1) and 100% 16S rRNA gene sequence identity, Selleck Gefitinib supporting their close affiliation.
The mean sequence identity for the concatenated five protein-coding loci was 98.8% between strains DY05T and 47666-1 and 94.4% between these strains and the relatives V. harveyi, V. campbellii and V. rotiferianus. Discrimination between these species on the basis of phenotypic and 16S rRNA gene analyses is difficult and additional molecular methods such as MLSA have become important tools for correct species delineation and identification (Sawabe et al., 2007; Thompson et al., 2007). Phylogenetic trees generated for concatenated sequences of the five protein-coding loci using NJ, MP and ML methods confirmed the clustering of strains DY05T and 47666-1 (bootstrap values of 100%, 100% and 95%, respectively) and their distinction to close species (Fig. 2, Fig. S1a and b). An extended phylogenetic analysis was performed to detect public database sequences that could potentially belong to the same species as strains DY05T and 47666-1. Using database sequences for the pyrH, topA and mreB loci, Vibrio sp. CAIM 994 clustered with DY05T and 47666-1 in single-gene phylogenetic analyses. Thus, we acquired this strain, isolated from snapper (Lutjanus guttatus) in the northwest coast of Mexico, and determined its 16S rRNA and rpoA gene sequences. Strain CAIM 994 was initially identified as V. rotiferianus, but described as a
possible buy Cabozantinib intermediate strain according to MLSA (Thompson et al., 2007). Phylogenies based on 16S rRNA gene sequences (Fig. 1) and concatenated sequences of five protein-coding loci (Fig. 2) confirmed that CAIM 994, 47666-1 ZD1839 in vitro and DY05T formed a monophyletic group with bootstrap support values
of 99–100%. CAIM 994 shared 99.9% (16S rRNA gene) and 98.3% (five protein-coding loci) gene sequence identities with DY05T and 47666-1. These are greater than the identities shared between CAIM 994 and V. rotiferianus LMG 21460T (99.4% for 16S rRNA gene and 93.2% for five protein-coding loci). Therefore, 16S rRNA gene and MLSA support the notion that CAIM 994 was previously misidentified. Further studies based on phenotypic and genotypic characterization would be required to clarify the relatedness of this and other strains clustering with the Vibrio owensii sp. nov. proposed here. Strains DY05T and 47666-1 showed 76% DNA–DNA hybridization values with each other and 44–55% with V. harveyi LMG 4044T, V. campbellii LMG 11216T and V. rotiferianus LMG 21460T (Table S2). As a DNA–DNA hybridization value of 70% is generally accepted as the limit for species delineation (Wayne et al., 1987), it can be concluded that strains DY05T and 47666-1 belong to a single novel species. The DNA mol% G+C content of DY05T (45.3 mol%) and 47666-1 (45.9 mol%) support their affiliation with Vibrio (Baumann & Schubert, 1983). It can be concluded that strains DY05T and 47666-1 are closely related to V. harveyi, V. campbelli and V.