Structural and functional changes associated with heat‐induced phase‐separations of non‐bilayer lipids in chloroplast thylakoid membranes

FEBS Letters

Williams, W.Patrick¹  Quinn, Peter J.²  Brain, Anthony P.R.³  Gounaris, Kleoniki² 

[1] Department of Biophysics, Chelsea College, University of London, Manresa Road, London SW3 6LX, England;Department of Biochemistry, Chelsea College, University of London, Manresa Road, London SW3 6LX, England;Electron Microscope Unit, Chelsea College, University of London, Manresa Road, London SW3 6LX, England

关键词: Chloroplast;    heat stress;    Membrane lipid;    hexagonal phase;    Galactolipid;    Protein-lipid interaction;   

DOI  :  10.1016/0014-5793(83)80117-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The effect of hearing isolated bean chloroplasts on the structure of their thylakoid membranes has been examined by freeze-fracture electron microscopy. A normal morphology of the membranes in which stacked grana can be observed is preserved up to 35°C. Incubation at 35–45°C causes complete destacking of the grana but no alteration in the distribution of the membrane-associated particles between the exoplasmic and protoplasmic fracture faces. Heating above 45°C causes phase-separation of non-bilayer lipids into aggregates of cylindrical inverted micelles. Bleaching experiments show that destacking is associated with disruption of chlorophyll-protein complexes of both photosystems I and II. The rate of electron transport through the photosystems is also perturbed. These results are discussed in terms of the role of non-bilayer lipids in packaging the membrane proteins.

【 授权许可】

Unknown