A novel Gram-stain-negative, non-spore-forming, obligate aerobic, motile, rod-shaped, and flagellated bacterium, designated S11R28T, was isolated from the intestinal tract of a Korean shiner, Coreoleuciscus splendidus. Based on 16S rRNA gene sequences, strain S11R28T was identified as member of the genus Undibacterium in class Betaproteobacteria, and was closely related to Undibacterium parvum DSM 23061T (98.49 %). The isolate grew at 4-25 °C, pH 6-9, with 0 % (w/v) NaCl, and grew optimally at 20 °C, pH 8, in the absence of NaCl. The main cellular fatty acids were C16 : 0 and summed features 3 (C16 : 1ω7c and/or C16 : 1ω6c). The strain possessed diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as predominant polar lipids, and ubiquinone Q-8 as a respiratory quinone. The polyamine profile composed of 2-hydroxyputrescine, spermidine, putrescine, and benzoic acid. A genomic DNA G+C content was 51.4 mol%. The average nucleotide identity between strains S11R28T and U. parvum DSM 23061T was 78.66 %. Thus, Undibacterium piscinae can be considered a novel species within the genus Undibacterium with the type strain S11R28T (=KCTC 62668T=JCM 33224T).
Keywords: Korean shiner; Undibacterium; Undibacterium piscinae; gut microbiota.