Abstract
Extraction of thylakoid membranes with cholate in the presence of ammonium sulfate inactivated oxygen evolution and liberated a managanese-containing protein. This protein could be combined with preformed liposomes containing the depleted thylakoid membranes to restore 85% of the original oxygen-evolution activity. The protein did not affect the primary photochemical events of photosystem I or photosystem II, and it was required only for electron transport in which water was the electron donor. The protein has been purified to homogeneity and has an apparent molecular weight of 65,000 (polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate). Atomic absorption revealed two atoms of manganese bound to each 65,000-dalton protein molecule. Treatment with alkaline Tris removed the bound manganese and rendered the protein incapable of restoring oxygen evolution; however, Tris treatment of the depleted membranes before reconstitution had no effect. Thus, this manganese protein is probably the site of Tris action in isolated chloroplasts and is at least part of the water-oxidation enzyme system.
Keywords: photosystem II, spinach chloroplast, water oxidation
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- Arnon D. I. COPPER ENZYMES IN ISOLATED CHLOROPLASTS. POLYPHENOLOXIDASE IN BETA VULGARIS. Plant Physiol. 1949 Jan;24(1):1–15. doi: 10.1104/pp.24.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blankenship R. E., Sauer K. Manganese in photosynthetic oxygen evolution. I. Electron paramagnetic resonance study of the environment of manganese in Tris-washed chloroplasts. Biochim Biophys Acta. 1974 Aug 23;357(2):252–266. doi: 10.1016/0005-2728(74)90065-6. [DOI] [PubMed] [Google Scholar]
- Cheniae G. M., Martin I. F. Photoactivation of the manganese catalyst of O 2 evolution. I. Biochemical and kinetic aspects. Biochim Biophys Acta. 1971 Nov 2;253(1):167–181. doi: 10.1016/0005-2728(71)90242-8. [DOI] [PubMed] [Google Scholar]
- Cheniae G. M., Martin I. F. Sites of function of manganese within photosystem II. Roles in O2 evolution and system II. Biochim Biophys Acta. 1970 Mar 3;197(2):219–239. doi: 10.1016/0005-2728(70)90033-2. [DOI] [PubMed] [Google Scholar]
- Cheniae G. M., Martin I. F. Studies on the function of manganese in photosynthesis. Brookhaven Symp Biol. 1966;19:406–417. [PubMed] [Google Scholar]
- Chua N. H., Bennoun P. Thylakoid membrane polypeptides of Chlamydomonas reinhardtii: wild-type and mutant strains deficient in photosystem II reaction center. Proc Natl Acad Sci U S A. 1975 Jun;72(6):2175–2179. doi: 10.1073/pnas.72.6.2175. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kok B., Forbush B., McGloin M. Cooperation of charges in photosynthetic O2 evolution-I. A linear four step mechanism. Photochem Photobiol. 1970 Jun;11(6):457–475. doi: 10.1111/j.1751-1097.1970.tb06017.x. [DOI] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Racker E. A new procedure for the reconstitution of biologically active phospholipid vesicles. Biochem Biophys Res Commun. 1973 Nov 1;55(1):224–230. doi: 10.1016/s0006-291x(73)80083-x. [DOI] [PubMed] [Google Scholar]
- Radmer R., Cheniae G. M. Photoactivation of the manganese catalyst of 0 2 evolution II. A two-guantum mechanism. Biochim Biophys Acta. 1971 Nov 2;253(1):182–186. doi: 10.1016/0005-2728(71)90243-x. [DOI] [PubMed] [Google Scholar]
- Stillwell W., Tien H. T. Oxygen evolution from broken thylakoids fused with liposomes. Biochem Biophys Res Commun. 1978 Mar 15;81(1):212–216. doi: 10.1016/0006-291x(78)91651-0. [DOI] [PubMed] [Google Scholar]
- Winget G. D., Kanner N., Racker E. Formation of ATP by the adenosine triphosphatase complex from spinach chloroplasts reconstituted together with bacteriorhodopsin. Biochim Biophys Acta. 1977 Jun 9;460(3):490–499. doi: 10.1016/0005-2728(77)90087-1. [DOI] [PubMed] [Google Scholar]
- Yamashita T., Butler W. L. Inhibition of the Hill Reaction by Tris and Restoration by Electron Donation to Photosystem II. Plant Physiol. 1969 Mar;44(3):435–438. doi: 10.1104/pp.44.3.435. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yamashita T., Butler W. L. Photoreduction and photophosphorylation with tris-washed chloroplasts. Plant Physiol. 1968 Dec;43(12):1978–1986. doi: 10.1104/pp.43.12.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]