Proton transfer during reduction of the catalytic metallo-cofactors of the three nitrogenase isozymes.

ABSTRACT: Nitrogenase catalyzes biological nitrogen fixation, the conversion of atmospheric N₂ into bioavailable ammonia. The three nitrogenase isozymes-Mo-nitrogenase, V-nitrogenase, and Fe-nitrogenase-utilize catalytic cofactors distinguished by their metal composition (Fe₇M, M = Mo, V, or Fe; denoted FeM-co). Their catalytic cycles involve stepwise addition of 8[e^-/H⁺] to FeM-co, generating intermediates designated E _n , where n is the number of [e^-/H⁺] delivered. The electron-transfer has been extensively characterized, but the proton delivery has not. Here, we investigate [e^-/H⁺] delivery during early-stage conversions, primarily E₀ → E₁(H), for each of the thre

SUBMITTER: Davydov R 

PROVIDER: S-EPMC12429461 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature