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Updated: Aug 17, 2026

Enrichment of Bacterial Lipoproteins and Preparation of N-terminal Lipopeptides for Structural Determination by Mass Spectrometry
Published on: May 21, 2018
The sequence of the enterococcal cytolysin imparts unusual lanthionine stereochemistry
Weixin Tang1, Wilfred A van der Donk
1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
Abstract:
The enterococcal cytolysin is a two-component lantibiotic of unknown structure with hemolytic activity that is important for virulence. We prepared cytolysin by coexpression of each precursor peptide with the synthetase CylM in Escherichia coli and characterized its structure. Unexpectedly, cytolysin is to our knowledge the first example of a lantibiotic containing lanthionine and methyllanthionine structures with different stereochemistries in the same peptide. The stereochemistry is determined by the sequence of the substrate peptide.
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