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Hopping Maps for Photosynthetic Reaction Centers().

ABSTRACT: Photosynthetic reaction centers (PRCs) employ multiple-step tunneling (hopping) to separate electrons and holes that ultimately drive the chemistry required for metabolism. We recently developed hopping maps that can be used to interpret the rates and energetics of electron/hole hopping in three-site (donor-intermediate-acceptor) tunneling reactions, including those in PRCs. Here we analyze several key ET reactions in PRCs, including forward ET in the L-branch, and hopping that could involve thermodynamically uphill intermediates in the M-branch, which is ET-inactive in vivo. We also explore charge recombination reactions, which could involve hopping. Our hopping maps support the view that electron flow in PRCs involves strong electronic coupling between cofactors and reorganization energies that are among the lowest in biology (? 0.4 eV).

SUBMITTER: Warren JJ

PROVIDER: S-EPMC3530024 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Hopping Maps for Photosynthetic Reaction Centers().

Warren Jeffrey J JJ Winkler Jay R JR Gray Harry B HB

Coordination chemistry reviews 20120714 1

Photosynthetic reaction centers (PRCs) employ multiple-step tunneling (hopping) to separate electrons and holes that ultimately drive the chemistry required for metabolism. We recently developed hopping maps that can be used to interpret the rates and energetics of electron/hole hopping in three-site (donor-intermediate-acceptor) tunneling reactions, including those in PRCs. Here we analyze several key ET reactions in PRCs, including forward ET in the L-branch, and hopping that could involve the ...[more]

PMID: 23275678

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