Resolving the structure of the E₁ state of Mo nitrogenase through Mo and Fe K-edge EXAFS and QM/MM calculations.

ABSTRACT: Biological nitrogen fixation is predominately accomplished through Mo nitrogenase, which utilizes a complex MoFe₇S₉C catalytic cluster to reduce N₂ to NH₃. This cluster requires the accumulation of three to four reducing equivalents prior to binding N₂; however, despite decades of research, the intermediate states formed prior to N₂ binding are still poorly understood. Herein, we use Mo and Fe K-edge X-ray absorption spectroscopy and QM/MM calculations to investigate the nature of the E₁ state, which is formed following the addition of the first reducing equivalent to Mo nitrogenase. By analyzing the extended X-ray absorption fine structure (EXAFS) region, we provide structural insight into the changes that occur

SUBMITTER: Van Stappen C 

PROVIDER: S-EPMC6984330 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature