title: A lactococcal expression system for engineered nisins.
abstract: The nisin-producing Lactococcus lactis strain FI5876 has been modified and developed for use as an expression system for engineered nisin variants. Insertional inactivation of the resident nisA gene had a polar effect on downstream genes, including those involved in nisin immunity. However, subsequent chromosomal rearrangements in this region involving a newly discovered insertion element (IS905) generated a strain that was deficient in the nisA gene product but expressed those nisin determinants necessary for prenisin maturation, secretion, and immunity. Complementation of the lesion in the nisA gene by plasmid-encoded nisA genes containing site-specific mutations resulted in the exclusive production of altered nisins containing specific amino acid substitutions.
authors: AFRC Institute of Food Research, Norwich, United Kingdom.
authors: H M
authors: HM
authors: Dodd
authors: N
authors: N
authors: Horn
authors: Z
authors: Z
authors: Hao
authors: M J
authors: MJ
authors: Gasson
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004352:Drug Resistance, Microbial; D005798:Genes, Bacterial / Q000235:genetics*; D005822:Genetic Vectors / Q000235:genetics; D013294:Lactococcus lactis / Q000235:genetics*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009561:Nisin / Q000096:biosynthesis / Q000235:genetics*; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D011994:Recombinant Proteins; D009561:Nisin