Diaphorobacter polyhydroxybutyrativorans Qiu et al. 2015 is a later heterotypic synonym of Diaphorobacter nitroreducens Khan and Hiraishi 2003

Comparative analyses of Diaphorobacter polyhydroxybutyrativorans SL-205^T and Diaphorobacter nitroreducens NA10B^T were conducted for clarifying their taxonomic relationship. The sequences of the 16S rRNA gene and nine housekeeping genes of SL-205^T and NA10B^T shared high similarities, above 98.8 %. Whole-genomic comparison between the two strains revealed a digital DNA-DNA hybridization estimate of 85.1 % and an average nucleotide identity of 98.3 % that were well above respective recognized thresholds for bacterial species delineation, strongly indicating that they represent the same genomospecies. The metabolic, physiological and chemotaxonomic features of SL-205^T were also shown to be congruent with those of NA10B^T. Therefore, we conclude that Diaphorobacter polyhydroxybutyrativoransQiu et al. 2015 is a later heterotypic synonym of Diaphorobacter nitroreducens Khan and Hiraishi 2003.

Vibrio coralliirubri sp. nov., a new species isolated from mucus of red coral (Corallium rubrum) collected at Procida island, Italy

Strain Corallo1^T was isolated from mucus of red coral (Corallium rubrum) at Punta Pizzaco (Procida island, Naples, Italy). It was characterised as a Gram-stain negative, motile, rod-shaped bacterium. Strain Corallo1^T was found to show positive responses for cytochrome-c oxidase, catalase, reduction of nitrate and nitrite, β-galactosidase activity and hydrolysis of starch, xylan, peptone, Tween 40, Tween 80 and casein. Strain Corallo1^T was found to be mesophilic, neutrophilic to alkalophilic and slightly halophilic. According to analysis of the almost-complete 16S rRNA gene, strain Corallo1^T is closely related to Vibrio celticus (100% sequence similarity), Vibrio gigantis (100%), Vibrio crassostreae (99.7%), Vibrio artabrorum (99.7%) and Vibrio pomeroyi (99.6%). MLSA of five housekeeping genes (atpA, pyrH, recA, rpoA and rpoD) was performed to refine the phylogenetic relationships of strain Corallo1^T. A draft genome sequence of strain Corallo1^T was obtained. The DNA G+C content of this strain was determined to be 44.5 mol %. The major cellular fatty acids of strain Corallo1^T are C_16:1, n-C_16:0 and C_18:1, and the major isoprenoid ubiquinone is Q8. ANI indexes, in silico estimations of DDH values and wet lab DDH values demonstrated that strain Corallo1^T represents an independent genomospecies. Based on a polyphasic taxonomic characterisation, strain Corallo1^T is concluded to represent a novel species of the genus Vibrio, for which the name Vibrio coralliirubri sp. nov. is proposed. The type strain is Corallo1^T (= DSM 27495^T = CIP 110630^T).