The structure of a red-shifted photosystem I reveals a red site in the core antenna.

ABSTRACT: Photosystem I coordinates more than 90 chlorophylls in its core antenna while achieving near perfect quantum efficiency. Low energy chlorophylls (also known as red chlorophylls) residing in the antenna are important for energy transfer dynamics and yield, however, their precise location remained elusive. Here, we construct a chimeric Photosystem I complex in Synechocystis PCC 6803 that shows enhanced absorption in the red spectral region. We combine Cryo-EM and spectroscopy to determine the structure^-function relationship in this red-shifted Photosystem I complex. Determining the structure of this complex reveals the precise architecture of the low energy site as well as large scale structural heterogeneity which is probably universal to all trimeric Photosystem I complexes. Ide

SUBMITTER: Toporik H 

PROVIDER: S-EPMC7573975 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature