LCMS/MS-based mining of the peptaibiome: A discovery of new peptaibols

In this study, we employed liquid chromatography–tandem mass spectrometry (LC–MS/MS) to perform chemo-profiling on four fungal species: three Trichoderma species—two strains of Trichoderma asperellum (S3-3 and S3-1) and one Trichoderma longibrachiatum (FS-46)—and one species from the Tolypocladium genus, Tolypocladium inflatum (MTCC-3538). Our analysis identified 78 peptaibols featuring α-aminoisobutyric acid (Aib). Among these, we discovered both cyclic and linear Peptaibols and lipopeptaibols with Aib, ranging in putative molecular weights from 1033.4 to 1953.6 g/mol, corresponding to peptide lengths of 10-20 amino acids. In total, 78 peptaibols, including lipopeptaibols, were identified through LC-MS/MS. Of these, 43 were recognized as new peptaibols based on mass fragmentation patterns and sequence data from the MS/MS analysis. Our findings suggest that LC-MS/MS-based large-scale studies of the peptaibiome will facilitate the discovery of novel peptaibols and provide a valuable reference for understanding the fragmentation patterns of peptaibols, cyclic peptaibols, and lipopeptaibols.