Transposon mutagenesis in Bifidobacterium breve: construction and characterization of a Tn5 transposon mutant library for Bifidobacterium breve UCC2003

• Published in: PloS one Vol. 8; no. 5; p. e64699
• Main Authors: Ruiz, Lorena, Motherway, Mary O'Connell, Lanigan, Noreen, van Sinderen, Douwe
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 30.05.2013; Public Library of Science (PLoS)
• Subjects: Bifidobacterium - drug effects; Bifidobacterium - genetics; Bifidobacterium - growth & development; Biology; Carbohydrates - pharmacology; Carbon - pharmacology; Commensals; D-Galactose; Defects; DNA Transposable Elements - genetics; E coli; Galactose; Gene Library; Genes; Genetic engineering; Genomes; Genomics; Insertion; Lactose; Libraries; Medical screening; Metabolic disorders; Metabolism; Molecular biology; Molecular modelling; Mutagenesis; Mutagenesis, Insertional - drug effects; Mutants; Mutation; Mutation - drug effects; Occupational health; Phenotype; Probiotics; Transposon mutagenesis; Transposons
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0064699

Bifidobacteria are claimed to contribute positively to human health through a range of beneficial or probiotic activities, including amelioration of gastrointestinal and metabolic disorders, and therefore this particular group of gastrointestinal commensals has enjoyed increasing industrial and scientific attention in recent years. However, the molecular mechanisms underlying these probiotic mechanisms are still largely unknown, mainly due to the fact that molecular tools for bifidobacteria are rather poorly developed, with many strains lacking genetic accessibility. In this work, we describe the generation of transposon insertion mutants in two bifidobacterial strains, B. breve UCC2003 and B. breve NCFB2258. We also report the creation of the first transposon mutant library in a bifidobacterial strain, employing B. breve UCC2003 and a Tn5-based transposome strategy. The library was found to be composed of clones containing single transposon insertions which appear to be randomly distributed along the genome. The usefulness of the library to perform phenotypic screenings was confirmed through identification and analysis of mutants defective in D-galactose, D-lactose or pullulan utilization abilities.