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Membrane crystals of plant light-harvesting complex II disassemble reversibly in light.

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 ?CD in granal thylakoids.

SUBMITTER: Hind G

PROVIDER: S-EPMC4184361 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Membrane crystals of plant light-harvesting complex II disassemble reversibly in light.

Hind Geoffrey G Wall Joseph S JS Várkonyi Zsuzsanna Z Istokovics Anita A Lambrev Petar H PH Garab Győző G

Plant & cell physiology 20140503 7

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 f ...[more]

PMID: 24793749

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