Genomic insights of an alkaliphilic bacterium Halalkalibacter alkaliphilus sp. nov. isolated from an Indian Soda Lake.

Abstract

An alkaliphilic, Gram-stain-positive, non-motile, rod-shaped, and spore forming bacterial strain (MEB205T) was isolated from sediment sample collected from Lonar lake, India. The strain grew optimally at pH 10, NaCl concentration of 3.0% at 37°C. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain MEB205T belonged to the genus Halalkalibacter in the family Bacillaceae and shared the highest sequence similarity with H. okhensis Kh10-101T (98.9%) followed by H. wakoensis N-1T (98.7%). The assembled genome of strain MEB205T has a total length of 4.8Mb with a G + C content of 37.8%. The dDDH and OrthoANI values between strain MEB205T and H. okhensis Kh10-101T were 29.1% and 84.3%, respectively. Furthermore, the genome analysis revealed the presence of antiporter genes (nhaA and nhaD) and L-ectoine biosynthesis gene required for survival of the strain MEB205T in alkaline-saline habitat. The major fatty acid was C15:0 anteiso, C16:0 and C15:0 iso (> 10.0%). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were the major polar lipids. meso-diaminopimelic acid was diagnostic diamino acid for cell wall peptidoglycan. Based on the polyphasic taxonomic studies, strain MEB205T represent a novel species of the genus Halalkalibacter for which the name Halalkalibacter alkaliphilus sp. nov. (Type strain MEB205T = MCC 3863T = JCM 34004T = NCIMB 15406T) is proposed.