Genomic Insight into Myroides oncorhynchi sp. nov., a New Member of the Myroides Genus, Isolated From the Internal Organ of Rainbow Trout (Oncorhynchus mykiss)

Abstract

The strain M-43(T) was isolated from the Oncorhynchus mykiss from a fish farm in Mugla, Turkey. Pairwise 16S rRNA gene sequence analysis was used to identify strain M-43(T). The strain was a member of the genus Myroides sharing the highest 16S rRNA gene sequence identity levels of 98.7%, 98.3%, and 98.3% with the type strains of M. profundi D25(T), M. odoratimimus subsp. odoratimimus CCUG 39352(T) and M. odoratimimus subsp. xuanwuensis DSM27251(T), respectively. A polyphasic taxonomic approach including whole genome-based analyses was employed to confirm the taxonomic provenance of strain M-43(T) within the genus Myroides. The overall genome relatedness indices (OGRI) for strain M-43(T) compared with its most closely related type strains M. odoratimimus subsp. xuanwuensis DSM 27251(T), M. profundi D25(T), and M. odoratimimus subsp. odoratimimus ATCC BAA-634(T), were calculated as 25.3%, 25.1%, and 25% for digital DNA-DNA hybridization (dDDH), 83.3%, 83.6%, and 83.4% for average nucleotide identity (ANI) analyses, respectively. The OGRI values between strain M-43(T) and its close neighbors confirmed that the strain represents a novel species in the genus Myroides. The DNA G + C content of the strain is 33.7%. The major fatty acids are iso-C-15:0 and summed feature 9 (iso-C-17:1 omega 9c and/or 10-methyl C-16:0). The predominant polar lipids are phosphatidylethanolamine, an amino-lipid and five unidentified lipids. The major respiratory quinone is MK-6. Chemotaxonomic and phylogenomic analyses of this isolate confirmed that the strain represents a novel species for which the name Myroides oncorhynchi sp. nov. is proposed, with M-43(T) as the type strain (JCM 34205(T) = KCTC 82265(T)).