Alsobacter soli sp. nov., a novel bacterium isolated from paddy soil, emended description of the genus Alsobacter and description of the family Alsobacteraceae fam. nov.

Strain SH9T, an aerobic bacterium isolated from a paddy soil sample collected in Shanghai, China, was characterized using a polyphasic approach. It grew optimally at pH 7.0, temperatures of 30–35 °C and in the presence of 1 % (w/v) NaCl. Comparative analysis of 16S rRNA gene sequences showed that strain SH9T fell within the genus Alsobacter , forming a clear cluster with the type strain of Alsobacter metallidurans , with which it exhibited a 16S rRNA gene sequence similarity value of 98.5 %. Cells of strain SH9T were Gram-stain-negative, motile, non-spore-forming, rod-shaped, positive for catalase and oxidase activity, and negative for atmospheric nitrogen fixation and nitrate reduction. The strain was a chemo-organotrophic bacterium, incapable of growth on C1 substrates. The chemotaxonomic properties of strain SH9T were consistent with those of the genus Alsobacter: the predominant ubiquinone was Q-10, and the major fatty acid was summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and phosphatidylmonomethylethanolamine. The DNA G+C content was 68.5 mol%. Strain SH9T exhibited a DNA–DNA relatedness level of 20±2 % with A. metallidurans NBRC 107718T. Based on the data obtained, strain SH9T represents a novel species of the genus Alsobacter , for which the name Alsobacter soli sp. nov. is proposed. The type strain is SH9T (=JCM 32501T=CCTCC AB 2017284T). A new family, Alsobacteraceae fam. nov., is also proposed encompassing strain SH9T and Alsobacter metallidurans NBRC 107718T.