Strain GY_HT was isolated from an artificial wetland in Okcheon, Chungcheongbuk-do Province, Republic of Korea. Strain GY_HT was closely related to Pseudolabrys taiwanensis CC-BB4T based on 16S rRNA gene sequences (94.7 % similarity) and clustered within the family Nitrobacteraceae. Cells of the isolate were Gram-stain-negative, catalase-negative and oxidase-positive, and colonies were white or pale transparent. A flagellum was observed, and the isolate could respire both aerobically and anaerobically. Growth of GY_ HT was observed in the following conditions: 10-45 °C, pH 5-11 and 0-4 % NaCl. The optimal conditions for growth were 25 °C, pH 6.5-7.5 and 0.5-1.5 % NaCl. The major fatty acids were C19 : 0 cyclo ω8c (35.8 %) and summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c; 27.4 %). The major quinone was found to be ubiquinone-10. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine were the major polar lipids. The G+C content of the genome of GY_HT was 63.3 mol%. Based on its phylogenomic, physiological and biochemical attributes, strain GY_HT represents a novel species of a novel genus of the family Nitrobacteraceae. We propose the name as Undibacter mobilis gen. nov., sp. nov. The type strain is GY_HT (=KCTC 62792T=JCM 32856T).
Keywords: Pseudolabrys; Undibacter; aromatic hydrocarbon; novel bacteria; wetland.