N 2 O production from hydroxylamine oxidation and corresponding hydroxylamine oxidoreductase involved in a heterotrophic nitrifier A. faecalis strain NR.

Autor: Zhao B; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China., Ran XC; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China., An Q; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China. anqiang@cqu.edu.cn., Huang YS; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China., Lv QH; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China., Dan Q; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
Jazyk: angličtina
Zdroj: Bioprocess and biosystems engineering [Bioprocess Biosyst Eng] 2019 Dec; Vol. 42 (12), pp. 1983-1992. Date of Electronic Publication: 2019 Aug 16.
DOI: 10.1007/s00449-019-02191-w
Abstrakt: N 2 O production from NH 2 OH oxidation involved in a heterotrophic nitrifier Alcaligenes faecalis strain NR was studied. 15 N-labeling experiments showed that biological NH 2 OH consumption by strain NR played a dominant role in N 2 O production, although chemical reaction between NH 2 OH and O 2 indeed existed. Hydroxylamine oxidoreductase (HAO) from strain NR was partially purified by (NH 4 ) 2 SO 4 fractionation and DEAE Cartridge chromatography. The maximum activity of HAO was 9.60 mU with a specific activity of 92.04 mU/(mg protein) when K 3 Fe(CN) 6 was used as an electron acceptor. The addition of Ca 2+ promoted the HAO activity, while the presence of Mn 2+ inhibited the enzyme activity. The optimal temperature and pH for HAO activity were 30 °C and 8. Analysis of enzyme-catalyzed products demonstrated that NH 2 OH oxidation catalyzed by HAO from strain NR played significant role in the production of N 2 O.
Databáze: MEDLINE
Externí odkaz: