Mesorhizobium ephedrae sp. nov. isolated from the roots of Ephedra przewalskii in Kumtag desert.

Abstract

Strain 6GN-30T, a Gram-stain-negative, aerobic, non-spore-forming, rod-shaped, motile bacterium was isolated from Ephedra sinica roots in the Kumtag Desert. On the basis of the 16S rRNA gene sequence, the isolate represented a member of the genus Mesorhizobium of the family Phyllobacteriaceae. The results of a phylogenetic analysis indicated that 6GN-30T was phylogenetically related to Mesorhizobium soliNHI-8T. Strain 6GN-30T grew at a salinity of 0-1.0 % (w/v) NaCl (with optimum growth in the absence of NaCl), pH 6.0-9.0 (optimum 7.0-8.0) and 15-45 °C. The major cellular fatty acids were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c), C19 : 0cyclo ω8c, iso-C17 : 0, C18 : 0, and C16 : 0. The draft genome of 6GN-30T was 6.11 Mb long, with a DNA G+C content of 66.4 mol%. The average nucleotide identity to M. soliNHI-8T was 84.32 %. The strain contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine,aminophospholipids and phospholipids. The chemotaxonomic, phylogenetic and phenotypic data indicate that 6GN-30T represents a novel species of the genus Mesorhizobiumfor which the name Mesorhizobiumephedrae sp. nov. is proposed. The type strain is 6GN-30T (=ACCC 60073T=KCTC 62410T).