By- Dr. Amaraja Joshi
Team of Dr. Amaraja Joshi and Dr. Tushar Lodha at NCMR-NCCS, Pune has recently reclassified Genus Alkalihalobacillus into seven new genera for which the names Alkalihalobacterium gen. nov., Halalkalibacterium gen. nov., Halalkalibacter gen. nov., Shouchella gen. nov., Pseudalkalibacillus gen. nov., Alkalicoccobacillus gen. nov., and Alkalihalophilus gen. nov. are proposed and published validly under ICNP. While exploring the bacterial diversity of alkaline Lonar Lake, an antimicrobial compound producing alkaliphilic, moderately halophilic bacterial strain designated as MEB199T was isolated from the sediment sample. Its taxonomic position was determined by employing a polyphasic taxonomic approach including whole genome-based analysis. During the assessment of the taxonomic status of the strain MEB199T, it was observed that the genome-based phylogenetic analysis and overall genome relatedness index (OGRI) indicated that the genus Alkalihalobacillus is composed of heterogeneous members, and its reclassification is required. The intra-clade average amino acid identity (AAI) and percentage of conserved proteins (POCP) range from 52 to 68% and 37 to 59%, respectively, which are interspersed on the intra-genera cutoff values; therefore taxonomy of genus Alkalihalobacillus was reassessed. Apart from having phylogenetic differences, members of the genus Alkalihalobacillus also differ in phenotypic characters such as morphology, growth requirement, polar lipids, and fatty acid composition. Based on phenotypic characteristics, phylogenetic analysis, and OGRI, the reclassification of genus Alkalihalobacillus into seven new genera was proposed. Based on digital DNA–DNA hybridization (dDDH) and ANI value, it was noticed that Alkalihalobacillus halodurans DSM 497T and Alkalihalobacillus okuhidensis DSM 13666T belong to the same species. Therefore, our team propose Alkalihalobacillus okuhidensis as a heterotypic synonym of Alkalihalobacillus halodurans.
Microbe World 