Anaerobic methane oxidation coupled to nitrite reduction can be a potential methane sink in coastal environments

作者：Shen, Li-dong; Hu, Bao-lan^*; Liu, Shuai; Chai, Xiao-ping; He, Zhan-fei; Ren, Hong-xing; Liu, Yan; Geng, Sha; Wang, Wei; Tang, Jing-liang; Wang, Yi-ming; Lou, Li-ping; Xu, Xiang-yang; Zheng, Ping

来源：Applied Microbiology and Biotechnology, 2016, 100(16): 7171-7180.

DOI：10.1007/s00253-016-7627-0

• N-DAMO
• Potential methane sink
• Hangzhou Bay
• Anthropogenic nitrogen pollution
• Coastal environments

In the current study, we investigated nitrite-dependent anaerobic methane oxidation (N-DAMO) as a potential methane sink in the Hangzhou Bay and the adjacent Zhoushan sea area. The potential activity of the N-DAMO process was primarily observed in Hangzhou Bay by means of C-13-labeling experiments, whereas very low or no potential N-DAMO activity could be detected in the Zhoushan sea area. The measured potential N-DAMO rates ranged from 0.2 to 1.3 nmol (CO2)-C-13 g(-1) (dry sediment) day(-1), and the N-DAMO potentially contributed 2.0-9.4 % to the total microbial methane oxidation in the examined sediments. This indicated that the N-DAMO process may be an alternative pathway in the coastal methane cycle. Phylogenetic analyses confirmed the presence of Candidatus Methylomirabilis oxyfera-like bacteria in all the examined sediments, while the group A members (the dominant bacteria responsible for N-DAMO) were found mainly in Hangzhou Bay. Quantitative PCR showed that the 16S rRNA gene abundance of Candidatus M. oxyfera-like bacteria varied from 5.4 x 10(6) to 5.0 x 10(7) copies g(-1) (dry sediment), with a higher abundance observed in Hangzhou Bay. In addition, the overlying water NO3 (-) concentration and salinity were identified as the most important factors influencing the abundance and potential activity of Candidatus M. oxyfera-like bacteria in the examined sediments. This study showed the evidence of N-DAMO in coastal environments and indicated the importance of N-DAMO as a potential methane sink in coastal environments.

• 出版日期2016-8
• 单位浙江大学