Development of Photosystem II in dark grown Chlamydomonas reinhardtii. A light-dependent conversion of PS II?, QB-nonreducing centers to the PS II?, QB-reducing form
- 1 April 1990
- journal article
- Published by Springer Science and Business Media LLC in Photosynthesis Research
- Vol. 24 (1), 35-46
- https://doi.org/10.1007/bf00032642
Abstract
The green alga Chlamydomonas reinhardtii is a facultative heterotroph and, when cultured in the presence of acetate, will synthesize chlorophyll (Chl) and photosystem (PS) components in the dark. Analysis of the thylakoid membrane composition and function in dark grown C. reinhardtii revealed that photochemically competent PS II complexes were synthesized and assembled in the thylakoid membrane. These PS II centers were impaired in the electron-transport reaction from the primary-quinone electron acceptor, QA, to the secondary-quinone electron acceptor, QB (QB-nonreducing centers). Both complements of the PS II Chl a−b light harvesting antenna (LHC II-inner and LHC II-peripheral) were synthesized and assembled in the thylakoid membrane of dark grown C. reinhardtii cells. However, the LHC II-peripheral was energetically uncoupled from the PS II reaction center. Thus, PS II units in dark grown cells had a β-type Chl antenna size with only 130 Chl (a and b) molecules (by definition, PS IIβ units lack LHC II-peripheral). Illumination of dark grown C. reinhardtii caused pronounced changes in the organization and function of PS II. With a half-time of about 30 min, PS II centers were converted froma QB-nonreducing form in the dark, to a QB-reducing form in the light. Concomitant with this change, PS IIβ units were energetically coupled with the LHC II-peripheral complement in the thylakoid membrane and were converted to a PS IIα form. The functional antenna of the latter contained more than 250 Chl(a+b) molecules. The results are discussed in terms of a light-dependent activation of the QA-QB electron-transfer reaction which is followed by association of the PS IIβ unit with a LHC II-peripheral antenna and by inclusion of the mature form of PS II (PS IIα) in the membrane of the grana partition region.Keywords
This publication has 25 references indexed in Scilit:
- Chlorophyll b deficiency in soybean mutants. I. Effects on photosystem stoichiometry and chlorophyll antenna sizeBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1988
- Compensatory Alterations in the Photochemical Apparatus of a Photoregulatory, Chlorophyll b-Deficient Mutant of MaizePlant Physiology, 1988
- Evidence for slow turnover in a fraction of Photosystem II complexes in thylakoid membranesBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1987
- Photoinhibition: Impairment of the primary charge separation between P‐680 and pheophytin in photosystem II of chloroplastsFEBS Letters, 1987
- Detection of oxygen-evolving Photosystem II centers inactive in plastoquinone reductionBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1986
- Heterogeneity in chloroplast photosystem IIPhotosynthesis Research, 1986
- Localization of different photosystems in separate regions of chloroplast membranesProceedings of the National Academy of Sciences, 1983
- ABSENCE OF OXYGEN‐EVOLVING CAPACITY IN DARK‐GROWN CHLORELLA: THE PHOTO ACTIVATION OF OXYGEN‐EVOLVING CENTERS*Photochemistry and Photobiology, 1973
- Reaction between primary and secondary electron acceptors of Photosystem II of photosynthesisBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1968
- COPPER ENZYMES IN ISOLATED CHLOROPLASTS. POLYPHENOLOXIDASE IN BETA VULGARISPlant Physiology, 1949