Pristinamycin I, II, Pristinamycine, Pyostacine
This substance is an antibiotic used primarily in the treatment of staphylococcal infections, and to a lesser extent streptococcal infections. It is a streptogramin group antibiotic, similar to virginiamycin, derived from the bacterium Streptomyces pristina spiralis. It is a mixture of two components that have a synergistic antibacterial action. Pristinamycin I is a macrolide, and results in pristinamycin having a similar spectrum of action to erythromycin. Pristinamycin II is a depsipeptide.