Alsobacter metallidurans gen. nov., sp nov., a thallium-tolerant soil bacterium in the order Rhizobiales

A thallium-tolerant, aerobic bacterium, designated strain SK200a-9(T), isolated from a garden soil sample was characterized using a polyphasic approach. Comparative analysis of 16S rRNA gene sequences revealed that strain SK200a-9(T) was affiliated with an uncultivated lineage within the Alphaproteobacteria and the nearest cultivated neighbours were bacteria in genera in the family Methylocystaceae (93.3-94.40/o 16S rRNA gene sequence similarity) and the family Beijerinckiaceae (92.3-93.1 %) in the order Rhizobiales. Cells of strain SK200a-9(T) were Gram-stain-negative, non-motile, non-spore-forming, poly-beta-hydrovbutyrate-accumulating rods. The strain was a chemo-organotrophic bacterium, which was incapable of growth on Cl substrates. Catalase and oxidase were positive. Atmospheric nitrogen fixation and nitrate reduction were negative. The strain contained ubiquinone Q-10 and cellular fatty acids C-18:1 omega 7c, C-18:0, C-16:1 omega 7c and C-16:0 as predominant components. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and phosphatidylglycerol. The DNA G+C content was 64.8 mol%. On the basis of the information described above, strain SK200a-9(T) is considered to represent a novel species of a new genus in the order Rhizobiales, for which the name Alsobacter metallidurans gen. nov., sp. nov. is proposed. The type strain of Alsobacter metallidurans is SK200a-9(T) (=NBRC 107718(T)=CGMCC 1.12214(T)).