Yadav Shailendra, Kundu Sharbadeb, Ghosh Sankar K, Maitra S S
Department of Biotechnology, Assam University, Silchar, Assam 788011, India.
School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India.
Archaea. 2015 Oct 13;2015:563414. doi: 10.1155/2015/563414. eCollection 2015.
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.
产甲烷菌是全球碳循环、甲烷排放和替代能源生产的关键贡献者，通过对有机物进行厌氧消化来产生甲烷气体。甲烷排放潜力取决于产甲烷菌的多样性和活性。由于它们是厌氧菌，难以分离和培养，因此利用16S rDNA测序、变性梯度凝胶电泳（DGGE）和定量聚合酶链反应（qPCR）等分子技术，对印度德里垃圾填埋场和阿萨姆邦南部沼泽地中的产甲烷菌多样性进行了分析。测序结果表明，在德里的加济布尔和巴尔萨瓦垃圾填埋场中存在属于第七目以及甲烷微菌目的产甲烷菌。在印度阿萨姆邦南部的沼泽地中检测到了与泉古菌门（嗜热菌）和奇古菌门（嗜中温菌）相关的序列。使用Gel2K对DGGE凝胶进行的杰卡德分析显示，根据条带模式的数量和相似性可分为三个主要聚类。利用qPCR对氢营养型产甲烷菌的拷贝数分析表明，与阿萨姆邦南部的沼泽地相比，德里垃圾填埋场中的氢营养型产甲烷菌丰度更高。关于“产甲烷古菌组成”和“丰度”在“垃圾填埋场”和“沼泽地”等不同生态系统中的知识，可能会重新调整我们对古菌群落的理解。这项研究有助于揭示甲烷动态与全球变暖过程之间的关系。
