2015 Fiscal Year Final Research Report
Emission of nitrous oxide from marine ammonia-oxidizing bacterium
Project/Area Number |
25340006
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Environmental dynamic analysis
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Research Institution | Shizuoka University |
Principal Investigator |
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Project Period (FY) |
2013-04-01 – 2016-03-31
|
Keywords | 硝化 / アンモニア酸化細菌 / 亜酸化窒素 / 温室効果ガス / ヒドロキシルアミン酸化還元酵素 / 従属栄養的硝化 |
Outline of Final Research Achievements |
Aim of this project is to clarify biochemical process of nitrous oxide (N2O) emission by nitrifying microorganisms. In this project, generation of N2O as a by-product of hydroxylamine oxidoreductase (HAO) reaction was proved by using the enzyme purified from marine ammonia-oxidizing bacterium (AOB), Nitrosococcus oceani. Kinetic analysis of the HAO reaction was carried out. Construction of HAO expression system has also been attempted. Because unique chemical modification is essential for maturation of HAO, new expression system is now preparing by utilizing another AOB as the host cells. Biochemical analysis of heterotrophic nitrification was also started in this project. Pyruvic oxime dioxygenase (POD) was purified from Alcaligenes faecalis. Surprisingly, POD was a homologous enzyme to class II aldolase. This finding may give new perspectives not only in the biochemistry of heterotrophic nitrification but also in the catalytic mechanism of oxygenase.
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Free Research Field |
環境微生物生化学
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