Photobacterium galatheae sp. nov., a bioactive bacterium isolated from a mussel in the Solomon Sea

A novel, Gram-negative marine bacterium, S2753^T, was isolated from a mussel of the Solomon Sea, Solomon Islands. Analysis of the 16S rRNA gene sequence and whole genome sequence data placed strain S2753^T in the genus Photobacterium with the closest relative being Photobacterium halotolerans DSM 18316^T (97.7 % 16S rRNA gene similarity). Strain S2753^T was able to grow from 15 to 40 °C and in NaCl concentrations of 0.5 to 9 % (w/v). The predominant fatty acids were 16 : 1ω7c/16 : 1ω6c (27.9 %), 16 : 0 (22.1 %) and 18 : 1ω7c/8 : 1ω6c (21.4 %). The genomic DNA G+C mol content was 49.5 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic differences, strain S2753^T is considered to represent a novel species of the genus Photobacterium. Furthermore, whole genome sequence analysis comparing S2753^T and type-strains of closely related species of the genus Photobacterium also demonstrated that the strain is genomically distinct enough to be considered a novel species. The name Photobacterium galatheae is proposed and the type-strain is S2753^T( = LMG 2889^4T= DSM 100496^T).