Low unsaturation level of thylakoid membrane lipids limits turnover of the D1 protein of photosystem II at high irradiance.
Turnover of the D1 protein of photosystem II (PSII) was studied in mutants of Synechocystis sp. PCC 6803 defective in the desaturation of thylakoid membrane lipids. The lack of polyunsaturated fatty acids from membranes made PSII extremely susceptible to photoinhibition and caused a significant reduction in the D1 protein content of the thylakoid membranes at high irradiances. These results may be attributed to an impaired function in the protein synthesis machinery, most probably at the translational or posttranslational level.
Kanervo
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E
Department of Biology, University of Turku, Finland.
Aro
E M
EM
Murata
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N
D002736:Chloroplasts / Q000378:metabolism / Q000528:radiation effects; D000458:Cyanobacteria / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects*; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism / Q000528:radiation effects; D008027:Light; D008563:Membrane Lipids / Q000737:chemistry / Q000378:metabolism*; D009154:Mutation; D010777:Photochemistry; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects*; D045332:Photosystem II Protein Complex; D014158:Transcription, Genetic
D005231:Fatty Acids, Unsaturated; D008563:Membrane Lipids; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex