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Function and evolution of grana.

Conrad W Mullineaux
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Abstract

Chloroplasts are descended from cyanobacteria, and they retain many features of the cyanobacterial photosynthetic apparatus. However, land-plant chloroplasts have a strikingly different thylakoid membrane organization to that of cyanobacteria. Usually the two photosystems are laterally segregated; Photosystem II is concentrated in complex stacked-membrane structures known as grana. The function of grana has long been debated. Recent studies on membrane organization in chloroplasts, cyanobacteria and purple bacteria now offer a new perspective. I argue that grana allow the presence of a large light-harvesting antenna for Photosystem II, without excessively restricting electron transport. Other organisms solve this problem in different ways. Land plants evolved from macroalgae that were adapted to high light conditions; they evolved grana as a new solution to the problem of efficient photosynthesis in shade.

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Biological EvolutionChloroplastsCyanobacteriaPhotosynthesisThylakoidsJournal Article

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BibTeXRIS

Conrad W Mullineaux. 2005-10-05. Function and evolution of grana.. https://doi.org/10.1016/j.tplants.2005.09.001

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