The structure of the lantibiotic lacticin 481 produced by Lactococcus lactis: location of the thioether bridges

[摘要]

The lantibiotic lacticin 481 is a bacteriocin produced by Lactococcus lactis ssp. lactis. This polypeptide contains 27 amino acids, including the unusual residues dehydrobutyrine and the thioether-bridging lanthionine and 3-methyllanthionine. Lacticin 481 belongs to a structurally distinct group of lantibiotics, which also include streptococcin A-FF22, salivaricin A and variacin. Here we report the first complete structure of this type of lantibiotic. The exact location of the thioether bridges in lacticin 481 was determined by a combination of peptide chemistry, mass spectrometry and NMR spectroscopy, showing connections between residues 9 and 14, 11 and 25, and 18 and 26.

[学科分类] 生物化学/生物物理

[关键词] Bacteriocin;Lanthionine-containing polypeptide;Post-translational modification;Cyanogen bromide cleavage;NMR;Mass spectrometry;Ala∗ S;3-methylalanyl moiety of (2S;3S;6R)-3-methyl-lanthionine;AlaS;d-alanyl moiety of meso-lanthionine;sAla;l-alanyl moiety of meso-lanthionine or of (2S;3S;6R)-3-methyllanthionine;1/2/3D;one-/two-/three-dimensional;Dhb;dehydrobutyrine;DMSO;dimethylsulfoxide;DPC;dodecylphosphocholine;FAB;fast-atom bombardment;Hsl;homoserine lactone;MS;mass spectrometry;NOE;nuclear Overhauser enhancement;NOESY;NOE spectroscopy;SA-FF22;streptococcin A-FF22;TOCSY;total correlated spectroscopy