Phylogenetic study and identification of Vibrio splendidus-related strains based ongyrB gene sequences

Diseases of Aquatic Organisms

Frédérique Le Roux¹  Manolo Gouy¹  Franck Berthe¹  Christophe Lambert¹  Jean Louis Nicolas¹  Mélanie Gay¹ 

关键词: Phylogenetic;    GyrB;    Vibrio splendidus;    Polyphyletic;    Taxonomy;   

DOI  :  10.3354/dao058143

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Different strains related to Vibrio splendidus have been associated with infection of aquatic animals. An epidemiological study of V. splendidus strains associated with Crassostrea gigas mortalities demonstratedgenetic diversity within this group and suggested its polyphyletic nature. Recently 4 species, V. lentus, V. chagasii, V. pomeroyi and V. kanaloae, phenotypically related to V. splendidus, have been described, althoughbiochemical methods do not clearly discriminate species within this group. Here, we propose a polyphasic approach to investigate their taxonomic relationships. Phylogenetic analysis of V. splendidus-related strains was carried out using thenucleotide sequences of 16S ribosomal DNA (16S rDNA) and gyrase B subunit (gyrB) genes. Species delineation based on 16S rDNA-sequencing is limited because of divergence between cistrons, roughly equivalent to divergence between strains. Despite ahigh level of sequence similarity, strains were separated into 2 clades. In the phylogenetic tree constructed on the basis of gyrB gene sequences, strains were separated into 5 independent clusters containing V. splendidus, V. lentus,V. chagasii-type strains and a putative new genomic species. This phylogenetic grouping was almost congruent with that based on DNA-DNA hybridisation analysis. V. pomeroyi, V. kanaloae and V. tasmaniensis-type strainsclustered together in a fifth clade. The gyrB gene-sequencing approach is discussed as an alternative for investigating the taxonomy of Vibrio species.

【 授权许可】

Unknown