Characterization of Methane Degradation and Methane-Degrading Microbes in Alaska Coastal Water

doi:10.2172/1051498

GSTDTAP > 地球科学

DOI	10.2172/1051498
报告编号	None
来源ID	OSTI ID: 1051498
	Characterization of Methane Degradation and Methane-Degrading Microbes in Alaska Coastal Water
	Kirchman, David L. [Univ. of Delaware, Lewes, DE (United States)]
	2012-03-29
出版年	2012
页数	23
语种	英语
国家	美国
领域	地球科学
英文摘要	The net flux of methane from methane hydrates and other sources to the atmosphere depends on methane degradation as well as methane production and release from geological sources. The goal of this project was to examine methane-degrading archaea and organic carbon oxidizing bacteria in methane-rich and methane-poor sediments of the Beaufort Sea, Alaska. The Beaufort Sea system was sampled as part of a multi-disciplinary expedition (Methane in the Arctic Shelf or MIDAS) in September 2009. Microbial communities were examined by quantitative PCR analyses of 16S rRNA genes and key methane degradation genes (pmoA and mcrA involved in aerobic and anaerobic methane degradation, respectively), tag pyrosequencing of 16S rRNA genes to determine the taxonomic make up of microbes in these sediments, and sequencing of all microbial genes (metagenomes ). The taxonomic and functional make-up of the microbial communities varied with methane concentrations, with some data suggesting higher abundances of potential methane-oxidizing archaea in methane-rich sediments. Sequence analysis of PCR amplicons revealed that most of the mcrA genes were from the ANME-2 group of methane oxidizers. According to metagenomic data, genes involved in methane degradation and other degradation pathways changed with sediment depth along with sulfate and methane concentrations. Most importantly, sulfate reduction genes decreased with depth while the anaerobic methane degradation gene (mcrA) increased along with methane concentrations. The number of potential methane degradation genes (mcrA) was low and inconsistent with other data indicating the large impact of methane on these sediments. The data can be reconciled if a small number of potential methane-oxidizing archaea mediates a large flux of carbon in these sediments. Our study is the first to report metagenomic data from sediments dominated by ANME-2 archaea and is one of the few to examine the entire microbial assemblage potentially involved in anaerobic methane oxidation.
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来源平台	US Department of Energy (DOE)
引用统计
文献类型	科技报告
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/5585
专题	地球科学
推荐引用方式 GB/T 7714	Kirchman, David L. [Univ. of Delaware, Lewes, DE . Characterization of Methane Degradation and Methane-Degrading Microbes in Alaska Coastal Water,2012.