Abstract
Since the early 1980s, fungi have emerged as a major cause of human disease. Fungal infections are associated with high levels of morbidity and mortality, and are now recognized as an important public health problem. Gram-negative bacterial strains of genus Xenorhabdus are known to form symbiotic associations with soil-dwelling nematodes of the Steinernematidae family. We describe here the discovery of a new antifungal metabolite, cabanillasin, produced by Xenorhabdus cabanillasii. We purified this molecule by cation-exchange chromatography and reverse-phase chromatography. We then determined the chemical structure of cabanillasin by homo- and heteronuclear NMR and MS-MS. Cabanillasin was found to be active against yeasts and filamentous fungi involved in opportunistic infections.