HM17, A NEW POLYENE ANTIFUNGAL ANTIBIOTIC PRODUCED BY A NEW STRAIN OFSPIRILLOSPORA

An antifungal antibiotic (HM17) was obtained from a new isolate classi fied to the genus Spirillospora on the basis of its chemical and morph ological properties. On solid media this antibiotic strongly inhibited the growth of strians of Fusarium oxysporum formae speciales albedini s, Botrytis cinerea, Gaeumaniomyces graminis and several other fungi k nown to be plant and human pathogens. Antifungal activity in culture c ollection strains of Spirillospora has not so far been reported. The u .v. absorption spectrum and physico-chemical characteristics place HM1 7 in the methylpentaene sub-group of polyene macrolides. HM17 is diffe rent from other known methylpentaenes. This is the first report of pol yene production by a Spirillospora.