Metagenomic landscape of sediments of river Ganga reveals microbial diversity, potential plastic and xenobiotic degradation enzymes

Ajaya Kumar Rout; Sangita Dixit; Partha Sarathi Tripathy; Sushree Swati Rout; Satya Narayan Parida; Pranaya Kumar Parida; Dhruba Jyoti Sarkar; Basanta Kumar Das; Ashok Kumar Singh; Bijay Kumar Behera

doi:10.1016/j.jhazmat.2024.134377

Metagenomic landscape of sediments of river Ganga reveals microbial diversity, potential plastic and xenobiotic degradation enzymes

J Hazard Mater. 2024 Apr 21:471:134377. doi: 10.1016/j.jhazmat.2024.134377. Online ahead of print.

Affiliations

¹ Aquatic Environmental Biotechnology and Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute, Barrackpore, 700120 Kolkata, West Bengal, India; Department of Biosciences and Biotechnology, Fakir Mohan University, Balasore 756089, Odisha, India.
² Center for Biotechnology, School of Pharmaceutical Sciences, Siksha 'O' Anusandhan (Deemed to Be University), Bhubaneswar 751003, India.
³ Faculty of Biosciences and Aquaculture, Nord University, Universitetsalléen 11, 8026 Bodø, Norway; Rani Lakshmi Bai Central Agricultural University, Jhansi 284003, Uttar Pradesh, India.
⁴ Department of Biosciences and Biotechnology, Fakir Mohan University, Balasore 756089, Odisha, India.
⁵ Rani Lakshmi Bai Central Agricultural University, Jhansi 284003, Uttar Pradesh, India.
⁶ Aquatic Environmental Biotechnology and Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute, Barrackpore, 700120 Kolkata, West Bengal, India.
⁷ Aquatic Environmental Biotechnology and Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute, Barrackpore, 700120 Kolkata, West Bengal, India; Rani Lakshmi Bai Central Agricultural University, Jhansi 284003, Uttar Pradesh, India. Electronic address: beherabk18@yahoo.co.in.

PMID: 38663298
DOI: 10.1016/j.jhazmat.2024.134377

Abstract

The Ganga is the largest river in India, serves as a lifeline for agriculture, drinking water, and religious rites. However, it became highly polluted due to the influx of industrial wastes and untreated sewages, leading to the decline of aquatic biodiversity. This study investigated the microbial diversity and plastic-xenobiotic degrading enzymes of six sediment metagenomes of river Ganga at Prayagraj (RDG, TSG, SDG) and Devprayag (KRG, BNG, BRG). The water quality parameters, higher values of BOD (1.8-3.7 ppm), COD (23-29.2 ppm) and organic carbon (0.18-0.51%) were recorded at Prayagraj. Comparative analysis of microbial community structure between Prayagraj and Devprayag revealed significant differences between Bacteroidetes and Firmicutes, which emerging as the predominant bacterial phyla across six sediment samples. Notably, their prevalence was highest in the BRG samples. Furthermore, 25 OTUs at genus level were consistent across all six samples. Alpha diversity exhibited minimal variation among samples, while beta diversity indicated an inverse relationship between species richness and diversity. Co-occurrence network analysis established that genera from the same and different groups of phyla show positive co-relations with each other. Thirteen plastic degrading enzymes, including Laccase, Alkane-1 monooxygenase and Alkane monooxygenase, were identified from six sediment metagenomes of river Ganga, which can degrade non-biodegradable plastic viz. Polyethylene, Polystyrene and Low-density Polyethelene. Further, 18 xenobiotic degradation enzymes were identified for the degradation of Bisphenol, Xylene, Toluene, Polycyclic aromatic hydrocarbon, Styrene, Atrazene and Dioxin etc. This is the first report on the identification of non-biodegradable plastic degrading enzymes from sediment metagenomes of river Ganga, India. The findings of this study would help in pollution abatement and sustainable management of riverine ecosystem.

Keywords: Metagenomics; Microbial diversity; Plastic degrading enzyme; River Ganga; Sediment; Xenobiotic degradation.