title: Molecular Analysis of Methanogen Richness in Landfill and Marshland Targeting 16S rDNA Sequences.
abstract: Methanogens, a key contributor in global carbon cycling, methane emission, and alternative energy production, generate methane gas via anaerobic digestion of organic matter. The methane emission potential depends upon methanogenic diversity and activity. Since they are anaerobes and difficult to isolate and culture, their diversity present in the landfill sites of Delhi and marshlands of Southern Assam, India, was analyzed using molecular techniques like 16S rDNA sequencing, DGGE, and qPCR. The sequencing results indicated the presence of methanogens belonging to the seventh order and also the order Methanomicrobiales in the Ghazipur and Bhalsawa landfill sites of Delhi. Sequences, related to the phyla Crenarchaeota (thermophilic) and Thaumarchaeota (mesophilic), were detected from marshland sites of Southern Assam, India. Jaccard analysis of DGGE gel using Gel2K showed three main clusters depending on the number and similarity of band patterns. The copy number analysis of hydrogenotrophic methanogens using qPCR indicates higher abundance in landfill sites of Delhi as compared to the marshlands of Southern Assam. The knowledge about "methanogenic archaea composition" and "abundance" in the contrasting ecosystems like "landfill" and "marshland" may reorient our understanding of the Archaea inhabitants. This study could shed light on the relationship between methane-dynamics and the global warming process.
authors.affiliation: Department of Biotechnology, Assam University, Silchar, Assam 788011, India.
authors.forename: Shailendra
authors.initials: S
authors.lastname: Yadav
authors.affiliation: Department of Biotechnology, Assam University, Silchar, Assam 788011, India.
authors.forename: Sharbadeb
authors.initials: S
authors.lastname: Kundu
authors.affiliation: Department of Biotechnology, Assam University, Silchar, Assam 788011, India.
authors.forename: Sankar K
authors.initials: SK
authors.lastname: Ghosh
authors.affiliation: School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India.
authors.forename: S S
authors.initials: SS
authors.lastname: Maitra
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D044822:Biodiversity; D016000:Cluster Analysis; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D007194:India; D008697:Methane / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D064091:Waste Disposal Facilities; D053833:Wetlands
chemical_list: D019641:DNA, Archaeal; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D008697:Methane