Energetics and Dynamics of Proton-Coupled Electron Transfer in the NADH/FMN Site of Respiratory Complex I.

ABSTRACT: Complex I functions as an initial electron acceptor in aerobic respiratory chains that reduces quinone and pumps protons across a biological membrane. This remarkable charge transfer process extends ca. 300 Å and it is initiated by a poorly understood proton-coupled electron transfer (PCET) reaction between nicotinamide adenine dinucleotide (NADH) and a protein-bound flavin (FMN) cofactor. We combine here large-scale density functional theory calculations and quantum/classical models with atomistic molecular dynamics simulations to probe the energetics and dynamics of the NADH-driven PCET reaction in complex I. We find that the reaction takes place by concerted hydrogen atom (H^•) transfer that couples to an electron transfer (eT) between the aromatic ring systems of the cofactor

SUBMITTER: Saura P 

PROVIDER: S-EPMC6890364 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature