Bizionia psychrotolerans sp. nov., a psychrophilic bacterium isolated from the intestine of a sea cucumber (Apostichopus japonicus)

A novel Gram-negative, non-flagellated, non-gliding, rod-shaped bacterial strain, designated PB-M7^T, was isolated from the intestine of a sea cucumber collected from Pohang, South Korea. Growth was observed at 4–30 °C (optimum, 25 °C), pH 6.0–9.0 (optimum, pH 7.0–8.0), and with 2.0–6.0 % (w/v) NaCl (optimum, 2.0 %). In a phylogenetic analysis based on 16S rRNA gene sequences, strain PB-M7^T was found to belong to the genus Bizionia and to be most closely related to Bizionia echini KMM 6177^T (99.0 % 16S rRNA gene sequence similarity), Bizionia hallyeonensis T-y7^T (97.9 %), Bizionia algoritergicola APA-1^T (97.5 %), Bizionia argentinensis JUB59^T (97.5 %) and Bizionia myxarmorum ADA-4^T (97.1 %). The predominant fatty acids of strain PB-M7^T were identified as iso-C_15:0 (22.2 %), iso-C_15:1 G (10.8 %), iso-C_17:0 3-OH (16.7 %) and summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c; 11.2 %). The major respiratory quinone was identified as menaquinone-6 (MK-6). The polar lipid profile of strain PB-M7^T was found to contain phosphatidylethanolamine, an unidentified phospholipid, three unidentified aminolipids and three unidentified lipids. The DNA G + C content of strain PB-M7^T was determined to be 33.4 mol% and the mean DNA–DNA relatedness values with the type strains of B. echini, B. hallyeonensis, B. algoritergicola, B. argentinensis, and B. myxarmorum were 52.9, 48.5, 46.5, 37.1 and 26.6 %, respectively. Based on the data presented, strain PB-M7^T represents a novel species of the genus Bizionia, for which the name Bizionia psychrotolerans sp. nov. is proposed. The type strain of B. psychrotolerans is PB-M7^T (= KCCM 43042 ^T = JCM 19924 ^T).