Huang Yuan Sheng, An Qiang, Zhao Bin, Lv Qing Hao, Guo Jing Song
Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China.
Arch Microbiol. 2018 Jan;200(1):147-158. doi: 10.1007/s00203-017-1428-4. Epub 2017 Sep 6.
The potential for aerobic NO removal by Alcaligenes faecalis strain NR was investigated. 35 mg/L of NO-N was removed by strain NR under aerobic conditions in the presence of NH. N-labeling experiment demonstrated that NO and N were possible products during the aerobic nitrite removal process by strain NR. The key enzyme genes of nirK, norB and nosZ, which regulate the aerobic nitrite denitrification process, were successfully amplified from strain NR. The gene sequence analysis indicates that copper-containing nitrite reductase (NIRK) and periplasmic nitrous oxide reductase (NOSZ) were both hydrophilic protein and the transmembrane structures were absent, while nitric oxide reductase large subunit (NORB) was a hydrophobic and transmembrane protein. According to the three-dimensional structure and binding site analysis, the bulky and hydrophobic methionine residue proximity to the nitrite binding sites of NIRK was speculated to be related to the oxygen tolerance of NIRK from strain NR.
研究了粪产碱杆菌菌株NR在有氧条件下去除NO的潜力。在有氧条件下，菌株NR在有NH存在的情况下去除了35 mg/L的NO-N。N标记实验表明，NO和N可能是菌株NR在有氧去除亚硝酸盐过程中的产物。成功从菌株NR中扩增出调控有氧亚硝酸盐反硝化过程的关键酶基因nirK、norB和nosZ。基因序列分析表明，含铜亚硝酸盐还原酶（NIRK）和周质氧化亚氮还原酶（NOSZ）均为亲水蛋白，不存在跨膜结构，而一氧化氮还原酶大亚基（NORB）是一种疏水跨膜蛋白。根据三维结构和结合位点分析，推测靠近NIRK亚硝酸盐结合位点的大的疏水甲硫氨酸残基与菌株NR中NIRK的耐氧性有关。
