Shewanella oncorhynchi sp. nov., a novel member of the genus Shewanella , isolated from Rainbow Trout ( Oncorhynchus mykiss ).

A strain, S-1 ^T was isolated from rainbow trout ( Oncorhynchus mykiss ) exhibiting clinical symptoms of lens atrophy, inappetence, visual impairment and growth retardation. The strain was identified as representing a member of the genus Shewanella on the basis of the results of 16S rRNA gene sequence analysis. The neighbor-joining phylogenetic tree based on 16S rRNA gene sequences indicated that S-1 ^T clustered with Shewanella putrefaciens JCM 20190 ^T , Shewanella profunda DSM 15900 ^T , and Shewanella hafniensis P010 ^T , sharing 99.3, 98.8 and 87.7% 16S rRNA gene similarities, respectively. A polyphasic taxonomic approach including phenotypic, chemotaxonomic, and genomic characterization was employed to ascertain the taxonomic position of S-1 ^T within the genus Shewanella . The overall genome relatedness indices (OGRI) for S-1 ^T compared with the most closely related type strains S. hafniensis ATCC BAA-1207 ^T , Shewanella baltica NCTC 10735 ^T , S. putrefaciens ATCC 8071 ^T and S. profunda DSM 15900 ^T were calculated as 40.8, 40.1, 28.5 and 27.3% for digital DNA-DNA hybridization (dDDH), and 91.6, 91.0, 86.3 and 85.1% for average nucleotide identity (ANI), respectively. OGRI values between S-1 ^T and its close neighbours confirmed that the strain represents a novel species in the genus Shewanella .The DNA G+C content of the strain is 45.2%. Major fatty acids were C _{17 : 1} ω8 c , C _{15 : 0} iso, and summed feature 3 (C _{16 : 1} ω6 c and/or C _{16 : 1} ω7 c ). The predominant polar lipids were phosphatidylethanolamine, phospholipid, amino-phospholipid and unidentified lipids. The major respiratory quinones were ubiquinone-8, ubiquinone-7 and menaquinone-7. Chemotaxonomic and phylogenomic analyses of this isolate confirmed that the strain represents a novel species for which the name Shewanella oncorhynchi sp. nov. is proposed, with S-1 ^T as the type strain (JCM 34183 ^T = KCTC 82249 ^T ).