Synthesis and Reactions of Mo-Fe-S Clusters Toward Understanding of the Mechanism of Nitrogenase

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02733
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 34010:Inorganic/coordination chemistry-related
• Research Institution: Kyoto University (2020-2021); Nagoya University (2019)
• Principal Investigator: Ohki Yasuhiro 京都大学, 化学研究所, 教授 (10324394)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 鉄 / モリブデン / 硫黄 / ニトロゲナーゼ / 窒素固定

Outline of Final Research Achievements

Biological reduction of nitrogen molecule (N2) is mediated by nitrogenaze enzyme, where a complex metal-sulfur cluster designated FeMo-cofactor is used. Despite of studies on the reactions of synthetic Mo-Fe-S clusters over the past nearly half century, activation and conversion of N2 on the Fe sites of Mo-Fe-S clusters remain elusive. In this research project, we synthesized a series of triangular Mo-S clusters as platforms to accommodate chlorides of iron-group metals M. The resultant cubic Mo-M-S clusters were subjected to N2 activation.
We also attempted to apply synthetic Fe-S clusters in biochemical studies, and in collaboration with biochemists, we were able to establish a new protocol to reconstitute proteins with artificial Fe-S clusters. This protocol turned out to be useful to elucidate the biosynthetic pathways of nitrogenase FeMo-cofactor.

Free Research Field

錯体化学、有機金属化学、生物無機化学

Academic Significance and Societal Importance of the Research Achievements

本研究では、ニトロゲナーゼの酵素活性中心FeMo-cofactorに関連深いMo-Fe-Sクラスター錯体を合成し、Feを反応点としてN2を捕捉した。この研究をさらに発展させれば、過去半世紀に渡り検討されてきた一方で誰も実現できていない、金属-硫黄クラスター錯体を触媒とする酵素模倣型のN2還元反応を実現できる可能性があり、さらには酵素機能を超える人工触媒の開発に向けた端緒が拓かれる。