Salinity gradients shape the nitrifier community composition in Nanliu River Estuary sediments and the ecophysiology of comammox Nitrospira inopinata
Salinity gradients shape the nitrifier community composition in Nanliu River Estuary sediments and the ecophysiology of comammox Nitrospira inopinata
复制标题
盐度梯度塑造南流河口沉积物硝化菌群落组成及comammox Nitrospira inopinata的生态生理学
DOI：
10.1016/j.scitotenv.2021.148768
复制
发表时间：
2021
影响因子：
9.8
通讯作者：
Han Ping
中科院分区：
文献类型：
--
作者：
Zhao Mengyue;Tang Xiufeng;Sun Dongyao;Hou Lijun;Liu Min;Zhao Qiang;Klumper Uli;Quan Zhexue;Gu Ji-Dong;Han Ping
The recent discovery of complete ammonia oxidizers (comammox), which convert ammonia to nitrate in a single organism, revolutionized the conventional understanding that two types of nitrifying microorganisms have to be involved in the nitrification process for more than 100 years. However, how different types of nitrifiers in response to salinity change remains largely unclear. This study not only investigated nitrifier community (including ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), comammox and nitrite-oxidizingNitrospira) in the Nanliu estuary to find the ecological relationship between salinity and functional communities and also studied the physiology of a typical comammoxNitrospira inopinatain response to a salinity gradient. Based on sequences retrieved with four sets of functional gene primes, comammoxNitrospirawas in general, mainly composed of clade A, with a clear separation of clade A1 subgroup in all samples and clade A2 subgroup in low salinity ones. As expected, group I.1b and group I.1a AOA dominated the AOA community in low- and high-salinity samples, respectively.Nitrosomonas-AOB were detected in all samples while Nitrosospira-AOB were mainly found in relatively high-salinity samples. Regarding generalNitrospira, lineages II and IV were the major groups in most of the samples, while lineage INitrospirawas only detected in low-salinity samples. Furthermore, the comammox pure culture ofN. inopinatashowed an optimal salinity at 0.5‰ and ceased to grow at 12.8‰ for ammonia oxidation, but remained active for nitrite oxidation. These results show new evidence regarding niche specificity of different nitrifying microorganisms modulated mainly by salinity, and also a clear response by comammoxN. inopinatato a wide range of simulated salinity levels.
