1. Membrane crystals of plant light-harvesting complex II disassemble reversibly in light.
- Author
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Hind G, Wall JS, Várkonyi Z, Istokovics A, Lambrev PH, and Garab G
- Subjects
- Cations metabolism, Circular Dichroism, Darkness, Hot Temperature, Light, Light-Harvesting Protein Complexes ultrastructure, Magnesium metabolism, Membrane Lipids, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Models, Molecular, Pisum sativum radiation effects, Pisum sativum ultrastructure, Photosystem II Protein Complex chemistry, Photosystem II Protein Complex ultrastructure, Plant Leaves chemistry, Plant Leaves radiation effects, Plant Leaves ultrastructure, Thylakoids ultrastructure, Adaptation, Physiological, Light-Harvesting Protein Complexes chemistry, Pisum sativum chemistry, Thylakoids chemistry
- Abstract
Using the mass-measuring capability of scanning transmission electron microscopy, we demonstrate that membrane crystals of the main light-harvesting complex of plants possess the ability to undergo light-induced dark-reversible disassociations, independently of the photochemical apparatus. This is the first direct visualization of light-driven reversible reorganizations in an isolated photosynthetic antenna. These reorganizations, identified earlier by circular dichroism (CD), can be accounted for by a biological thermo-optic transition: structural changes are induced by fast heat transients and thermal instabilities near the dissipation, and self-association of the complexes in the lipid matrix. A comparable process in native membranes is indicated by earlier findings of essentially identical kinetics, and intensity and temperature dependences of the ΔCD in granal thylakoids., (© The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2014
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