Microsolvation of the Redox-Active Tyrosine-D in Photosystem II: Correlation of Energetics with EPR Spectroscopy and Oxidation-Induced Proton Transfer.

ABSTRACT: Photosystem II (PSII) of oxygenic photosynthesis captures sunlight to drive the catalytic oxidation of water and the reduction of plastoquinone. Among the several redox-active cofactors that participate in intricate electron transfer pathways there are two tyrosine residues, Y_Z and Y_D. They are situated in symmetry-related electron transfer branches but have different environments and play distinct roles. Y_Z is the immediate oxidant of the oxygen-evolving Mn₄CaO₅ cluster, whereas Y_D serves regulatory and protective functions. The protonation states and hydrogen-bond network in the environment of Y_D remain debated, while the role of microsolvation in stabilizing different redox states of Y_D and facilitat

SUBMITTER: Sirohiwal A 

PROVIDER: S-EPMC6728127 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature