Urechidicola croceus gen. nov., sp. nov., a member of the family Flavobacteriaceae

Abstract

A Gram-stain-negative, rod-shaped, non-flagellated, non-gliding, aerobic bacterial strain, designated LPB0138(T), was isolated from a marine spoon worm (Urechis unicinctus). The strain LPB0138(T) contains a circular chromosome of 3.43 Mb with a DNA G+C content of 30.4 mol%. The genome includes 2987 protein-coding genes and two copies of rRNA operons. The 165 rRNA gene sequence analysis showed that the isolate occurred within a Glade containing only members of the family Flavobacteriaceae. The highest sequence similarity was observed with the genus Lutibacter (93.0-94.3%), but the phylogenetic leaf of the new isolate did not belong to any of the genera known in the family Flavobacteriaceae. The low sequence similarity and the phylogenetic tree topology implied the novel generic status of the new isolate. The phenotypic properties of the strain LPB0138(T) also differentiated this isolate from its neighbour genera by showing a distinctive fatty acid composition, unique polar lipids profile, and low DNA G+C content. The LPB0138T strain contained menaquinone 6 as the isoprenoid quinone; iso-C-15:1, G iso-C-15:0, iso-C-15:0 3-OH, and iso-C-17:0 3-OH as the major fatty acids; and phosphatidylethanolamine, unidentified aminophospholipids. unidentified aminolipids, and unidentified lipids as the major polar lipids. Based on the polyphasic taxonomic data obtained, the LPB0138(T) strain is considered to represent a novel species in a novel genus of the family Flavobacteriaceae, for which the name Urechidicola croceus gen. nov., sp. nov. was proposed. The type strain is LPB0138(T) (=KACC 18889(T):=JCM 31563(T)).