L13:protein synthesis inhibitors Flashcards
what are the 2 major classes of protein synthesis inhibitors ?
macrolides and aminoglycosides
macrolides include:
erythromycin ,clarithromycin , roxithromycin , azithromycin
what is the role of macrolides?
used as alternatives to penicillin in patients allergic to beta-lactam antibiotics
how do macrolides inhibit protein synthesis of bacteria?
they bind irreversibly to the 50s subunit of ribosomes , inhibiting the translocation steps of proteins synthesis from occurring
are macrolides bacteriostatic or bactericidal ?
bacteriostatic but in high concentrations can be bactericidal
macrolides mostly affect gram positive bacteria and just a few gram negative ones , just like penicillin
:D
What are some of the adverse effects of macrolides?
abdominal cramps , nausea / vomitting , diarrhea , stamositis , cholestatic jaundice , elevated liver enzymes
which group of people should avoid macrolides if possible ?
people with hepatitis
chemoprophalaxis using macrolides :
500mg 1 hour before procedure
when are aminoglycosides uses>?
to treat serious aerobic gram negative (-ve) bacilli infection
bacterial endocarditis
TB
punmonia
eye infection
skin infection
are aminoglycosides bacteriostatic or bactericidal ?
bactericidal
in which medium are aminoglycosides most effective?
alkaline medium
how do aminoglycosides inhibit bacterial protein synthesis ?
binding to 30s subunit of ribosomes
what are the adverse effects of aminoglycosides ?
-ototoxicity
-nephrotoxicity
-neuromuscular paralysis
(amikacin and kanamycin cause auditory dysfunction
whats the spectrum of activity of macrolides and aminoglycosides?
macrolides : wider spectrum , especially newer variants that aren’t erythromycin ).
aminoglycosides have a narrow spectrum of action
