Ala(0)-actagardine, a New Lantibiotic from Cultures of Actinoplanes liguriae ATCC 31048

抄録

The actagardine-producing strain Actinoplanes liguriae ATCC 31048, forms an additional lantibiotic when it is cultured on mannitol and soya meal. The new compound, Ala(O)-actagardine (1), has been isolated by solid-phase extraction followed by a two-step chromatographic separation. The molecular formula of 1 is C₈₄H₁₂₉N₂₁O₂₅S₄ Its chemical structure was determined by 2D-NMR analysis and was further confirmed by an amino acid analysis, Edman degradation, and partial synthesis from actagardine. 1 exhibits a slightly higher biological activity than the parent compound actagardine. The synthetic analogs Lys(0)-actagardine (2) and Ile(0)-actagardine (3) demonstrate also antibacterial activities and emphasize the importance of the N-terminus for further derivatization.