PLoS ONE (Jan 2012)

Comparative metagenomic analysis of soil microbial communities across three hexachlorocyclohexane contamination levels.

  • Naseer Sangwan,
  • Pushp Lata,
  • Vatsala Dwivedi,
  • Amit Singh,
  • Neha Niharika,
  • Jasvinder Kaur,
  • Shailly Anand,
  • Jaya Malhotra,
  • Swati Jindal,
  • Aeshna Nigam,
  • Devi Lal,
  • Ankita Dua,
  • Anjali Saxena,
  • Nidhi Garg,
  • Mansi Verma,
  • Jaspreet Kaur,
  • Udita Mukherjee,
  • Jack A Gilbert,
  • Scot E Dowd,
  • Rajagopal Raman,
  • Paramjit Khurana,
  • Jitendra P Khurana,
  • Rup Lal

DOI
https://doi.org/10.1371/journal.pone.0046219
Journal volume & issue
Vol. 7, no. 9
p. e46219

Abstract

Read online

This paper presents the characterization of the microbial community responsible for the in-situ bioremediation of hexachlorocyclohexane (HCH). Microbial community structure and function was analyzed using 16S rRNA amplicon and shotgun metagenomic sequencing methods for three sets of soil samples. The three samples were collected from a HCH-dumpsite (450 mg HCH/g soil) and comprised of a HCH/soil ratio of 0.45, 0.0007, and 0.00003, respectively. Certain bacterial; (Chromohalobacter, Marinimicrobium, Idiomarina, Salinosphaera, Halomonas, Sphingopyxis, Novosphingobium, Sphingomonas and Pseudomonas), archaeal; (Halobacterium, Haloarcula and Halorhabdus) and fungal (Fusarium) genera were found to be more abundant in the soil sample from the HCH-dumpsite. Consistent with the phylogenetic shift, the dumpsite also exhibited a relatively higher abundance of genes coding for chemotaxis/motility, chloroaromatic and HCH degradation (lin genes). Reassembly of a draft pangenome of Chromohalobacter salaxigenes sp. (∼8X coverage) and 3 plasmids (pISP3, pISP4 and pLB1; 13X coverage) containing lin genes/clusters also provides an evidence for the horizontal transfer of HCH catabolism genes.