Energetic Diversity in the Electron-Transfer Pathways of Type I Photosynthetic Reaction Centers.

ABSTRACT: Photosynthetic reaction centers from heliobacteria (HbRC) and green sulfur bacteria (GsbRC) are homodimeric proteins and share a common ancestor with photosystem I (PSI), classified as type I reaction centers. Using the HbRC crystal structure, we calculated the redox potential (E_m) values in the electron-transfer branches, solving the linear Poisson-Boltzmann equation and considering the protonation states of all titratable sites in the entire protein-pigment complex. E_m(A_-1) for bacteriochlorophyll g at the secondary site in HbRC (-1157 mV) is as low as E_m(A_-1) for chlorophyll a in PSI (-1173 mV). E_m(A₀/HbRC) is at the same level as E_m(A₀/GsbR

SUBMITTER: Kanda T 

PROVIDER: S-EPMC9949227 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature