At this point, four enzymes use acetyl-CoA to add a methyl group to position 12 on the macromolecule.
[4] Finally, a D-proline residue is added to the chain, followed by hydroxylation and dehydration to form dehydroproline, which is thought to occur through a reverse Michael-type reaction.
Streptogramin A first binds to the peptidyl transferase domain of the 50s ribosomal subunit, preventing the early events of elongation.
When both streptogramins are bound to the ribosome, they form an extremely stable ternary complex.
This intravenously injected drug is used to treat patients with bacteremia caused by vancomycin-resistant Enterococcus faecium.
The three major mechanisms of resistance include active efflux, covalent target modification and antibiotic inactivation enzymes.