title: Characterization of minimal bacteriocin operon from Prevotella nigrescens ATCC 25261.
abstract: OBJECTIVE
  To characterize a minimal bacteriocin operon of Prevotella nigrescens ATCC 25261.
  
  
  RESULTS
  A genomic DNA library of Pr. nigrescens ATCC 25261 was constructed and screened for bacteriocin production by an agar overlay assay. Sequence analysis of the bacteriocin-producing recombinant plasmid, pGP2, has shown that the insert DNA consists of 4868 base pairs, termed nig locus. There is a cluster of four genes within the nig locus, respectively designated nigA, B, C and D. Deleting 160 nucleotides at the 3'-end of nigAB resulted in loss of bacteriocin production, indicating that nigAB may belong to a bacteriocin operon. nigA is thought to be the bacteriocin gene, while nigB may encode an immunity protein. Escherichia coli containing pGP2 expressed the bacteriocin, which is similar in size, antimicrobial activity, and biochemical properties to that purified from Pr. nigrescens ATCC 25261.
  
  
  CONCLUSIONS
  nig Locus is a chromosomal fragment of Pr. nigrescens ATCC 25261, consisting of 4868 base pairs, and has been proved to be important for bacteriocin production.
  
  
  CONCLUSIONS
  This is the first report of the successful cloning and expression of the bacteriocin from Pr. nigrescens ATCC 25261 into E. coli. This will facilitate the construction of bacteriocin analogues and permit investigation of their structure/function relationships.
authors.affiliation: Department of Stomatology, Faculty of Dentistry, Prince of Songkla University, Songkhla, Thailand. jasadee.k@psu.ac.th
authors.forename: J
authors.initials: J
authors.lastname: Kaewsrichan
authors.forename: C W I
authors.initials: CW
authors.lastname: Douglas
authors.forename: R
authors.initials: R
authors.lastname: Teanpaisan
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001430:Bacteriocins / Q000096:biosynthesis*; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015698:Genomic Library; D008969:Molecular Sequence Data; D009876:Operon; D045242:Prevotella nigrescens / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D001430:Bacteriocins