Structural characterization of lipopeptide methyl esters produced by Bacillus licheniformis HSN 221.

Lipopeptides and their analogues are of increasing interest due to their amphiphilic structures and potential applications in various fields. Three purified lipopeptides analogues were obtained at the same time after two-step column-chromatographic purification from cell-free broth cultivated by Bacillus licheniformis HSN 221. Analysis by ESI-MS, GC/MS, HPLC, and Q-TOF MS/MS revealed their primary structures as anteiso-C(15)- and iso-C(15)-beta-hydroxy fatty acid-Gln-Leu-Leu-Val-MeAsp-Leu-Ile, anteiso-C(15)- and iso-C(15)-beta-hydroxy fatty acid-MeGlu-Leu-Leu-Val-Asp-Leu-Ile and iso-C(16)-beta-hydroxy fatty acid-Glu-Leu-Leu-Val-MeAsp-Leu-Ile, respectively. The production of two surfactin monomethyl esters and one lichenysin monomethyl ester directly from microorganisms is helpful to understand the variants of metabolites.