title: Complete covalent structure of nisin Q, new natural nisin variant, containing post-translationally modified amino acids.
abstract: The third member of the nisin variant, nisin Q, produced by Lactococcus lactis 61-14, is a ribosomally-synthesized antimicrobial peptide, the so-called lantibiotic containing post-translationally modified amino acids such as lanthionine and dehydroalanine. Here, we determined the complete covalent structure of nisin Q, consisting of 34 amino acids, by two-dimensional (1)H nuclear magnetic resonance (NMR) spectroscopy. Sequential assignment of nisin Q containing the unusual amino acids was performed by total correlation spectroscopy (TOCSY) and nuclear Overhauser enhancement spectroscopy (NOESY). The observed long range nuclear Overhauser effect (NOE) in nisin Q indicated assignment of all five sets of lanthionines that intramolecularly bridge residues 3-7, 8-11, 13-19, 23-26, and 25-28. Consequently, the covalent structure of nisin Q was determined to hold the same thioether linkage formation as the other two nisins, but to harbor the four amino acid substitutions, in contrast with nisin A.
authors.affiliation: Department of Bioscience and Biotechnology, Division of Microbial Science and Technology, Faculty of Agriculture, Laboratory of Microbial Technology, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Fukao
authors.forename: Takayuki
authors.initials: T
authors.lastname: Obita
authors.forename: Fuminori
authors.initials: F
authors.lastname: Yoneyama
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kohda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Zendo
authors.forename: Jiro
authors.initials: J
authors.lastname: Nakayama
authors.forename: Kenji
authors.initials: K
authors.lastname: Sonomoto
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives; D019943:Amino Acid Substitution; D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009561:Nisin / Q000096:biosynthesis / Q000737:chemistry*; D011499:Protein Processing, Post-Translational; D013440:Sulfides
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D013440:Sulfides; D009561:Nisin; C015102:dehydroalanine; C001520:lanthionine; D000409:Alanine