Autor: |
Miller WG; Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, USA., Lopes BS; School of Health and Life Sciences, Teesside University, Middlesbrough, UK.; National Horizons Centre, Teesside University, Darlington, UK., Ramjee M; Wolfson Wohl Cancer Research Centre, Glasgow. The University of Glasgow, Glasgow, UK., Jay-Russell MT; Western Center for Food Safety, University of California, Davis, CA, USA., Chapman MH; Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, USA., Williams TG; Bioproducts Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, USA., Wood DF; Bioproducts Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, USA., Gruntar I; University of Ljubljana, Veterinary Faculty, Institute of Microbiology and Parasitology, Ljubljana, Slovenia., Papić B; University of Ljubljana, Veterinary Faculty, Institute of Microbiology and Parasitology, Ljubljana, Slovenia., Forbes KJ; School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK. |
Abstrakt: |
In a previous study characterizing Campylobacter strains deficient in selenium metabolism, 50 strains were found to be similar to, but distinct from, the selenonegative species Campylobacter lanienae . Initial characterization based on multilocus sequence typing and the phylogeny of a set of 20 core genes determined that these strains form three putative taxa within the selenonegative cluster. A polyphasic study was undertaken here to further clarify their taxonomic position within the genus. The 50 selenonegative strains underwent phylogenetic analyses based on the sequences of the 16S rRNA gene and an expanded set of 330 core genes. Standard phenotypic testing was also performed. All strains were microaerobic and anaerobic, Gram-negative, spiral or curved cells with some displaying coccoid morphologies. Strains were motile, oxidase, catalase, and alkaline phosphatase positive, urease negative, and reduced nitrate. Strains within each clade had unique phenotypic profiles that distinguished them from other members of the genus. Core genome phylogeny clearly placed the 50 strains into three clades. Pairwise average nucleotide identity and digital DNA-DNA hybridization values were all below the recommended cut-offs for species delineation with respect to C. lanienae and other related Campylobacter species. The data presented here clearly show that these strains represent three novel species within the genus, for which the names Campylobacter devanensis sp. nov. (type strain RM3662 T =LMG 33097 T =NCTC 15074 T ), Campylobacter porcelli sp. nov. (type strain RM6137 T =LMG 33098 T =CCUG 77054 T =NCTC 15075 T ) and Campylobacter vicugnae sp. nov. (type strain RM12175 T =LMG 33099 T =CCUG 77055 T =NCTC 15076 T ) are proposed. |