Pacificispira spongiicola gen. nov., sp. nov., a nitrate-reducing bacterium isolated from tropical western Pacific

The Gram-stain-negative, strictly aerobic, curved-to-spiral rod-shaped bacterial strain, designated KN72T, was isolated from the Caroline Seamounts in the Pacific Ocean. Phylogenetic analysis of 16S rRNA gene sequences revealed that strain KN72T was a member of the family Rhodospirillaceae and formed a distinct lineage. Strain KN72T contained ubiquinone-10 as the major respiratory quinone. The polar lipid profiles contained phosphatidylethanolamine, phosphatidylglycerol, one aminolipid and three phospholipids. The predominant cellular fatty acids were C16:0 and summed feature 8 (comprising C18:1ω7c/C18:1ω6c). The strain KN72T displayed highest 16S rRNA gene sequence similarities with Hwanghaeella grinnelliae Gri0909T (92.3%), Marivibrio halodurans ZB80T (91.0%) and Aestuariispira insulae AH-MY2T (90.1%). The DNA G+C content of strain KN72T was 61.1%. Collectively, based on phenotypic, chemotaxonomic, phylogenetic and genomic evidence presented, strain KN72T represents a novel species of a novel genus of the family Rhodospirillaceae, for which the name Pacificispira spongiicola gen. nov., sp. nov. is proposed. The type strain is KN72T (= CGMCC 1.17142T = KCTC 72429T).