Rhizobium desertarenae sp. nov., isolated from the Saline Desert Soil from the Rann of Kachchh, India

A novel bacterial strain designated ADMK78^T was isolated from the saline desert soil. The cells were rod-shaped, Gram-negative, and non-motile. The strain ADMK78^T grows best at 28°C and pH 7.0 and can tolerate up to 2% (w/v) NaCl. Based on 16S rRNA gene phylogeny, the strain ADMK78^T belongs to the genus Rhizobium, with the highest similarity to Rhizobium wuzhouense W44^T (98.7%) and Rhizobium ipomoeae shin9-1^T (97.9%). Core-genes based phylogenetic analysis revealed that the strain ADMK78^T forms a distinct branch in between Rhizobium ipomoeae shin9-1^T and Rhizobium selenitireducens BAA-1503^T.

The average nucleotide identity of ADMK78^T was less than 82%, to members of the family Rhizobiaceae. The genomic DNA G+C content of strain ADMK78^T is 58.6 mol%. The major fatty acids of strain ADMK78^T were C_18:0 and C_{18:1 ω7c}. The strain ADMK78^T showed differences in physiological, phenotypic, and protein profiles estimated by MALDI-TOF MS to its closest relatives. Based on the phenotypic, chemotaxonomic properties, and phylogenetic analyses, the strain ADMK78^T could be distinguished from the recognized species of the genus Rhizobium.

It is suggested to represent a novel species of this genus, for which the name Rhizobium desertarenae sp. nov. is proposed. The type strain is ADMK78^T (=MCC 3400^T; KACC 21383^T; JCM 33657^T).