The Sequence of the Enterococcal Cytolysin Imparts Unusual Lanthionine Stereochemistry

The enterococcal cytolysin is a two-component lantibiotic of unknown structure with hemolytic activity that is important for virulence. We prepared cytolysin by co-expression of each precursor peptide with the synthetase CylM in E. coli, and characterized its structure. Surprisingly, cytolysin is the first example of a lantibiotic containing lanthionine and methyllanthionine structures with different stereochemistries in the same peptide, which is determined by the sequence of the substrate peptide.