Mupirocin reversibly binds to bacterial isoleucyl-tRNA synthetase, an enzyme which promotes the conversion of isoleucine and tRNA to isoleucyl-tRNA. Prevention of this enzymes from functioning properly results in the inhibition of bacterial protein and RNA synthesis.
Mupirocin, an antibiotic produced from Pseudomonas fluorescens, is structurally unrelated to any other topical or systemic antibiotics. Mupirocin is used to treat infection caused by Staphylococcus aureus and beta-hemolytic streptococci including Streptococcus pyogenes. This antibiotic has little, if any, potential for cross-resistance with other antibiotics.
Hepatic. Following intravenous or oral administration, mupirocin is rapidly metabolized. The principal metabolite is monic acid, which has no antibacterial activity.