title: Nucleotide sequence and analysis of pBL1, a bacteriocin-producing plasmid from Lactococcus lactis IPLA 972.
abstract: The complete sequence of the 10.9-kbp bacteriocinogenic plasmid pBL1 from Lactococcus lactis subsp. lactis IPLA 972 has been determined. Thirteen ORFs were encountered, of which 5 were incomplete. pBL1 proved to be a narrow-host-range plasmid which replicates neither in Bacilus subtilis nor in Lactobacillus spp. The structural organization of the pBL1 replication region was highly similar to other well-known theta-replicating plasmids of lactococci, at both the untranslated (the replication origin) and the translated (repB and orfX) sequences. As in other plasmids, the product of orfX was not necessary for plasmid replication. However, it was shown to be involved in plasmid stability. Three genes organized in an operon-like structure encompassed, most likely, the bacteriocin-encoding region. Upstream of the origin of replication a nicking site (oriT) was found. This oriT sequence proved to be functional by mobilization of plasmids wearing it. One complete and several partial IS elements were identified on pBL1.
authors.affiliation: Instituto de Productos Lácteos de Asturias (CSIC), Carretera de Infiesto s/n, Villaviciosa, Asturias, 33300-, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Sánchez
authors.forename: A
authors.initials: A
authors.lastname: Hernández de Rojas
authors.forename: B
authors.initials: B
authors.lastname: Martínez
authors.forename: M E
authors.initials: ME
authors.lastname: Argüelles
authors.forename: J E
authors.initials: JE
authors.lastname: Suárez
authors.forename: A
authors.initials: A
authors.lastname: Rodríguez
authors.forename: B
authors.initials: B
authors.lastname: Mayo
mesh_terms: D000595:Amino Acid Sequence; D001430:Bacteriocins / Q000096:biosynthesis / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics*; D013294:Lactococcus lactis / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D001430:Bacteriocins; D004269:DNA, Bacterial