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Van Ginkel G. AGEING OF ISOLATED CHLOROPLASTS IN A STABILIZING MEDIUM: INFLUENCE OF DIFFERENT TYPES OF PHOTOPHOSPHORYLATION*. ACTA ACUST UNITED AC 2015. [DOI: 10.1111/j.1438-8677.1977.tb01120.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- G. Van Ginkel
- Vakgroep Biofysica, Laboratorium voor Experimentele Fysica; Utrecht
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von Berlepsch S, Kunz HH, Brodesser S, Fink P, Marin K, Flügge UI, Gierth M. The acyl-acyl carrier protein synthetase from Synechocystis sp. PCC 6803 mediates fatty acid import. PLANT PHYSIOLOGY 2012; 159:606-17. [PMID: 22535424 PMCID: PMC3375928 DOI: 10.1104/pp.112.195263] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 04/22/2012] [Indexed: 05/21/2023]
Abstract
The transfer of fatty acids across biological membranes is a largely uncharacterized process, although it is essential at membranes of several higher plant organelles like chloroplasts, peroxisomes, or the endoplasmic reticulum. Here, we analyzed loss-of-function mutants of the unicellular cyanobacterium Synechocystis sp. PCC 6803 as a model system to circumvent redundancy problems encountered in eukaryotic organisms. Cells deficient in the only cytoplasmic Synechocystis acyl-acyl carrier protein synthetase (SynAas) were highly resistant to externally provided α-linolenic acid, whereas wild-type cells bleached upon this treatment. Bleaching of wild-type cells was accompanied by a continuous increase of α-linolenic acid in total lipids, whereas no such accumulation could be observed in SynAas-deficient cells (Δsynaas). When SynAas was disrupted in the tocopherol-deficient, α-linolenic acid-hypersensitive Synechocystis mutant Δslr1736, double mutant cells displayed the same resistance phenotype as Δsynaas. Moreover, heterologous expression of SynAas in yeast (Saccharomyces cerevisiae) mutants lacking the major yeast fatty acid import protein Fat1p (Δfat1) led to the restoration of wild-type sensitivity against exogenous α-linolenic acid of the otherwise resistant Δfat1 mutant, indicating that SynAas is functionally equivalent to Fat1p. In addition, liposome assays provided direct evidence for the ability of purified SynAas protein to mediate α-[(14)C]linolenic acid retrieval from preloaded liposome membranes via the synthesis of [(14)C]linolenoyl-acyl carrier protein. Taken together, our data show that an acyl-activating enzyme like SynAas is necessary and sufficient to mediate the transfer of fatty acids across a biological membrane.
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Meunier CF, Van Cutsem P, Kwon YU, Su BL. Thylakoids entrapped within porous silica gel: towards living matter able to convert energy. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b817172f] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Energy from photobioreactors: Bioencapsulation of photosynthetically active molecules, organelles, and whole cells within biologically inert matrices. PURE APPL CHEM 2008. [DOI: 10.1351/pac200880112345] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Photosynthesis is a highly efficient solar energy transformation process. Exploiting this natural phenomenon is one way to overcome the shortage in the Earth’s fuel resources. This review summarizes the work carried out in the field of photobioreactor design via the immobilization of photosynthetically active matter within biologically inert matrices and the potential biotechnological applications of the obtained hybrid materials within the domain of solar energy to chemical energy transformation. The first part deals with the design of artificial photosynthetic reaction centers (RCs) by the encapsulation of pigments, proteins, and complexes. The action of thylakoids, chloroplasts, and whole plant cells, immobilized in biocompatible supports, in the conversion of CO2 into chemical energy, is also addressed. Finally, the latest advances in the exploitation of the bioactivity of photosynthetically active micro-organisms are explored in terms of the production of secondary metabolites and hydrogen.
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The phospholipid population which sustains the uncoupled non-cyclic electron flow activity is localized in the inner monolayer of the thylakoid membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1989. [DOI: 10.1016/s0005-2728(89)80207-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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6
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Siegenthaler PA, Smutny J, Rawyler A. Involvement of distinct populations of phosphatidylglycerol and phosphatidylcholine molecules in photosynthetic electron-flow activities. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1987. [DOI: 10.1016/0005-2728(87)90086-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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7
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Larreta-Garde V, Thomas D. Factors controlling initial and long-term ATP regeneration catalyzed by immobilized chromatophores. Biotechnol Bioeng 1987; 29:79-84. [DOI: 10.1002/bit.260290112] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kaniuga Z, Gemel J, Zablocka B. Fatty-acid-induced release of manganes from chloroplasts. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90116-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Thomasset B, Barbotin JN, Thomas D. The effects of high concentrations of salts on photosynthetic electron transport of immobilized thylakoids: Functional stability. Appl Microbiol Biotechnol 1984. [DOI: 10.1007/bf00454375] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Effect of 6-Benzyl Aminopurine on the Stabilization of Absorption Spectrum and Hill Activity of Isolated Chloroplasts. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/s0015-3796(82)80017-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Morris P, Nash GV, Hall DO. The stability of electron transport in in vitro chloroplast membranes. PHOTOSYNTHESIS RESEARCH 1982; 3:227-240. [PMID: 24458288 DOI: 10.1007/bf00032259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/1981] [Revised: 05/15/1982] [Indexed: 06/03/2023]
Abstract
The stability and stabilization of the electron transport system of chloroplast membranes under physiological conditions of temperature and illumination were studied in relation to two separate and often competing mechanisms of decay. Photochemical inactivation (photoinhibition) of the electron transport system of ageing spinach chloroplasts was not normally found to limit stability even at saturating light intensities. Only when the membranes were protected from dark (fatty acid) inhibition did photoinhibition limit stability.Electron transport could be partially protected from dark inhibition by the addition of high concentrations of recrystallized (i.e. fatty acid free) bovine serum albumin, ovalbumin, polyethyleneimine cellulose, Biomesh SM2 beads or with Ficoll 400. Some improvement in stability was achieved with N,N, dimethylphenethylamine but other esterase and phospholipase inhibitors were ineffective in preventing thermal inactivation.Photoinhibition was apparently delayed by phenazine methosulphate under certain conditions but was unaffected either by artificial scavengers of reactive oxygen species (butylated hydroxytoluene), and 1,4-diazobycyclo (2, 2, 2 octane) or by natural scavengers which constitute part of the in vivo protective mechanism (α-tocopherol, β-carotene, SOD, catalase and glutathione) or by anaerobic incubation. Photoinhibition may therefore be by a separate mechanism which does not initially involve free radical damage.
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Affiliation(s)
- P Morris
- Department of Plant Sciences, University of London King's College, 68 Half Moon Lane, SE24 9JF, London, England
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Cocquempot MF, Thomasset B, Barbotin JN, Gellf G, Thomas D. Comparative stabilization of biological photosystems by several immobilization procedures. ACTA ACUST UNITED AC 1981. [DOI: 10.1007/bf00505866] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Rawyler A, Siegenthaler PA. Role of lipids in functions of photosynthetic membranes revealed by treatment with lipolytic acyl hydrolase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1980; 110:179-87. [PMID: 7439157 DOI: 10.1111/j.1432-1033.1980.tb04853.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
1. Thylakoid membranes and subchloroplast particles I and II enriched in photosystem I and photosystem II, respectively, were treated with a potato lipolytic acyl hydrolase. 2. In the thylakoid membrane fraction, this treatment inhibited electron flows involving both photosystems and the associated photophosphorylations. However, electron flows involving either photosystem I or photosystem II were still preserved. The treatment of thylakoid membranes by lipolytic acyl hydrolase brought about a temporal convergence of different events such as maximal activity of reduced dichloroindophenol-supported electron flows, complete inhibition of photophosphorylations and electron transport activities through photosystem II + I, onset of the decay N,N,N',N-tetramethyl-rho-phenylenediamine-supported activity of photosystem activity and of the stimulation of photosystem activity (from reduced dichloroindophenol to NADP+ by exogenous plastocyanin. 3. Lipolytic acyl hydrolase catalyzed a limited hydrolysis of each lipid but in a stepwise manner, the galactolipids being attacked before the ionic lipids. The extent of the hydrolysis was not more than 50% for each lipid. Most of the hydrolytic process occurred before any significant change in photochemical activities could be observed. 4. In subchloroplast particles I, a treatment by lipolytic acyl hydrolase did not greatly affect the electron transport whilst lipid hydrolysis was almost complete. 5. In subchloroplast particles II, neither the electron flow activities nor lipid content were significantly altered by lipolytic acyl hydrolase. 6. The sites of lipolytic acyl hydrolase action appeared to be localized between plastoquinones and P700. It is suggested that it is not possible to establish a quantitative and/or temporal correlation between the extent of lipid hydrolysis and the inhibition of photochemical activities. 7. The profile of the hydrolysis of lipids in thylakoid membranes suggests that ionic lipids are less accessible to lipolytic acyl hydrolase than galactolipids.
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Loss of hill activity in isolated chloroplasts is not directly related to free fatty acid release during ageing. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0304-4211(80)90007-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Ginkel GV, Hammans JWK. ACTION SPECTRA OF PHOTOPHOSPHORYLATION–I. ATP FORMATION COUPLED TO NON-CYCLIC ELECTRON FLOW. Photochem Photobiol 1980. [DOI: 10.1111/j.1751-1097.1980.tb02556.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Cole RM, Macpeek WA, Cohen WS. Divalent cations and restoration of electron transport activity in fatty acid-treated choloroplasts. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0304-4211(80)90167-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Michalski WP, Kaniuga Z. Photosynthetic apparatus in chilling-sensitive plants. VII. Comparison of the effect of galactolipase treatment of chloroplasts and cold-dark storage of leaves on photosynthetic electron flow. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 589:84-99. [PMID: 7356980 DOI: 10.1016/0005-2728(80)90134-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
1. Both galactolipase treatment of tomato chloroplasts and the cold and dark storage of leaves induce a large degradation of chloroplast monogalactosyl diacylglycerol and digalactosyl diacylglycerol as well as an accumulatwon of free fatty acids accompanied by the inhibition of Hill reaction activity with water as electron donor. All these changes are reversed upon illumination of the leaves. 2. Inhibition of diphenylcarbazide (DPC) leads to dichlorophenolindophenol (DCIP) activity by free fatty acids released following galactolipase treatment of chloroplasts isolated from either fresh or cold and dark-stored and illuminated leaves is almost completely reversed by either bovine serum albumin or Mn2+, while that in chloroplasts from the cold and dark-stored leaves is reversed by bovine serum albumin and Mn2+ only up to about 60 and 25%, respectively. 3. Fatty acids released during the treatment of chloroplasts with galactolipase affect the electron transport mainly in the same site as exogenous unsaturated fatty acids do, while those released due to endogenous galactolipase activity appear to affect also in the region damaged by either Tris washing of chloroplasts or the cold and dark treatment of leaves. 4. The loss of manganese from chloroplasts (Kaniuga, Z., Zabek, J. and Sochanowicz, B. (1978) Planta 144, 49-56) seems to be the main reason of cold and dark-induced inactivation of Hill reaction activity in chloroplasts of chilling-sensitive plants, while both the degradation of galactolipids and the accumulation of fatty acids are of secondary importance.
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[58] Stabilization of chloroplasts and subchloroplast particles. Methods Enzymol 1980. [DOI: 10.1016/s0076-6879(80)69060-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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20
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A Role for Abscisic Acid in Drought Endurance and Drought Avoidance. PROCEEDINGS IN LIFE SCIENCES 1980. [DOI: 10.1007/978-3-642-67720-5_24] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Halliwell B. The chloroplast at work. A review of modern developments in our understanding of chloroplast metabolism. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1979; 33:1-54. [PMID: 415334 DOI: 10.1016/0079-6107(79)90024-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Kaniuga Z, Michalski W. Photosynthetic apparatus in chilling-sensitive plants : II. Changes in free fatty acid composition and photoperoxidation in chloroplasts following cold storage and illumination of leaves in relation to Hill reaction activity. PLANTA 1978; 140:129-136. [PMID: 24414468 DOI: 10.1007/bf00384911] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/1977] [Accepted: 12/30/1977] [Indexed: 06/03/2023]
Abstract
The composition of free fatty acids (FFA) in relation to Hill reaction activity and photoperoxidation of lipids was studied in chloroplasts isolated from fresh, cold and dark-stored as well as illuminated leaves of Lycopersicon esculentum Mill., Phaseolus vulgaris L. and Cucumis sativus L. Following the cold and dark-storage of leaves the loss of Hill reaction activity is accompanied by approximately a 5-fold increase in the amount of FFA and by an increase in the percentage of unsaturated FFA, particularly that of linolenic acid. Illumination of the cold- and dark-stored leaves restores both Hill reaction activity and the content and composition of chloroplast FFA. Following the second and third cycles of cold storage and illumination of leaves the percentage of unsaturated fatty acids in chloroplasts increases while that of saturated ones decreases despite of the significant restoration of Hill reaction activity. Since the illumination of cold-stored leaves results in peroxidation of inhibitory fatty acids it seems likely that this phenomenon could, at least partially, be responsible for the restoration of Hill reaction activity. Inhibition of Hill reaction activity by exogenous linolenic acid in chloroplasts of fresh, cold-stored as well as cold-stored and illuminated leaves could be reversed following the incubation of chloroplast suspension with BSA, however only to a value measured in the absence of unsaturated fatty acid. All these results indicate that the inhibition of Hill reaction activity due to the cold and dark storage of leaves is caused by both inhibitory FFA released from chloroplast lipids as well as by damage to the thylakoid structure affecting the electron transport within photosystem II.
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Affiliation(s)
- Z Kaniuga
- Institute of Biochemistry, University of Warsaw, Al. Zwirki i Wigury 93, 02-089, Warszawa, Poland
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Kaniuga Z, Sochanowicz B, Zabek J, Krystyniak K. Photosynthetic apparatus in chilling-sensitive plants : I. Reactivation of hill reaction activity inhibited on the cold and dark storage of detached leaves and intact plants. PLANTA 1978; 140:121-128. [PMID: 24414467 DOI: 10.1007/bf00384910] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/1977] [Accepted: 12/30/1977] [Indexed: 06/03/2023]
Abstract
Chloroplast isolated from the detached leaves of chilling-sensitive plants-Phaseolus vulgaris L., Cucumis sativus L., and Lycopersicon esculentum Mill.-stored in the cold for 2-4 days in the dark exhibit an almost complete loss of Hill reaction activity, which on illumination of leaves is restored to almost the original level. In contrast, illumination of either chloroplast suspensions or homogenates from leaves stored in the cold in the dark does not cause restoration of electron transport. Cold and dark storage of leaves of chilling-sensitive plants affects the electron transport before the site of electron donation by diphenylcarbazide and results in an increased sensitivity of the Hill reaction of isolated chloroplasts to exogenous linolenic acid. Illumination of leaves reverses these processes. When tomato plants are exposed to 0°C in intermittent light, Hill reaction activity is not affected while dark storage either at 0°C or 25°C results in a significant decrease of Hill reaction activity after 2-3 days followed by the restoration of electron transport to the original level after 1 or 2 days of the prolonged dark storage of plants. When tomato plants are stored either at 0°C in intermittent light, at 0°C in dark, or at 25°C in dark the sensitivity of the Hill reaction to exogenous linolenic acid remains increased despite a significant restoration of this activity. In conclusion, both darkness and the detachment of leaves from the plant are more effective than cold treatment in damaging photosystem II whereas both light and intact structure of the cell are required for restoration of Hill reaction activity in chloroplasts following cold and dark storage of detached leaves.
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Affiliation(s)
- Z Kaniuga
- Institute of Biochemistry, University of Warsaw, Al. Zwirki i Wigury 93, 02-089, Warszawa, Poland
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Aging of the photosynthetic apparatus V. Change in pH dependence of electron transport and relationships to endogenous free fatty acids. ACTA ACUST UNITED AC 1977. [DOI: 10.1016/0304-4211(77)90036-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Terpstra W. Chlorophyllase and Lamellar Structure in Phaeodactylum tricornutum III. Situation of Chlorophyllase in Pigmented Membranes. ACTA ACUST UNITED AC 1976. [DOI: 10.1016/s0044-328x(76)80154-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2022]
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Siegenthaler PA, Depéry F. Influence of unsaturated fatty acids in chloroplasts. Shift of the pH optimum of electron flow and relations to deltapH, thylakoid internal pH and proton uptake. EUROPEAN JOURNAL OF BIOCHEMISTRY 1976; 61:573-80. [PMID: 2470 DOI: 10.1111/j.1432-1033.1976.tb10052.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Linolenic acid (C18:3) is the main endogenous unsaturated fatty acid of thylakoid membrane lipids, and seems in its free form to exert significant effects on the structure and function of photosynthetic membranes. In this investigation the effect of linolenic acid was studied at various pH values on the electron flow rate in isolated spinach chloroplasts and related to deltapH, the proton pump and the pH of the inner thylakoid space (pHi). The deltapH and pHi were estimated from the extent of the fluorescence quenching of 9-aminoacridine. Linolenic acid caused a shift (approximately one unit) of the pH optimum for electron flow toward acidity in the following systems: (a) photosystems II + I (from H2O to NADP+ or to 2,6-dichlorophenolindophenol) coupled or non-coupled; (b) photosystem II (from H2O to 2,6-dichlorophenolindophenol in the presence of dibromothymoquinone). In photosystem I conditions (phenazine methosulphate), the deltapH of the control increased as a function of external pHo with a maximum around pH 8.8. When linolenic acid was added, the deltapH dropped, but its optimum was shifted toward more acidic pHo. The same phenomena were also observed in photosytems II + I (from H2O to ferricyanide) and in photosystem II conditions (from H2O to ferricyanide in the presence of dibromothymoquinone). However, the deltapH was smaller and the sensitivity of the proton gradient toward linolenic acid was eventually higher than for photosystem I electron flow activity. The proton pump which might be considered as a measure of the internal buffering capacity of thylakoids was optimum at pHo, 6.7 in the controls. An addition of linolenic acid diminished the proton pump and shifted its optimum toward higher pHo. As a consequence, pHi increased when pHo was raised. At the optimal pHo 8.6 to 9, pHi were 5 to 5.5. Additions of increasing concentrations of linolenic acid displaced the curves toward higher pHi. A decrease of pHo was therefore required to maintain the pHi in the range of 5-5.5 for maximum electron flow. In conclusion, the electron flow activity seems to be delicately controlled by the proton pump (buffer capacity), deltapH, pHi and pHo. Fatty acids damage the membrane integrity in such a way that the subtile equilibrium between the factors is disturbed.
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Uhrig H, Tevini M. [The effect of phospholipase D on photochemical activity and lipid composition of isolated spinach chloroplasts]. PLANTA 1976; 128:173-178. [PMID: 24430694 DOI: 10.1007/bf00390320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/1975] [Accepted: 10/01/1975] [Indexed: 06/03/2023]
Abstract
Phospholipase D shows short and longtime effects on photochemical activity of isolated spinach chloroplasts. After very short incubations with Phospholipase D (Pl D) the Ferricyanide reduction and Dichlorphenol-idenophenol reduction are 70% to 90% higher than in control chloroplasts. In uncoupled chloroplasts the reduction rates are about 20% higher than in the controls. After one h of incubation time with Phospholipase D the photochemical activity is inhibited and now shows only 40% of the control activity. The effect of Phospholipase D on uncoupled chloroplasts is somewhat lower. After two h of incubation time the control activity decreases to about 50% whereas the PLD-effected activity is reduced to 10% of the initial rates. Cyclic phosphorylation is inhibited by Phospholipase D, presumably because Phospholipase D exerts an uncoupling effect.
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Affiliation(s)
- H Uhrig
- Botanisches Institut II der Universität Karlsruhe, Kaiserstraße 12, D-7500, Karlsruhe 1, Federal Republic of Germany
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Da Silva JV, Naylor AW, Kramer PJ. Some ultrastructural and enzymatic effects of water stress in cotton (gossypium hirsutum L.) leaves. Proc Natl Acad Sci U S A 1974; 71:3243-7. [PMID: 4528731 PMCID: PMC388660 DOI: 10.1073/pnas.71.8.3243] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Water stress induced by floating discs cut from cotton leaves (Gossypium hirsutum L. cultivar Stoneville) on a polyethylene glycol solution (water potential, -10 bars) was associated with marked alteration of ultrastructural organization of both chloroplasts and mitochondria. Ultrastructural organization of chloroplasts was sometimes almost completely destroyed; peroxisomes seemed not to be affected; and chloroplast ribosomes disappeared. Also accompanying water stress was a sharp increase in activity of acid phosphatase [orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2], and acid and alkaline lipase [glycerol ester hydrolase EC 3.1.1.3] within chloroplasts. Only acid lipase activity was detected inside mitochondria of stressed discs. These alterations in cell organization and enzymology may account for at least part of the previously reported effects of water stress on the CO(2) compensation point, photochemical reactions, and photorespiration.
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Some aspects of lamellar structure in various green leaf particles, indicated by oleic acid effects. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/0304-4211(74)90125-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Takaoki T, Torres-Pereira J, Packer L. Factors affecting the stability of chloroplast membranes in vitro. BIOCHIMICA ET BIOPHYSICA ACTA 1974; 352:260-7. [PMID: 4407357 DOI: 10.1016/0005-2736(74)90217-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Baszyński T. Effect of alpha-tocopherol on reconstitution of photosystem I in heptane-extracted spinach chloroplasts. BIOCHIMICA ET BIOPHYSICA ACTA 1974; 347:31-5. [PMID: 4154780 DOI: 10.1016/0005-2728(74)90197-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Siegenthaler PA. Inhibition of photosystem II electron transport in chloroplasts by fatty acids and restoration of its activity by Mn2+. FEBS Lett 1974; 39:337-40. [PMID: 4852481 DOI: 10.1016/0014-5793(74)80144-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Properties of chloroplasts and chloroplast fragments, as deduced from internal chlorophyll → chlorophyllide conversion. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/s0044-328x(74)80018-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Siegenthaler PA. Change in pH dependence and sequential inhibition of photosynthetic activity in chloroplasts by unsaturated fatty acids. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 305:153-62. [PMID: 4719597 DOI: 10.1016/0005-2728(73)90240-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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