Structures of trichovirins II, peptaibol antibiotics from the mold Trichoderma viride NRRL 5243

From the culture broth of the mold Trichoderma viride NRRL 5243 a mixture o f polypeptides, named trichovirins (TV), could be isolated and purified by chromatography on XAD-2 adsorber resin and Sephadex LH-20 gel. Chromatograp hy on silica gel using chloroform/methanol 8:2 as eluent provided a mixture of peptides named TV I. Subsequent elution with chloroform/methanol 1:1 yi elded a second group of peptides named TV II. That group could be separated into individual components by repetitive HPLC on an octadecylsilyl and a f luorocarbon stationary phase. The sequences of 12 peptides of TV II could b e determined by electrospray ionization tandem mass spectrometry of isolate d peptides and gas chromatography-mass spectrometry of methanolysates. The N-termini of the 18-mer peptides are acetylated and the C-termini consist o f leucinol. Owing to the presence of alpha-aminoisobutyric acid (Aib) resid ues and the bactericidal and hemolytic activity, the peptides belong to the family of peptaibol antibiotics. Copyright (C) 1999 European Peptide Socie ty and John Wiley & Sons, Ltd.