Craterilacuibacter sinensis gen. nov. sp. nov., isolated from a crater lake in China

Two bacterial strains, designated B2N2-7(T) and B2N2-12, were isolated from Buteha crater lake in the Greater Khingan Mountain of China. The two strains were Gram-stain-negative, non-spore-forming, motile with a single polar flagellum, short rod-shaped bacteria. They were catalase- and oxidase-positive. Optimal growth occurred at 20-25 degrees C. at pH 7.5-8.0 and with 0-1.0% (w/v) NaCl. Based on phylogenomic analysis, strains B2N2-7(T) and B2N2-12 were assigned to the family Neisseriaceae, and their 16S rRNA gene sequences showed the highest similarities to that of Aquitalea denitrificans 5YN1-3(T) (<94.2 %). The predominant cellular fatty acids were C-16:0 and summed feature 3 (comprising C-16:1 omega 7c/C-16:1 omega 6c). The major respiratory quinone was ubiquinone 8 (Q-8). The polar lipids were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), two unidentified aminophospholipids (APL) and some unidentified lipids (L). The genomic DNA G+C content of strain B2N2-7(T) was 59.4mol% according to the genomic sequencing result. Based on the phylogenetic, genotypic and chemotaxonomic analyses, the two strains are proposed to represent a novel species of a new genus in the family Neisseriaceae, named Craterilacuibacter sinensis gen. nov., sp. nov. The type strain of Craterilacuibacter sinensis is B2N2-7(T) (=CGMCC 1.17189(T) =KCTC 73735(T)): B2N2-12 (=CGMCC 1.17190=KCTC 72734) is a second strain of the species.