title: Incorporation of tryptophan analogues into the lantibiotic nisin.
abstract: Lantibiotics are posttranslationally modified peptides with efficient inhibitory activity against various Gram-positive bacteria. In addition to the original modifications, incorporation of non-canonical amino acids can render new properties and functions to lantibiotics. Nisin is the most studied lantibiotic and contains no tryptophan residues. In this study, a system was constructed to incorporate tryptophan analogues into nisin, which included the modification machinery (NisBTC) and the overexpression of tryptophanyl-tRNA synthetase (TrpRS). Tryptophan and three different tryptophan analogues (5-fluoroTrp (5FW), 5-hydroxyTrp (5HW) and 5-methylTrp (5MeW)) were successfully incorporated at four different positions of nisin (I1W, I4W, M17W and V32W). The incorporation efficiency of tryptophan analogues into mutants I1W, M17W and V32W was over 97 %, while the mutant I4W showed relatively low incorporation efficiency (69-93 %). The variants with 5FW showed relatively higher production yield, while 5MeW-containing variants showed the lowest yield. The dehydration efficiency of serines or threonines was affected by the tryptophan mutants of I4W and V32W. The affinity of the peptides for the cation-ion exchange and reverse phase chromatography columns was significantly reduced when 5HW was incorporated. The antimicrobial activity of IIW and its 5FW analogue both decreased two times compared to that of nisin, while that of its 5HW analogue decreased four times. The 5FW analogue of I4W also showed two times decreased activity than nisin. However, the mutant M17W and its 5HW analogue both showed 32 times reduced activity relative to that of nisin.
authors.affiliation: Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Laboratory of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Shao
authors.affiliation: Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
authors.forename: Auke J
authors.initials: AJ
authors.lastname: van Heel
authors.affiliation: Department of Pediatrics, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713GZ, Groningen, The Netherlands.|Mass Spectrometry Core Facility, Department of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands.
authors.forename: Marcel P
authors.initials: MP
authors.lastname: de Vries
authors.affiliation: Laboratory of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
authors.forename: Jaap
authors.initials: J
authors.lastname: Broos
authors.affiliation: Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands. o.p.kuipers@rug.nl.
authors.forename: Oscar P
authors.identifier: http://orcid.org/0000-0001-5596-7735
authors.initials: OP
authors.lastname: Kuipers
mesh_terms: D001430:Bacteriocins / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D013294:Lactococcus lactis / Q000187:drug effects; D015394:Molecular Structure; D009561:Nisin / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology*; D014364:Tryptophan / Q000031:analogs & derivatives / Q000235:genetics / Q000494:pharmacology*
chemical_list: D001430:Bacteriocins; D009561:Nisin; D014364:Tryptophan
keywords: Biosynthetic incorporation; Lantibiotics; Nisin; Non-canonical amino acids; Tryptophan analogues