Structure and biogenesis of Chlamydomonas reinhardtii photosystem I
- 1 November 1988
- journal article
- research article
- Published by Wiley in European Journal of Biochemistry
- Vol. 177 (2), 411-416
- https://doi.org/10.1111/j.1432-1033.1988.tb14389.x
Abstract
The turnover of photosystem-II proteins during photoinhibition was analyzed in the green alga Chlamydomonas reinhardtii. Changes in the amount of photosystem II core complex polypeptides D1, D2, 44 kDa and 51 kDa, the antennae-CP-29 and light-harvesting-complex-II polypeptides and the water-oxidizing complex polypeptides of 30 kDa, 23 kDa and 16 kDa were monitored by a variety of techniques. Only the D1 and D2 polypeptides were found to turnover during photoinhibition when cells were exposed to ten fold photosynthesis-saturating light (2500 W/m2 for 90 min) at 25.degree. C. While 80% of photosystem-II activity was lost, a reduction of only 20% was observed in the total amount of D1 and D2 proteins. However, inhibition of chloroplast translation by chloramphenicol during photoinhibition resulted in the loss of about 60% of the D1 and 40% of the D2 proteins, as demonstrated by Western blotting and dot blotting of isolated thylakoids, quantitative analysis of immunogold-labeled whole-cell thin sections, and chase of radioactively prelabelled proteins during photoinhibition. We propose that the light-dependent turnover of the D1 protein is a protective mechanism against photoinhibition as far as the removal and replacement of D1 is compatible with the photoinactivation incurred by photosystem II. At light intensities at which the rate of D1 removal becomes limiting, loss of photosystem-II activity exceeds the turnover of D1 and the stability of the D2 protein is impaired as well.This publication has 55 references indexed in Scilit:
- Stoichiometry and turnover of photosystem II polypeptidesFEBS Letters, 1987
- Purification and composition of photosystem I reaction center of Prochloron sp., an oxygen‐evolving prokaryote containing chlorophyll bFEBS Letters, 1985
- Isolation of Photosystem I Complexes from Octyl Glucoside/Sodium Dodecyl Sulfate Solubilized Spinach ThylakoidsPlant Physiology, 1985
- The chloroplast 32 kDa protein is synthesized on thylakoid‐bound ribosomes in Chlamydomonas reinhardtiiFEBS Letters, 1985
- Membrane protein damage and repair: removal and replacement of inactivated 32-kilodalton polypeptides in chloroplast membranes.The Journal of cell biology, 1984
- The 77 K fluorescence spectrum of the Photosystem I pigment—protein complex CPIaFEBS Letters, 1984
- Chlorophyll a/b proteins of Photosystem IFEBS Letters, 1984
- Photorespiration and photoinhibitionBiochimica et Biophysica Acta (BBA) - Reviews on Bioenergetics, 1981
- Studies on the Mechanism of Photoinhibition in Higher PlantsPlant Physiology, 1981
- Site of synthesis of subunits to photosystem I reaction center and the proton—ATPase in SpirodelaFEBS Letters, 1981