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Updated: Jul 16, 2025

Purification of Active Photosystem I-Light Harvesting Complex I from Plant Tissues
Published on: February 3, 2023
Spillover in the direct-type PSI-PSII megacomplex isolated from Arabidopsis thaliana is regulated by pH
Makio Yokono1, Chiyo Noda2, Jun Minagawa1
1Division of Environmental Photobiology, National Institute for Basic Biology, Okazaki, Japan; Basic Biology Program, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Japan.
Abstract:
Various megacomplexes in which Photosystem I and Photosystem II are physically bound (PSI-PSII m.c.) have been found in many organisms. In terms of function, these can be divided into two groups: those in which PSII and PSI are closely coupled (direct-type, photoprotection), and those in which a large light-harvesting antenna is placed between PSII and PSI (bridged-type, energy sharing). Arabidopsis thaliana has been reported to use the direct-type, where fast energy transfer occurs from PSII to PSI (~20 ps, fast spillover). In this paper, we show that the fast spillover is reversibly regulated depending on pH.
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