De novo genome assembly and comparative annotation reveals metabolic versatility in cellulolytic bacteria from...

Cellulose, the most abundant polysaccharide in nature, is a rich source of renewable energy and sustains soil nutrients. Among the microorganisms known to degrade cellulose, bacteria are less studied compared to fungi. In the present work, we have investigated the culturable bacteria actively involved in cellulose degradation in forest and crop field soils. Based on clear zone formation and enzyme activity assay, we identified 7 bacterial strains positive for cellulose degradation. Of these, two most efficient strains (Bacillus cereus strains BHU1 and BHU2) were selected for whole genome sequencing, annotation, and information regarding GC content, number of genes, total subsystems, starch, and cellulose degradation pathways. Average nucleotide identity (ANI) showed more than 90% similarity between both the strains (BHU1 and BHU2) and with B. cereus ATCC 14579. Both the strains have genes and enzyme families like endoglucanase and β-glucosidase as evident from whole genome sequence. Cellulase containing gene families (GH5, GH8, GH1), and many other carbohydrate-degrading enzymes, were present in both the bacterial strains. Taken together, the results suggest that the strains were efficient in cellulose degradation, and can be used for energy generation and production of value-added product.