title: Characterization of the amylovorin locus of Lactobacillus amylovorus DCE 471, producer of a bacteriocin active against Pseudomonas aeruginosa, in combination with colistin and pyocins.
abstract: Lactobacillus amylovorus DCE 471 produces amylovorin L, a bacteriocin with an antibacterial activity against some strains of the Lactobacillus lineage. Based on the sequence of one active peptide, a gene encoding active amylovorin L was cloned and sequenced. Genome walking allowed us to sequence a larger fragment of 7577 bp of genomic DNA, with 12 predicted ORFs. The previously characterized amylovorin L peptide-encoding gene is preceded by another gene encoding a small polypeptide with a typical bacteriocin-processing double-glycine site, suggesting that amylovorin L is a two-component class IIb bacteriocin (amylovorin Lalpha/beta). Lalpha and Lbeta show the highest similarity to gassericin T from Lactobacillus gasseri SBT2055 and BlpN from Streptococcus pneumoniae R6, respectively, and to LafA and LafX, which form the lactacin F bacteriocin of Lactobacillus johnsonii NCC 533. As for other lactic acid bacteria bacteriocins, amylovorin L showed no activity against the Gram-negative opportunistic pathogen Pseudomonas aeruginosa on its own, but showed synergistic inhibitory activity when used in combination with the peptide antibiotic colistin, and, remarkably, with the P. aeruginosa soluble bacteriocins, pyocins S1 and S2.
authors.affiliation: Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Department of Applied Biological Sciences and Engineering, Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Maria R Foulquie
authors.initials: MR
authors.lastname: Moreno
authors.forename: Barbara
authors.initials: B
authors.lastname: Baert
authors.forename: Sarah
authors.initials: S
authors.lastname: Denayer
authors.forename: Pierre
authors.initials: P
authors.lastname: Cornelis
authors.forename: Luc
authors.initials: L
authors.lastname: De Vuyst
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000494:pharmacology*; D001430:Bacteriocins / Q000096:biosynthesis* / Q000494:pharmacology*; D016386:Chromosome Walking; D003001:Cloning, Molecular; D003091:Colistin / Q000494:pharmacology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004357:Drug Synergism; D023061:Gene Order; D007779:Lactobacillus acidophilus / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D011709:Pyocins / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D004269:DNA, Bacterial; D011709:Pyocins; C402567:amylovorin L471; D003091:Colistin