The Impact of Carotenoid Energy Levels on the Exciton Dynamics and Singlet-Triplet Annihilation in Isolated Bacterial Light-Harvesting 2 Complexes.

ABSTRACT: The light-harvesting 2 (LH2) complex of purple phototrophic bacteria plays a critical role in absorbing solar energy and distributing the excitation energy. Exciton dynamics within LH2 complexes are controlled by the structural arrangement and energy levels of the bacteriochlorophyll (BChl) and carotenoid (Car) pigments. However, there is still debate over the competing light-harvesting versus energy-dissipation pathways. In this work, we compared five variants of the LH2 complex from genetically modified strains of Rhodobacter sphaeroides, all containing the same BChls but different Cars with increasing conjugation: zeta-carotene (N = 7; LH2_Zeta), neurosporene (N = 9; LH2_Neu), spheroidene (N = 10; LH2_Spher), lycopene (N =

SUBMITTER: Satpathi S 

PROVIDER: S-EPMC12703732 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature