The streptogramin antibiotics: update on their mechanism of action.

摘要: Antibiotics of the streptogramin class are an association two types chemically different compounds, group A molecules and B molecules, acting in synergy. The combination these generally inhibits bacterial growth at a lower concentration than does either or molecule alone is often bactericidal against strains bacteria for which each type only bacteriostatic. semisynthetic quinupristin/dalfopristin (RP 59500), first water-soluble member this class, under development treatment severe infections caused by methicillin-resistant Staphylococcus aureus, epidermidis, penicillin-resistant Streptococcus pneumoniae, glycopeptide-resistant Enterococcus faecium, other organisms. streptogramins block translation mRNA into protein. Both bind to peptidyl-transferase domain ribosome. stimulates dissociation peptidyl-tRNA from ribosome may interfere with passage completed polypeptide away centre. elongation chain preventing both binding aminoacyl-tRNA ribosomal site formation peptide bond. When used combination, alters conformation such that affinity increased. This accounts, part entirely, observed synergy unaffected modifications conferring resistance macrolides, lincosamides, alone.