Unveiling the Biodiversity of Hyperthermophilic Archaea in Jharia Coal Mines: Potential Threat to Methanogenesis?

Priyanka Jha; Joginder Singh; Ambarish S Vidyarthi; Ram Prasad

doi:10.2174/1389202921999200605151722

Unveiling the Biodiversity of Hyperthermophilic Archaea in Jharia Coal Mines: Potential Threat to Methanogenesis?

Curr Genomics. 2020 Aug;21(5):363-371. doi: 10.2174/1389202921999200605151722.

Authors

Priyanka Jha¹, Joginder Singh¹, Ambarish S Vidyarthi¹, Ram Prasad¹

Affiliation

¹ 1Amity Institute of Biotechnology, Amity University, Kolkata, West Bengal700156, India; 2Department of Microbiology, School of Bioengineering and Biosciences, Lovely Professional University, Punjab, India; 3N.P.S Institute of Technology, GIC Campus, Pithoragarh, Uttarakhand, India; 4Department of Botany, Mahatma Gandhi Central University, Motihari-845401, Bihar, India.

Abstract

Aim: To examine the biodiversity of archaeal sulfate reducers and methanogens present in the underground coal mines of Jharia using metagenomics and pyrosequencing.

Objectives: 1) Bioinformatical analysis of the metagenomic data related to a taxonomic analysis obtained from the coal to investigate complete archaeal taxonomic features of the coal bed methane (CBM) microbiome. 2) Bioinformatical analysis of the metagenomic data related to a functional analysis obtained from the coal to investigate functional features relating to taxonomic diversity of the CBM microbiome. 3) The functional attributes have been examined specifically for ORFs related to sulfite reduction and methanogenesis.The taxonomic and functional biodiversity related to euryarchaeota will help in a better understanding of the obstacles associated with methane production imposed by the sulfate reducers.

Background: The microbial methanogenesis in the coal microbiome is a resultant of substrate utilization by primarily fermentative bacteria and methanogens. The present work reveals the biodiversity of archaeal sulfate reducers and methanogens present in the underground coal mines of Jharia using metagenomics and pyrosequencing.

Methodology: Bioinformatical analysis for structural and functional attributes was accomplished using MG-RAST. The structural analysis was accomplished using RefSeq database, whereas the functional analysis was done via CoG database with a cut off value, a sequence percent identity, and sequence alignment length cut off of 1e^-5, 60% and 45, respectively.

Results: Attained communities revealed the dominance of hyperthermophilic archaea Pyrococcus furiosus along with Thermococcus kodakarensis in the coal metagenome.The obtained results also suggest the presence of dissimilatory sulfite reductase and formylmethanofuran dehydrogenase, formylmethanofuran: tetrahydromethanopterin formyltransferase involved in sulfite reduction and methanogenesis, respectively, in the microbiome.

Conclusion: This report is the first attempt to showcase the existence of specific euryarchaeal diversity and their related functional attributes from Jharia coal mines through high throughput sequencing. The study helps in developing a better understanding of the presence of indigenous microbes (archaea) and their functions in the coal microbiome, which can be utilized further to resolve the energy crisis.

Keywords: Euryarchaeota; SRBs; metagenomics; pyrosequencing; sulfite reductase; thermococcales.