title: Diversity of Lactobacillus sakei strains investigated by phenotypic and genotypic methods.
abstract: The diversity of 10 strains of Lactobacillus sakei, a commercially important species of lactobacilli, was characterized by studying food isolates. Growth characteristics varied among the strains when examined after growth in a complex medium and a defined medium with either glucose or ribose. A commercial starter culture strain showed the fastest growth rates and high biomass formation on all media, while two of the strains hardly grew on ribose. Based on acidification properties in a meat model, some of the strains had the ability to compete with the indigenous microbiota of the meat batter in addition to being fast acid producers. Carbohydrate-fermentation abilities revealed a relatively wide variation, clustering the strains into two phenotypic groups. The isolates were analyzed using different genetic fingerprinting techniques, demonstrating a distinction between two genetic groups, a grouping consistent with previous studies dealing with L. sakei strains. Comparative genome hybridization (CGH) was introduced for clustering the strains and the same division into two genetic groups was observed. Chromosomal sizes of the strains were estimated by pulsed field gel electrophoresis (PFGE) and were found to vary from 1884 to 2175 kb. The genetic groups did not correlate with the clustering obtained with carbohydrate-fermenting abilities or with chromosomal sizes.
authors.affiliation: Matforsk AS, Nofima Food, Osloveien 1, N-1430 As, Norway.
authors.forename: Anette
authors.initials: A
authors.lastname: McLeod
authors.forename: O Ludvig
authors.initials: OL
authors.lastname: Nyquist
authors.forename: Lars
authors.initials: L
authors.lastname: Snipen
authors.forename: Kristine
authors.initials: K
authors.lastname: Naterstad
authors.forename: Lars
authors.initials: L
authors.lastname: Axelsson
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D055028:Comparative Genomic Hybridization; D005285:Fermentation; D014644:Genetic Variation; D005838:Genotype; D007778:Lactobacillus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D008461:Meat Products / Q000382:microbiology*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D019105:Random Amplified Polymorphic DNA Technique; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D012336:RNA, Ribosomal, 16S