Fengycin--a novel antifungal lipopeptide antibiotic produced by Bacillus subtilis F-29-3.

Fengycin is an antifungal lipopeptide complex produced by Bacillus subtilis strain F-29-3. It inhibits filamentous fungi but is ineffective against yeast and bacteria. The inhibition is antagonized by sterols, phospholipids and oleic acid, whereas two other unsaturated fatty acids increase the antifungal effect. Fengycin consists of two main components differing by one amino acid exchange. Fengycin A is composed of 1 D-Ala, 1 L-Ile, 1 L-Pro, 1 D-allo-Thr, 3 L-Glx, 1 D-Tyr, 1 L-Tyr, 1 D-Orn, whereas in fengycin B the D-Ala is replaced by D-Val. The lipid moiety of both analogs is more variable, as fatty acids have been identified as anteiso-pentadecanoic acid (ai-C15), iso-hexadecanoic acid (i-C16), n-hexadecanoic acid (n-C16), and there is evidence for further saturated and unsaturated residues up to C18.