| | 2 | Author
| W. S. Cohen, J. R. Barton | Requires cookie* | | | Title
| The Use of 0 2-Evolving Subchloroplast Particles to Study Acceptor and Inhibitor Sites on the Reducing Side of Photosystem II  | | | | Abstract
| Photosystem II particles that retain the ability to evolve 0 2 have been used to exam ine acceptor and inhibitor sites in the photosynthetic electron transfer chain between Q and plasto-quinone. Employing the water to dichlorobenzoquinone reaction to assay photosystem II activity, we have demonstrated that electron transport in thylakoids and particles is equally sensitive to inhibition by D C M U , dinoseb, metribuzin, H Q N O and DBMIB. Based on differential sensitivity to inhibition by D C M U vs. H Q N O or DBMIB, we suggest that when synthetic quinones, e.g. 2,6-dichlorobenzoquinone operate as Hill reagents in particles they are reduced primarily by the plastoquinone pool. W hen synthetic quinones, e.g. 5,6-m ethylenedioxy-2,3-dim ethyl benzoquinone act as autoxidizable acceptors they accept electron from the Q /B com plex at a point that is located between the D C M U and H Q N O (DBM IB) inhibition sites. | | | |
Reference
| Z. Naturforsch. 38c, 793—798 (1983); received April 26 1983 | | | |
Published
| 1983 | | | |
Keywords
| Thylakoids, Photosystem II Particles, Q uinones, Inhibitors, Electron Transfer | | | |
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| | | | | TEI-XML for
| default:Reihe_C/38/ZNC-1983-38c-0793.pdf | | | | Identifier
| ZNC-1983-38c-0793 | | | | Volume
| 38 | |
| 3 | Author
| Z. Naturforsch | Requires cookie* | | | Title
| Herbicide and Plastoquinone Binding to Photosystem II | | | | Abstract
| In plastoquinone-depleted thylakoids "D C M U -typ e" herbicides generally have a lower binding affinity as compared to control thylakoids, with the exception o f D C M U itself. Contrary, binding properties o f phenolic herbicides are not affected by plastoquinone depletion. D C M U in plastoquinone-depleted thylakoids can be displaced from the m em brane by various substituted 1,4-benzoquinones, including plastoquinone-1. Labeling patterns by azido-atrazine are com pared for thylakoids, plastoquinone-depleted thylakoids, and different photosystem II preparations from spinach and Chlamydomonas. Azido-atrazine tags a 3 2 -3 4 kD a protein, which seems to be different from another 3 2 -3 4 kDa protein which is preferentially labeled by a plastoquinone-azide. | | | |
Reference
| Z. Naturforsch. 39c, 393—396 (1984); received N ovem ber 30 1983 | | | |
Published
| 1984 | | | |
Keywords
| Photoaffinity Label, Plastoquinone D epletion, Photosystem II Particles, Chlam ydom onas | | | |
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| | | | | TEI-XML for
| default:Reihe_C/39/ZNC-1984-39c-0393.pdf | | | | Identifier
| ZNC-1984-39c-0393 | | | | Volume
| 39 | |
| 4 | Author
| Matthias Kuhn, Andreas Thiel, Peter Böger | Requires cookie* | | | Title
| The 9-kDa Phosphoprotein Involved in Photoinhibition | | | | Abstract
| Photosystem-II particles exhibit strong photoinhibition. Short-term illumination of photosys-tem-II particles with high-intensity light (5000 piE/m 2 x s) leads to a typical change of the protein pattern on SDS-PAGE. Two proteins are mainly affected, namely the well-described 32-kDa herbicide-binding protein which probably is degraded [1] and, first published here, the 9-kDa phosphoprotein, whose function in the PS-II complex is still unknown. This protein is not de-graded, but seems to be linked to other polypeptides of the PS-II complex. During light treatment new bands of 23, 41, 50 and 54 kDa appear in the protein pattern of SDS-PAGE. A monospecific antiserum was produced against the 9-kDa phosphoprotein to investigate its fate. After light treatment the antibodies reacted with new proteins of higher molecular weights, most pronounced with a 23-kDa and a 41-kDa peptide. | | | |
Reference
| Z. Naturforsch. 43c, 413—417 (1988); received February 15 1988 | | | |
Published
| 1988 | | | |
Keywords
| 9-kDa Phosphoprotein, Photosystem-II Particles, Photoinhibition, Protein Phosphorylation, Antibody | | | |
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| | | | | TEI-XML for
| default:Reihe_C/43/ZNC-1988-43c-0413.pdf | | | | Identifier
| ZNC-1988-43c-0413 | | | | Volume
| 43 | |
| 5 | Author
| J. Bednarz, A. Radunz, G. H. Schmid | Requires cookie* | | | Title
| Lipid Composition of Photosystem I and II in the Tobacco Mutant Nicotiana tabacum NC 95 | | | | Abstract
| The lipids of photosystem II particles, of chloroplasts and leaves are compared in the variegated tobacco mutant NC 95. The mutant differs from other N. tabacum mutants by the phenomenon that it has variegated leaves with green and with yellow-green leaf patches. Chloroplasts from the green leaf areas exhibit photosystem II and photosystem I reactions and have a normal lamellar system with grana and intergrana regions. Chloroplasts from the yellow-green leaf areas, how-ever, yield only photosystem I reactions and have only single stranded isolated thylakoids. Hence, this mutant offers the unique possibility to compare without the use of detergents within the same plant the lipid composition of photosystem II particles with that in intact chloroplasts, exhibiting either photosystem II and I reactions or those exhibiting exclusively photosystem I reactions. The lipids of photosystem II particles are composed of 37% glycolipids, 4% phospholipids, 5% carotenoids and 54% chlorophyll. Lipids of chloroplasts with grana stacking are composed of 75% glycolipids, 7% phospholipids, 2% carotenoids and 16% chlorophyll. Chloroplasts with single isolated thylakoids have a lipid composition consisting of 83% glycolipids, 14% phos-pholipids and only 0.5% carotenoids and 2% chlorophyll. The chloroplast lipid mixture is charac-terized in comparison to the respective leaf lipid mixture by a 16—17% higher glycolipid portion and by a 13-70% lower phospholipid content. The main difference in the lipid composition of photosystem I and II consists in the observation that chloroplasts active in only photosystem I contain more than double the amount of glycolipids and the 4-fold amount of phospholipids in comparison to photosystem II active preparations. The amount of monogalactolipid is even 3 times higher in chloroplasts active only in photosystem I when compared to those in photosystem II particles. In photosystem II particles phosphatidyl-ethanolamine is completely lacking and phosphatidylglycerol and phosphatidylinositol occur only in traces. The fatty acids of the sulfolipid are by 45% more saturated in the photosystem II particles and the digalactolipids of the photosystem II particles are by 28% more saturated than in chloroplasts exhibiting photosystem I and II activity. | | | |
Reference
| Z. Naturforsch. 43c, 423—430 (1988); received March 3 1988 | | | |
Published
| 1988 | | | |
Keywords
| Lipids, Fatty Acids, Chloroplasts, Lipid Asymmetry, Photosystem II Particles | | | |
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| default:Reihe_C/43/ZNC-1988-43c-0423.pdf | | | | Identifier
| ZNC-1988-43c-0423 | | | | Volume
| 43 | |
| 6 | Author
| Chandra Surendra, Subash Sabat3, Prasanna Padhyeb, Mohantyc | Requires cookie* | | | Title
| Inhibitory Effects of Synthetic Lanthanum-Crown Ether at the Reducing Side of Photosystem II | | | | Abstract
| Inhibitory effects of lanthanum-crown [La-(Pic)3 (15-crown-6) 3H2OJ.was investigated on the 0 2 evolution activity of photsystem II particles. Lanthanum (La)-crown inhibited the electron flow at the reducing side of PS II complex. Short duration (1 -2 min) treatment of PS II membranes with trypsin partly developed resistance to La-crown inhibition. However, longer proteolytic treatment (>2 min) appeared to expose newer site(s) for La-crown inhibi tion. The inhibitory constant (K,) for La-crown was nearly 0.17 | j ,m . This inhibitory capacity is about 4 to 5 times less than the potent PS II inhibitor diuron which also binds at the acceptor side of PS II. The number of binding sites for La-crown was found to be 1 per 20 chlorophyll molecules. The Hill plot analysis showed the presence of three distinct straight lines suggesting that the compound acts at least at three sites. Furthermore, from the slope value (Hill coefficient) it is suggested that two of these sites provide minimum of two binding domains for the inhibitor. | | | |
Reference
| Z. Naturforsch. 53c, 49 (1998); received June 16/September 29 1997 | | | |
Published
| 1998 | | | |
Keywords
| Beta vulgaris, Electron Transport Inhibition, Lanthanum Crown, Photosystem II Particles | | | |
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| default:Reihe_C/53/ZNC-1998-53c-0049.pdf | | | | Identifier
| ZNC-1998-53c-0049 | | | | Volume
| 53 | |
| 7 | Author
| SurendraC. Handra Sabat | Requires cookie* | | | Title
| Copper Ion Inhibition of Electron Transport Activity in Sodium Chloride Washed Photosystem II Particle Is Partially Prevented by Calcium Ion | | | | Abstract
| The inhibitory effects of copper ion (Cu2+) on the photosynthetic electron transport func tion was investigated both in NaCl washed (depleted in 17 and 23 kDa polypeptides) and native (unwashed) photosystem II membrane preparations from spinach (Beta vulgaris) chlo-roplasts. Copper in the range of 2.0 to 15 j im strongly inhibited the electron flow from water to 2,6-dichlorobenzoquinone in NaCl washed particles in a concentration dependent manner. Com plete inhibition was noticed at 15 [.im Cu2+. Oppositely in native membranes, 15 (.im C u2+ inhibited only 10-12% o f control activity. It was found that calcium ion (Ca2+) significantly reduced the Cu2+ inhibition o f electron transport activity. The Ca2+ supported prevention of Cu2+ toxicity was specific to Ca2+. Further analysis indicated that both Cu2+ and Ca2+ act competitively. Since Ca2+ is known to have stimulating/stabilizing effect at the donor side of photosystem II, it is therefore suggested that Cu2+ in NaCl washed particles exerts its inhibi tory effect(s) at the oxidizing side of photosystem stim ulates/stabilizes the oxygen evolution. | | | |
Reference
| Z. Naturforsch. 51c, 179—1 (1996); received September 26 1995 | | | |
Published
| 1996 | | | |
Keywords
| Calcium Ion Copper Inhibition, Electron Transport, Photosystem II Particles, Spinach (Beta vulgaris) | | | |
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| | | | | TEI-XML for
| default:Reihe_C/51/ZNC-1996-51c-0179.pdf | | | | Identifier
| ZNC-1996-51c-0179 | | | | Volume
| 51 | |
| 8 | Author
| Gerhard Herrmann, Andreas Thiel, Peter Böger | Requires cookie* | | | Title
| Antiserum Against the 33-kDa Herbicide-Binding Protein | | | | Abstract
| A rabbit antiserum was prepared against the purified 33-kDa herbicide-binding protein (HBP) from the alga Bumilleriopsis filiformis. Specificity at 1:10,000 dilution (v/v) of the unpurified serum is detectable in the immunoblotting assay with both the 33-kDa protein from the alga Bumilleriopsis as well as that from Spinacia. Agglutination can be observed with photosystem-II particles only, not with intact thylakoids, indicative of a hidden location of the protein determi nants in the membrane. Neither herbicide binding nor electron transport is influenced by the antibody. Apparently, the antigenic site of the HBP for the antibody used here is different from the herbicide-binding region. | | | |
Reference
| Z. Naturforsch. 40c, 814 (1985); received August 9 1985 | | | |
Published
| 1985 | | | |
Keywords
| Photosystem-II Particles, Immunoblotting, Antibody Agglutination, Cross Reaction, Urea-Gradient Gel Electrophoresis | | | |
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| default:Reihe_C/40/ZNC-1985-40c-0814.pdf | | | | Identifier
| ZNC-1985-40c-0814 | | | | Volume
| 40 | |
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