Functional expression of nitrogen fixing enzyme, nitrogenase on higher plants

2019 Fiscal Year Final Research Report

• Project/Area Number: 19K21143
• Project/Area Number (Other): 18H06000 (2018)
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund (2019); Single-year Grants (2018)
• Review Section: 0601:Agricultural chemistry and related fields
• Research Institution: Nagoya University
• Principal Investigator: YAMAMOTO Haruki 名古屋大学, 生命農学研究科, 助教 (80615451)
• Project Period (FY): 2018-08-24 – 2020-03-31
• Keywords: ニトロゲナーゼ

Outline of Final Research Achievements

In this study, we aimed to introduce nitrogenase, an enzyme that reduces molecular nitrogen to ammonia, into higher plants to create a basis for creating crop plants that can fix nitrogen. We searched for the optimal expression site of nitrogenase in plants using the expression of NifH, which is the reducing component of nitrogenase, as an index. Studies up to last year revealed that NifH was successfully expressed locally in chloroplasts, mitochondria, and cytoplasm in plant cells, and that the expression level of NifH was highest in flower stems. In this year, we established a purification method to detect the activity of NifH expressed in plant cells and constructed an in vitro nitrogenase activity assay method.

Free Research Field

生化学、分子生物学

Academic Significance and Societal Importance of the Research Achievements

本研究では分子状窒素をアンモニアへと還元する酵素ニトロゲナーゼを高等植物に導入し、窒素固定可能な作物植物を創り出す基盤を作ることを目指した。ニトロゲナーゼの還元コンポーネントであるNifHの発言を指標に植物体内における最適なニトロゲナーゼの発現部位の探索を行った。本研究では植物体内で発現したNifHの活性の確認はできなかったが、時間的、空間的に分離したサンプリングによって、植物組織内でNIfHの安定性について新たな知見をもたらし、今後の植物体におけるニトロゲナーゼ発現に関する研究の礎となる実績となった。