Linezolid is a synthetic oxazolidinone antibiotic active against a wide range of Gram-positive bacteria, including resistant strains of several species, such as MRSA, penicillin-resistant pneumococci, vancomycin-resistant enterococci, many different streptococci, various anaerobic bacteria, and several mycobacteria. Linezolid inhibits protein synthesis by binding to domain V of the 23S ribosomal RNA of the 50S subunit of bacterial ribosomes.