Lantibiotics are a class of polycyclic peptide antibiotics that contain the characteristic thioether amino acids lanthionine or , as well as the unsaturated amino acids dehydroalanine, and 2-aminoisobutyric acid. They belong to ribosomally synthesized and post-translationally modified peptides. Lanthionine is composed of two alanine residues that are crosslinked on their β-carbon atoms by a thioether (monosulfide) linkage. Lantibiotics are well studied because of the commercial use of these bacteria in the food industry for making dairy products such as cheese.