Draft genome and description of Consotaella salsifontis gen. nov. sp. nov., a halophilic, free-living, nitrogen-fixing alphaproteobacterium isolated from an ancient terrestrial saline spring.

A free-living, nitrogen-fixing, mesophilic and facultative aerobe, designated strain USBA 369(T), was isolated from a terrestrial saline spring of the Colombian Andes. The non-sporulating rods (1.5×0.8 µm) with rounded ends stained Gram-negative and were motile by means of lophotrichous flagella. The strain grew optimally at 30 °C, at pH 6.9-7.5 and with 1.5 % (w/v) NaCl. The major fatty acids detected were C18 : 1ω7c and C19 : 0 cyclo ω8c, and the respiratory lipoquinone ubiquinone 10 (Q-10) was present. The genome consisted of 4.65 Mb with a DNA G+C content of 64.3 mol%. A total of 4371 genes were predicted and, of those, 4300 were protein coding genes and 71 were RNA genes. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain USBA 369(T) formed a different lineage within the class Alphaproteobacteria, order Rhizobiales, and DNA homology studies with the most closely related genera, Aurantimonas, Aureimonas and Rhizobium (95 % 16S rRNA gene sequence similarity), showed values of <15 %. The phylogenomic analysis provided evidence for clear phylogenetic divergence between strain USBA 369(T) and the closely related genera. On the basis of the phenotypic, chemotaxonomic and phylogenomic evidence, strain USBA 369(T) is considered to represent a novel genus and a novel species for which the name Consotaella salsifontis gen. nov., sp. nov. is proposed. The type strain is USBA 369(T) (=KCTC 22549(T)=CMPUJ U369(T)).