Prominent Role of Charge Transfer in the Spectral Tuning of Photosynthetic Light-Harvesting I Complex.

ABSTRACT: Purple bacteria possess two ring-shaped protein complexes, light-harvesting 1 (LH1) and 2 (LH2), both of which function as antennas for solar energy utilization for photosynthesis but exhibit distinct absorption properties. The two antennas have differing amounts of bacteriochlorophyll (BChl) a; however, their significance in spectral tuning remains elusive. Here, we report a high-precision evaluation of the physicochemical factors contributing to the variation in absorption maxima between LH1 and LH2, namely, BChl a structural distortion, protein electrostatic interaction, excitonic coupling, and charge transfer (CT) effects, as derived from detailed spectral calculations using an extended version of the exciton model, in the model purple bacterium Rhodospirillum rubrum</

SUBMITTER: Fujimoto KJ 

PROVIDER: S-EPMC11428290 | biostudies-literature | 2024 Sep

REPOSITORIES: biostudies-literature