Taxonomic and Functional Metagenomics Profiling of Tuwa and Unnai Hot Springs Microbial Communities

Hot springs are of great importance due to their unique physicochemical properties. Due to unique selection pressure in this habitat, a diverse microbial community is prevailing and can be analyzed by high throughput sequencing technology. Present study focuses on metagenomic sequencing of two hot springs from Gujarat, India namely Tuwa and Unnai through both, culturable and culture independent approach. Sequence analysis from both the water reservoirs depicted higher species richness and diversity based on various diversity indices. The microbial community structure at both the hot springs was distinct and dependent on physicochemical factors like temperature, pH, mineral content etc. Enrichment by cultivation before metagenome sequencing revealed the abundance of Firmicutes (up to 96%) representing cultivable organisms in hotsprings. The bacterial phyla Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Deinococcus-Thermus, and Chloroflexi dominate the thermoalkaline spring at Unnai and Tuwa in different proportion. Economically important microorganisms belonging to genera Thermus, Brevibacillus, Anoxybacillus, Bacillus, Pseudomonas, and Geobacillus were prevalent in hot springs. The analysis of functional potential by KEGG revealed pathways for metabolism of carbohydrates, amino acids, vitamins, cofactors and xenobiotics. Annotation with Carbohydrate Active EnZymes (CAZy) revealed the presence of four major classes of enzymes: glycosyl transferase, glycoside hydrolase, polysaccharide lyase and carbohydrate-binding modules. The study provides insight into the microbial community structure and their untapped functional potential for various biotechnological and environmental applications.