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bioRxiv · 10.1101/2022.03.21.485241

Genome-resolved metagenomics reveals cohesive metabolic dynamics, metal resistance genes (MRGs) and biogeochemical cycling in a hot spring system

Nagar, S.·Bharti, M.·Negi, R. K.
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Abstract

The hot spring microbiome is a complex assemblage of micro- and geochemistry of this spring have been and macro- organisms, however, the understanding and projection of enzymatic repertoire that access earths integral ecosystem processes remains limited. The composite microbial communities drive global carbon, sulfur, oxygen, iron and nitrogen cycles and other metabolic mechanism involved in heavy metal tolerance and degradation. Interestingly, the Khirganga hot spring microbiome displayed an astounding taxonomical diversity revealed by examination of 41 high and medium qualified metagenome-assembled genomes (MAGs) from at least 12 bacterial and 2 archaeal phyla. Over 1749 genes putatively involved in crucial metabolism of elements viz. nitrogen, phosphorous, sulfur and 598 genes encoding enzymes for metals resistance from cadmium, zinc, chromium, arsenic and copper. The MAGs also possess 229 biosynthetic gene clusters dominated by bacteriocins and terpenes could be exploited in medicinal industries. Their metabolic roles found to be altering linkages in biogeochemical cycles and explored a discerned rate of carbon fixation exclusively in archaeal member Methanospirillum hungatei. Higher Pfam entropy scores in Proteobacteria members highlighting their major contribution in sequestration of ammonia, nitrate and sulfate components as electron acceptors. Through these results, we could postulate that few novel organisms within the community can conduct multiple sequential redox conversions and also considered in reducing emergent difficulties of waste water treatment plants and biotechnological applications.

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Nagar, S., Bharti, M., Negi, R. K.. 2022-03-22. Genome-resolved metagenomics reveals cohesive metabolic dynamics, metal resistance genes (MRGs) and biogeochemical cycling in a hot spring system. https://doi.org/10.1101/2022.03.21.485241

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