A novel facultatively anaerobic bacterium, designated strain LAM-WHM-D11T, was isolated from a frozen soil sample of China. Cells of strain LAM-WHM-D11T were observed to be Gram-stain negative, non-motile and rod-shaped. Colonies were yellowish, and circular with convex shape. Strain LAM-WHM-D11T was found to be able to grow at 4-40 °C (optimum 15 °C), pH 7.5-2.0 (optimum 9.5) and 0-2.5% NaCl (w/v) (optimum 1.5%). The 16S rRNA gene sequence similarity analysis showed that strain LAM-WHM-D11T is closely related to Arenimonas metalli CF5-1T (98.0%), Arenimonas aquaticum NA-09T (97.9%), Arenimonas donghaensis HO3-R19T (95.6%) and Arenimonas aestuarii S2-21T (95.3%). The DNA-DNA hybridization values between the isolate and A. metalli CGMCC 1.10787T, A. aquaticum KACC 14663T, A. donghaensis KACC 11381T were 41.0 ± 1.7, 44.7 ± 1.4 and 42.8 ± 1.2%, respectively. The genomic DNA G+C content was found to be 66.5 mol% as determined by the T m method. The major cellular fatty acids were identified as iso-C15:0 and iso-C16:0. The major isoprenoid quinone was identified as ubiquinone 8 (Q-8). The major polar lipids were found to be diphosphatidyglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmonomethylethanolamine, two phospholipids and five unidentified lipids. Based on the phylogenetic, phenotypic and chemotaxonomic characteristics, strain LAM-WHM-D11T is concluded to represent a novel species within the genus Arenimonas, for which the name Arenimonas alkanexedens sp. nov. is proposed. The type strain is LAM-WHM-D11T (ACCC 19750T = JCM 30464T).
Keywords: 16S rRNA gene; Arenimonas alkanexedens sp. nov.; Frozen soil sample; Polyphasic taxonomy.