase efflux by plasma pumps
Tetracyclines Side Effects
GI distress, discoloratin of teeth, inhibition of bone growth in children, photosensitivity
Chloramphenicol
Mechanism: Blocks peptidyltransferase at 50S ribosomal subunit (stops peptide bond formation)
Targets: bacterial meningitis, Rickettsia, Salmonella Typhi, B. fragilis
Resistance: Acetyltransferase
Side Effect: dose dependent anemia; aplastic anemia, grey baby syndrome (low glucuronosyl transferase)
Azithromycin, clarithromycin, erythromycin.
Macrolides
Mechanism: Inhibit protein synthesis by blocking translocation. bind to the 23S rRNA of the
50S ribosomal subunit
Targets: Gram + cocci (not MRSA), Atypical organisms, legionella, Campylobacter, Mycobacterium, H. pylori
Resistance: Formation of methyltransferase, alters 50S
Side Effects: GI distress, ototoxicity
Clindamycin
Same as macrolides
Targets: gram + cocci, anaerobes
Side Effect: pseudomembranous colitis
Linezolid
Mechanism: formation of the initiation complex in bacterial translation system
Targets: VRSA, VRE
Side Effects: bone marrow suppression
