Xu Wei, Li Meng, Ding Jie-Fei, Gu Ji-Dong, Luo Zhu-Hua
Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, 178 Daxue Road, Xiamen, 361005, People's Republic of China.
Appl Microbiol Biotechnol. 2014 Sep;98(18):7993-8004. doi: 10.1007/s00253-014-5833-1. Epub 2014 Jun 4.
Ammonia oxidation is the first and rate-limiting step of nitrification, which is carried out by two groups of microorganisms: ammonia-oxidizing bacteria (AOB) and the recently discovered ammonia-oxidizing archaea (AOA). In this study, diversity and abundance of AOB and AOA were investigated in five rock samples from a deep-sea hydrothermal vent site at the Mid-Atlantic Ridge (MAR) of the South Atlantic Ocean. Both bacterial and archaeal ammonia monooxygenase subunit A (amoA) gene sequences obtained in this study were closely related to the sequences retrieved from deep-sea environments, indicating that AOB and AOA in this hydrothermal vent site showed typical deep ocean features. AOA were more diverse but less abundant than AOB. The ratios of AOA/AOB amoA gene abundance ranged from 1/3893 to 1/242 in all investigate samples, indicating that bacteria may be the major members responding to the aerobic ammonia oxidation in this hydrothermal vent site. Furthermore, diversity and abundance of AOA and AOB were significantly correlated with the contents of total nitrogen and total sulfur in investigated samples, suggesting that these two environmental factors exert strong influences on distribution of ammonia oxidizers in deep-sea hydrothermal vent environment.
氨氧化是硝化作用的第一步也是限速步骤，这一过程由两类微生物完成：氨氧化细菌（AOB）和最近发现的氨氧化古菌（AOA）。在本研究中，对来自南大西洋中大西洋海岭（MAR）一处深海热液喷口的五个岩石样本中的AOB和AOA的多样性和丰度进行了调查。本研究中获得的细菌和古菌氨单加氧酶亚基A（amoA）基因序列均与从深海环境中检索到的序列密切相关，这表明该热液喷口处的AOB和AOA呈现出典型的深海特征。AOA比AOB更为多样，但丰度较低。在所有调查样本中，AOA/AOB amoA基因丰度之比在1/3893至1/242之间，这表明细菌可能是该热液喷口处好氧氨氧化的主要成员。此外，AOA和AOB的多样性和丰度与调查样本中的总氮和总硫含量显著相关，这表明这两个环境因素对深海热液喷口环境中氨氧化菌的分布有强烈影响。
