Alterinioella nitratireducens gen. nov., sp. nov., Isolated from Seawater in the West Pacific Ocean.

A novel Gram-negative, nonspore forming, nonmotile, and short-rod-shaped aerobic bacterium, designated DY48A3-103T, was isolated from a seawater sample collected from the West Pacific Ocean. Strain DY48A3-103T showed oxidase-positive and catalase-positive activities. Growth was observed at 10-37 °C (optimum 30 °C), at pH 6.5-9.5 (optimum 8.0) and in 1-11% NaCl (optimum 3%, w/v). 16S rRNA gene sequence analysis exhibited 96.3%, 96.1%, 96.0%, and 94.9% sequence similarity to the type strains Rhodophyticola porphyridii MA-7-27T, Nioella sediminis JS7-11T, N. nitratireducens SSW136T, and Jannaschia helgolandensis DSM 14858T, respectively. Strain DY48A3-103T and the type strains of phylogenetically related species have 61.7-75.4% AAI values, which fell into to the genus boundary range (60-80% AAI). Phylogenetic trees based on the 16S rRNA gene sequences and the genome sequences of strain DY48A3-103T revealed that it was affiliated to the members of the family Rhodobacteraceae. The G+C content was 65.4%. The sole isoprenoid quinone was Q-10. The predominant polar lipids were phosphatidylcholine and phosphatidylglycerol. Major fatty acids were summed feature 8 (comprising C18:1ω7c and/or C18:1ω6c), C19:0 cyclo ω8c, and C16:0. On the basis of the phenotypic, chemotaxonomic, and genomic properties, strain DY48A3-103t is proposed to represent a novel genus and a novel species, Alterinioella nitratireducens gen. nov., sp. nov., in the family Rhodobacteraceae. The type strain is DY48A3-103T (= KCTC 72738T = MCCC 1K04322T).