The antifungal activity of mupirocin

The antibacterial agent mupirocin (pseudomonic acid A) is used as a topical agent in the treatment of superficial infections by Gram-positive bacteria , particularly Staphylococcus aureus, However, we demonstrate here that the compound also inhibits the growth of a number of pathogenic fungi in vitro , including a range of dermatophytes and Pityrosporum spp. it inhibited the incorporation of amino acids and precursors of RNA, but not that of acetat e, by Trichophyton mentagrophytes. It also inhibited the isoleucyl-tRNA syn thetase from Candida albicans, indicating a mechanism of action similar to that in bacteria. When administered topically, mupirocin was efficacious in a T, mentagrophytes ringworm model in guinea pigs, These results suggest t hat mupirocin could have clinical utility for superficial infections caused by dermatophytes.