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Liang A, Ma C, Xiao J, Hao Y, Li H, Guo Y, Cao Y, Jia W, Han L, Chen G, Tan Q, White JC, Xing B. Micro/nanoscale bone char alleviates cadmium toxicity and boosts rice growth via positively altering the rhizosphere and endophytic microbial community. JOURNAL OF HAZARDOUS MATERIALS 2023; 454:131491. [PMID: 37121038 DOI: 10.1016/j.jhazmat.2023.131491] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/10/2023] [Accepted: 04/23/2023] [Indexed: 05/19/2023]
Abstract
This present study investigated pork bone-derived biochar as a promising amendment to reduce Cd accumulation and alleviate Cd-induced oxidative stress in rice. Micro/nanoscale bone char (MNBC) pyrolyzed at 400 °C and 600 °C was synthesized and characterized before use. The application rates for MNBCs were set at 5 and 25 g·kg-1 and the Cd exposure concentration was 15 mg·kg-1. MNBCs increased rice biomass by 15.3-26.0% as compared to the Cd-alone treatment. Both types of MNBCs decreased the bioavailable Cd content by 27.4-54.8%; additionally, the acid-soluble Cd fraction decreased by 10.0-12.3% relative to the Cd alone treatment. MNBC significantly reduced the cell wall Cd content by 50.4-80.2% relative to the Cd-alone treatment. TEM images confirm the toxicity of Cd to rice cells and that MNBCs alleviated Cd-induced damage to the chloroplast ultrastructure. Importantly, the addition of MNBCs decreased the abundance of heavy metal tolerant bacteria, Acidobacteria and Chloroflexi, by 29.6-41.1% in the rhizosphere but had less impact on the endophytic microbial community. Overall, our findings demonstrate the significant potential of MNBC as both a soil amendment for heavy metal-contaminated soil remediation and for crop nutrition in sustainable agriculture.
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Affiliation(s)
- Anqi Liang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Chuanxin Ma
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, United States; The Connecticut Agricultural Experiment Station, New Haven, CT 06504, United States.
| | - Jiang Xiao
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, Zhejiang 311400, China
| | - Yi Hao
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, United States
| | - Hao Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Yaozu Guo
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Yini Cao
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, Hunan 410004, China
| | - Weili Jia
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, School of Environment, South China Normal University, Guangzhou 510006, China
| | - Lanfang Han
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Guangcai Chen
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, Zhejiang 311400, China
| | - Qian Tan
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jason C White
- The Connecticut Agricultural Experiment Station, New Haven, CT 06504, United States
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, United States
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Bayer RG, Stael S, Teige M. Chloroplast Isolation and Enrichment of Low-Abundance Proteins by Affinity Chromatography for Identification in Complex Proteomes. Methods Mol Biol 2021; 2261:535-547. [PMID: 33421013 DOI: 10.1007/978-1-0716-1186-9_34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Comprehensive knowledge of the proteome is a crucial prerequisite to understand dynamic changes in biological systems. Particularly low-abundance proteins are of high relevance in these processes as these are often proteins involved in signal transduction and acclimation responses. Although technological advances resulted in a tremendous increase in protein identification sensitivity by mass spectrometry (MS), the dynamic range in protein abundance is still the most limiting problem for the detection of low-abundance proteins in complex proteomes. These proteins will typically escape detection in shotgun MS experiments due to the presence of high-abundance proteins. Therefore, specific enrichment strategies are still required to overcome this technical limitation of MS-based protein discovery. We have searched for novel signal transduction proteins, more specifically kinases and calcium-binding proteins, and here we describe different approaches for enrichment of these low-abundance proteins from isolated chloroplasts from pea and Arabidopsis for subsequent proteomic analysis by MS. These approaches could be extended to include other signal transduction proteins and target different organelles.
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Affiliation(s)
- Roman G Bayer
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
| | - Simon Stael
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
- VIB Department of Plant Systems Biology, Ghent University, Ghent, Belgium
| | - Markus Teige
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria.
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria.
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Shen Y, Li J, Gu R, Zhan X, Xing B. Proteomic analysis for phenanthrene-elicited wheat chloroplast deformation. ENVIRONMENT INTERNATIONAL 2019; 123:273-281. [PMID: 30553200 DOI: 10.1016/j.envint.2018.11.074] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 11/22/2018] [Accepted: 11/29/2018] [Indexed: 06/09/2023]
Abstract
The exposure of polycyclic aromatic hydrocarbons (PAHs) can cause wheat leaf chlorosis. Thus, we hypothesize that chloroplast inner structure damage is the reason for leaf chlorosis. This study was conducted with the wheat seedlings exposed to Hoagland nutrient solution containing 1.0 mg L-1 phenanthrene for 9 days. Subcellular observation showed that chloroplast turns round and loses its structural integrity. Herein, iTRAQ (isobaric tag for relative and absolute quantification) was applied to analyze the changes of protein profile in chloroplast exposed to phenanthrene. A total of 517 proteins are identified, 261 of which are up-regulated. Eight proteins related with thylakoid (the structural component of chloroplast) are down-regulated and the expression of related genes further confirms the proteomic results through real-time PCR under phenanthrene treatment, suggesting that the thylakoid destruction is the reason for chloroplast deformation. Four proteins related with envelope and stroma are up-regulated, and this is the reason why chloroplast remains round. This study is useful in discussing the carcinogenic and teratogenic effects of PAHs in plant cells in the environment, and provides necessary knowledge for improving crop resistance to PAH pollution.
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Affiliation(s)
- Yu Shen
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, China; Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA
| | - Jinfeng Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, China
| | - Ruochen Gu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, China
| | - Xinhua Zhan
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, China.
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA
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Chloroplast isolation and affinity chromatography for enrichment of low-abundant proteins in complex proteomes. Methods Mol Biol 2015; 1295:211-23. [PMID: 25820724 DOI: 10.1007/978-1-4939-2550-6_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Detailed knowledge of the proteome is crucial to advance the biological sciences. Low-abundant proteins are of particular interest to many biologists as they include, for example those proteins involved in signal transduction. Recent technological advances resulted in a tremendous increase in protein identification sensitivity by mass spectrometry (MS). However, the dynamic range in protein abundance still forms a fundamental problem that limits the detection of low-abundant proteins in complex proteomes. These proteins will typically escape detection in shotgun MS experiments due to the presence of other proteins at an abundance several-fold higher in order of magnitude. Therefore, specific enrichment strategies are required to overcome this technical limitation of MS-based protein discovery. We have searched for novel signal transduction proteins, more specifically kinases and calcium-binding proteins, and here we describe different approaches for enrichment of these low-abundant proteins from isolated chloroplasts from pea and Arabidopsis for subsequent proteomic analysis by MS. These approaches could be extended to include other signal transduction proteins and target different organelles.
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5
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Bayer RG, Stael S, Csaszar E, Teige M. Mining the soluble chloroplast proteome by affinity chromatography. Proteomics 2011; 11:1287-99. [PMID: 21365755 PMCID: PMC3531887 DOI: 10.1002/pmic.201000495] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 12/15/2010] [Accepted: 12/29/2010] [Indexed: 12/28/2022]
Abstract
Chloroplasts are fundamental organelles enabling plant photoautotrophy. Besides their outstanding physiological role in fixation of atmospheric CO(2), they harbor many important metabolic processes such as biosynthesis of amino acids, vitamins or hormones. Technical advances in MS allowed the recent identification of most chloroplast proteins. However, for a deeper understanding of chloroplast function it is important to obtain a complete list of constituents, which is so far limited by the detection of low-abundant proteins. Therefore, we developed a two-step strategy for the enrichment of low-abundant soluble chloroplast proteins from Pisum sativum and their subsequent identification by MS. First, chloroplast protein extracts were depleted from the most abundant protein ribulose-1,5-bisphosphate carboxylase/oxygenase by SEC or heating. Further purification was carried out by affinity chromatography, using ligands specific for ATP- or metal-binding proteins. By these means, we were able to identify a total of 448 proteins including 43 putative novel chloroplast proteins. Additionally, the chloroplast localization of 13 selected proteins was confirmed using yellow fluorescent protein fusion analyses. The selected proteins included a phosphoglycerate mutase, a cysteine protease, a putative protein kinase and an EF-hand containing substrate carrier protein, which are expected to exhibit important metabolic or regulatory functions.
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Affiliation(s)
- Roman G Bayer
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Austria
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Tejwani GA. Regulation of fructose-bisphosphatase activity. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 54:121-94. [PMID: 6303063 DOI: 10.1002/9780470122990.ch3] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Cui L, Veeraraghavan N, Richter A, Wall K, Jansen RK, Leebens-Mack J, Makalowska I, dePamphilis CW. ChloroplastDB: the Chloroplast Genome Database. Nucleic Acids Res 2006; 34:D692-6. [PMID: 16381961 PMCID: PMC1347418 DOI: 10.1093/nar/gkj055] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Chloroplast Genome Database (ChloroplastDB) is an interactive, web-based database for fully sequenced plastid genomes, containing genomic, protein, DNA and RNA sequences, gene locations, RNA-editing sites, putative protein families and alignments (http://chloroplast.cbio.psu.edu/). With recent technical advances, the rate of generating new organelle genomes has increased dramatically. However, the established ontology for chloroplast genes and gene features has not been uniformly applied to all chloroplast genomes available in the sequence databases. For example, annotations for some published genome sequences have not evolved with gene naming conventions. ChloroplastDB provides unified annotations, gene name search, BLAST and download functions for chloroplast encoded genes and genomic sequences. A user can retrieve all orthologous sequences with one search regardless of gene names in GenBank. This feature alone greatly facilitates comparative research on sequence evolution including changes in gene content, codon usage, gene structure and post-transcriptional modifications such as RNA editing. Orthologous protein sets are classified by TribeMCL and each set is assigned a standard gene name. Over the next few years, as the number of sequenced chloroplast genomes increases rapidly, the tools available in ChloroplastDB will allow researchers to easily identify and compile target data for comparative analysis of chloroplast genes and genomes.
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Affiliation(s)
| | - Narayanan Veeraraghavan
- Center for Computational Genomics, Huck Institutes of Life Sciences, The Pennsylvania State UniversityUniversity Park, PA 16802, USA
| | - Alexander Richter
- Center for Computational Genomics, Huck Institutes of Life Sciences, The Pennsylvania State UniversityUniversity Park, PA 16802, USA
| | | | - Robert K. Jansen
- Section of Integrative Biology, The University of Texas at AustinAustin, TX 78712, USA
| | | | - Izabela Makalowska
- Center for Computational Genomics, Huck Institutes of Life Sciences, The Pennsylvania State UniversityUniversity Park, PA 16802, USA
| | - Claude W. dePamphilis
- To whom correspondence should be addressed. Tel: +1 814 863 6412; Fax: +1 814 865 9131;
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8
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Structure and Properties of Copper-Zinc Superoxide Dismutases. ADVANCES IN INORGANIC CHEMISTRY 1998. [DOI: 10.1016/s0898-8838(08)60026-4] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Nel W, Terblanche SE. Plant fructose-1,6-bisphosphatases: characteristics and properties. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1992; 24:1267-83. [PMID: 1322844 DOI: 10.1016/0020-711x(92)90201-b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In this minireview the properties and characteristics of plant fructose-1,6-bisphosphatases (D-fructose-1,6-bisphosphatase 1-phosphohydrolase, EC 3.1.3.11) are discussed. The properties and characteristics of the chloroplastic and cytoplasmic forms of the enzyme are reviewed. For purposes of comparison some reference is made to fructose-1,6-bisphosphatases from other species.
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Affiliation(s)
- W Nel
- Department of Biochemistry, University of Zululand, Private Bag, Republic of South Africa
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10
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Laudenbach DE, Trick CG, Straus NA. Cloning and characterization of an Anacystis nidulans R2 superoxide dismutase gene. MOLECULAR & GENERAL GENETICS : MGG 1989; 216:455-61. [PMID: 2501651 DOI: 10.1007/bf00334390] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The E. coli iron superoxide dismutase gene (sodB) was utilized as a heterologous probe to isolate a superoxide dismutase (sod) gene from Anacystis nidulans R2. Nucleotide sequence analysis revealed a 603 bp open reading frame with deduced amino acid sequence similar to other sod genes and to cyanobacterial superoxide dismutase amino-terminal sequences. Assuming proteolytic cleavage of the initial methionine residue, the molecular mass of the mature A. nidulans R2 sodB polypeptide is 22,000 daltons. Only a single copy of the superoxide dismutase sequence was detected in the A. nidulans R2 genome using Southern hybridization. Northern hybridization analysis indicated a single, monocistronic RNA transcript of approximately 720 bases. Primer extension mapping localized the transcription start site to 46 bases upstream from the initial methionine residue. A single orientation of a 2.1 kb PstI fragment containing the entire sod gene cloned into pUC18 was able to complement E. coli sodAsodB mutants. Complementation of the E. coli mutants was based on the ability of the cells to grow aerobically on minimal glucose medium. Growth curves of the complemented E. coli sodAsodB mutants showed that these cells exhibited levels of resistance to paraquat comparable to that of the wild-type E. coli phenotype.
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Affiliation(s)
- D E Laudenbach
- University of Toronto, Department of Botany, Ontario, Canada
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11
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Alteration in the metabolism of free radicals in wheat seedlings grown in the presence of 4-chloro-5-dimethylamino-2-phenyl-3(2H) pyridazinone. J Biosci 1986. [DOI: 10.1007/bf02716644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Redmond MJ, McEuen AR, Powls R. Superoxide dismutase in Scenedesmus obliquus : Effect of growth conditions and initial characterization. PLANTA 1985; 163:405-410. [PMID: 24249413 DOI: 10.1007/bf00395150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/1984] [Accepted: 08/14/1984] [Indexed: 06/02/2023]
Abstract
In heterotrophically grown Scenedesmus obliquus, the specific activity of superoxide dismutase (SOD; EC 1.15.1.1) declined when glucose was abundant, increased as it was depleated, and remained steady at a high level when it was absent. Transition to autotrophic growth produced only a small (20% over 5 d) increase in specific activity above the values obtained in dark-grown cells after glucose and starch-reserve depletion. This small, but consistent, increase did, however, parallel a similar increase in photosynthetic capacity. Polyacrylamide-gel electrophoresis showed the existence of nine isoenzymes of SOD. The three major and one of the minor isoenzymes were present in all extracts while three minor isoenzymes were found only in autotrophically grown cells and two only in heterotrophically grown cells. Characterization studies indicated that two of the major isoenzymes are dimeric FeSODs the other is a tetrameric MnSOD, and of the minor isoenzymes, two are dimeric FeSODs and four are dimeric MnSODs.
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Affiliation(s)
- M J Redmond
- Department of Biochemistry, University of Liverpool, P.O. Box 147, L69 3BX, Liverpool, UK
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Naftalin RJ. The thermostatics and thermodynamics of cotransport. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 778:155-75. [PMID: 6093878 DOI: 10.1016/0005-2736(84)90459-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The thermostatics of cotransport are reviewed. A static-head equilibrium state across a cotransport system, without leaks, is thought to occur when the electrochemical potential of the driven solute, B prevents net flow of the driving solute, A. For a symport this gives the relationship (formula: see text) Where n is the stoichiometric coefficient, namely the number of moles of A transported per mole of B. (2) If either a symporter with a 2:1 stoichiometric coefficient and a 1:1 symporter, or alternatively, a 1:1 symporter and a 1:1 antiporter are placed in a series membrane array, then the predicted static-head equilibrium across the entire array conflicts with the zeroth law of thermodynamics. (3) There are two major reasons for this failure of cotransport theory; these are: (A) the thermostatic relationships derived shown in Point 1 are based on the assumption that the cotransport process takes place within a closed system. However, the membrane and the external reservoirs are open to the cotransported ligands. It follows that A and B in the external reservoirs can vary independently of the changes within the cotransport process. As no chemical reaction between A and B occurs in the external solutions, reactions within the membrane phase do not affect the equilibrium between the transported ligands in the open reservoirs. (B) It is assumed that the law of mass action can be applied to the cotransport chemical reactions within the membrane phase, without any allowance for the fact that these reactions occur within a 'small thermodynamic system'. Any proper analysis of the chemical potential of the transported intermediate must consider the effects of lower order ligand-carrier forms, which coexist and compete for space with the higher order cotransported forms on the binding matrix. If account is taken of this necessity, then a simple extension of the work of Hill and Kedem (1966) J. Theor. Biol. 10, 399-441 shows that: (a) the static-head equilibrium state cannot exist; (b) the stoichiometry of cotransport, whether symport, or antiport, does not affect the static-head distribution of cotransported ligands; (c) the hypothetical net charge of the transported ligand-carrier complex does not affect static-head equilibrium; (d) the only equilibrium state where there is zero net flow of both driving and driven transported ligand is at true equilibrium when the ligands are uniformly distributed across the membrane. (4) It is deduced that cotransport is not entirely an affinity-driven, but is partially an entropy-driven process.(ABSTRACT TRUNCATED AT 400 WORDS)
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Tytler E, Wong T, Codd G. Photoinactivation in vivo of superoxide dismutase and catalase in the cyanobacteriumMicrocystis aeruginosa. FEMS Microbiol Lett 1984. [DOI: 10.1111/j.1574-6968.1984.tb01070.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Abstract
Molecular oxygen, itself not very reactive, can be converted by photosensitization to electronically excited singlet states, and by partial reduction to the superoxide and hydroxyl free radicals and to hydrogen peroxide. The very considerable toxicity of oxygen, which is due primarily to the properties of these derivatives, is ordinarily overlooked because aerobes have evolved an elaborate system of defenses which is reasonably adequate under ambient conditions. This toxicity becomes all too apparent when these defenses are overwhelmed at elevated pO2 or through the action of compounds which increase the conversion of oxygen to its more reactive derivatives. We will here consider the threat posed by oxygen and the defenses which make aerobic life possible.
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Ramaswamy N, Sangeeta G, Behere A, Nair P. Glyoxylate synthetase isolated from green potato tuber chloroplasts catalysing the conversion of formate to glyoxylate. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0304-4211(83)90117-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Hosein B, Palmer G. The kinetics and mechanism of oxidation of reduced spinach ferredoxin by molecular oxygen and its reduced products. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1983. [DOI: 10.1016/0005-2728(83)90045-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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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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Charles SA, Halliwell B. Light activation of fructose bisphosphatase in photosynthetically competent pea chloroplasts. Biochem J 1981; 200:357-63. [PMID: 6280684 PMCID: PMC1163543 DOI: 10.1042/bj2000357] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The fructose bisphosphatase (EC 3.1.3.11) activity of type A chloroplasts isolated from young (9-day-old) pea (Pisum sativum var. Progress no. 9) plants, assayed at physiological pH, substrate and Mg2+ concentrations, increased rapidly on illumination. The enzyme activity detected was more than sufficient to account for observed rates of Co2 fixation both during the induction period and during steady-state CO2 fixation, whether or not dihydroxyacetone phosphate had been added to the preparation. Omission of catalase from the suspension medium had no effect. On switching off the light, CO2 fixation by the chloroplasts ceased at once, yet fructose bisphosphatase activity decreased much more slowly. Changes in enzyme activity were much less marked if assays were conducted at 3 mM substrate and 10 mM-Mg2+. Chloroplasts from older (13--20-day-old) peas only fixed CO2 rapidly if catalase was present in the assay medium. The fructose bisphosphatase activity detected under physiological assay conditions was again more than sufficient to account for observed rates of Co2 fixation. In the presence of added dihydroxyacetone phosphate, however, the rate of Co2 fixation appeared to be determined by the rate of light activation of fructose bisphosphatase. In general, the rates of Co2 fixation and enzyme activation, and the final enzyme activity achieved, decreased markedly with increasing age of the plants. The role of light activation of fructose bisphosphatase as a means of controlling the rate of CO2 fixation in pea chloroplasts is discussed.
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Charles SA, Halliwell B. The role of calcium ions and the thioredoxin system in regulation of spinach chloroplast fructosebisphosphatase. Cell Calcium 1981. [DOI: 10.1016/0143-4160(81)90037-3] [Citation(s) in RCA: 12] [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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22
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Charles SA, Halliwell B. Light activation of fructose bisphosphatase in isolated spinach chloroplasts and deactivation by hydrogen peroxide : A physiological role for the thioredoxin system. PLANTA 1981; 151:242-246. [PMID: 24301849 DOI: 10.1007/bf00395175] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/1980] [Accepted: 10/15/1980] [Indexed: 06/02/2023]
Abstract
Spinach chloroplast fructose bisphosphatase (EC 3.1.3.11.) exists in both oxidised and reduced forms. Only the latter has the kinetic properties that allow it to function at physiological concentrations of fructose 1,6-bisphosphate and Mg(2+). Illumination of freshly prepared type A chloroplasts causes a conversion of oxidised to reduced enzyme. The rate of this conversion does not limit the rate of CO2 fixation. In the dark the reduced enzyme partially reverts back to the oxidised form. If catalase is omitted from the reaction medium the rate of CO2 fixation by chloroplasts is decreased and seems to be limited by the rate of conversion of the enzyme to the reduced form. The physiological significance of the light dependent generation of dithiol compounds (such as thioredoxin) within chloroplasts is discussed.
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Affiliation(s)
- S A Charles
- Department of Biochemistry, University of London, King's College, Strand, WC2R 2LS, London, UK
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Droppa M, Horváth G, Mustárdy LA, Demeter S, Faludi-Dániel A. Structural and functional stability of isolated intact chloroplasts. PHOTOSYNTHESIS RESEARCH 1981; 2:31-38. [PMID: 24470154 DOI: 10.1007/bf00036163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/1980] [Revised: 02/11/1981] [Indexed: 06/03/2023]
Abstract
The effect of in vitro ageing on the ultrastructure, electron transport, thermoluminescence and flash-induced 515 nm absorbance change of isolated intact (type A) chloroplasts compared with non-intact (types B and C) chloroplasts was studied.When stored in the dark for 18 h at 5°C, the structural characteristics of intact and non-intact chloroplasts were only slightly altered. The most conspicuous difference between the two was in the coupling of the electron transport which was tighter and more stable in intact chloroplasts. Under dark-storage the activity of PS 2* decreased and the -20°C peak of thermoluminescence increased at the expense of the emission at +25°C. These changes were less pronounced in the intact chloroplasts. PS 1 activity and the flash-induced 515 nm absorbance change were not affected by dark-storage.When kept in the light (80 W m(-2) (400-700 nm) for 1 h at 5°C), the thylakoid system of chloroplasts rapidly became disorganized. Although the initial activity of electron transport was much higher in intact chloroplasts, after a short period of light-storage the linear electron transport and the electron transport around PS 2 decreased in both types of preparations to the same low level. These changes were accompanied by an overall decrease of the intensity of thermoluminescence. PS 1 was not inhibited by light-storage, while the flash-induced 515 nm absorbance change was virtually abolished both in preparations of intact and non-intact chloroplasts.The data show that in stored chloroplast preparations intactness cannot be estimated reliably either by the FeCy test or by inspection under the electron microscope. These tests should be cross-checked on the level and coupling of the electron transport.
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Affiliation(s)
- M Droppa
- Institute of Plant Physiology, Biological Research Center, Hungarian Academy of Sciences, P.O.B. 521, H-6701, Szeged, Hungary
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Graves MC, Breitenberger CA, Spremulli LL. Euglena gracilis chloroplast ribosomes: improved isolation procedure and comparison of elongation factor specificity with prokaryotic and eukaryotic ribosomes. Arch Biochem Biophys 1980; 204:444-54. [PMID: 6778393 DOI: 10.1016/0003-9861(80)90055-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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26
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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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Charles SA, Halliwell B. Effect of hydrogen peroxide on spinach (Spinacia oleracea) chloroplast fructose bisphosphatase. Biochem J 1980; 189:373-6. [PMID: 6257234 PMCID: PMC1162009 DOI: 10.1042/bj1890373] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Thiol-treated spinach (Spinacia oleracea) chloroplast fructose bisphosphatase (EC 3.1.3.11) is severely inhibited by H2O2, whereas the freshly purified enzyme is little affected. Dithiothreitol reverses inhibition by H2O2, indicating that essential thiol groups are oxidized during H2O2 inactivation. A new role for the dithiol and thioredoxin systems that are operative in illuminated chloroplasts is proposed.
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28
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Moore AL, Dench JE, Jackson C, Hall DO. Glycine decarboxylase activity in plant tissues measured by a rapid assay technique. FEBS Lett 1980; 115:54-8. [PMID: 7389918 DOI: 10.1016/0014-5793(80)80725-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Charles SA, Halliwell B. Properties of freshly purified and thiol-treated spinach chloroplast fructose bisphosphatase. Biochem J 1980; 185:689-93. [PMID: 6248029 PMCID: PMC1161446 DOI: 10.1042/bj1850689] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Freshly purified spinach chloroplast fructose bisphosphatase is powerfully inhibited by inorganic phosphate competitively with respect to its substrate fructose 1,6-bisphosphate. The concentrations of phosphate and substrate in the chloroplast stroma are such that the enzyme in this form could not operate at a significant rate in vivo. Incubation of the enzyme with dithiothreitol for 24 h decreases the Km for fructose 1,6-bisphosphate from 0.8 to 0.033 mM, decreases the Km for Mg2+ from 9 to 2 mM and substantially alleviates inhibition by inorganic phosphate. The physiological significance of thiol activation of the enzyme is discussed.
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31
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Mills WR, Joy KW. A rapid method for isolation of purified, physiologically active chloroplasts, used to study the intracellular distribution of amino acids in pea leaves. PLANTA 1980; 148:75-83. [PMID: 24311269 DOI: 10.1007/bf00385445] [Citation(s) in RCA: 82] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1979] [Accepted: 11/13/1979] [Indexed: 05/12/2023]
Abstract
A procedure is described for the rapid (<5 min) isolation of purified, physiologically active chloroplasts from Pisum sativum L. Mitochondrial and microbody contamination is substantially reduced and broken chloroplasts are excluded by washing through a layer containing a treated silica sol. On average the preparations contain 93% intact chloroplasts and show high rates of (14)CO2 fixation and CO2-dependent O2 evolution (over 100 μmol/mg chlorophyll(chl)/h); they are also able to carry out light-driven incorporation of leucine into protein (4 nmol/mg chl/h). The amino-acid contents of chloroplasts prepared from leaves and from leaf protoplasts have been determined. Asparagine is the most abundant amino acid in the pea chloroplast (>240 nmol/mg chl), even thought it is proportionately lower in the chloroplast relative to the rest of the cell. The chloroplasts contain about 20% of many of the amino acids of the cell, but for individual amino acids the percentage in the chloroplast ranges from 8 to 40% of the cell total. Glutamic acid, glutamine and aspartic acid are enriched in the chloroplasts, while asparagine, homoserine and β-(isoxazolin-5-one-2-yl)-alanine are relatively lower. Leakage of amino acids from the chloroplast during preparation or repeated washing was ca. 20%. Some differences exist between the amino-acid composition of chloroplasts isolated from intact leaves and from protoplasts. In particular, γ-aminobutyric acid accumulates to high levels, while homoserine and glutamic acid decrease, during protoplast formation and breakage.
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Affiliation(s)
- W R Mills
- Department of Biology and Institute of Biochemistry, Carleton University, K1S 5B6, Ottawa, Ont., Canada
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Shigeoka S, Nakano Y, Kitaoka S. Metabolism of hydrogen peroxide in Euglena gracilis Z by L-ascorbic acid peroxidase. Biochem J 1980; 186:377-80. [PMID: 6768357 PMCID: PMC1161541 DOI: 10.1042/bj1860377] [Citation(s) in RCA: 115] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Euglena gracilis was found to contain a peroxidase that specifically require L-ascorbic acid as the natural electron donor in the cytosol. The presence of an oxidation-reduction system metabolizing L-ascorbic acid was demonstrated in Euglena cells. Oxidation of L-ascorbic acid by the peroxidase, and the absence of ascorbic acid oxidase activity, suggests that the system functions to remove H2O2 in E. gracilis, which lacks catalase.
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Codd GA, Stewart R. The Photoinactivation of Micro-Algal Ribulose Bisphosphate Carboxylase; its Physiological and Ecological Significance. THE BLUE LIGHT SYNDROME 1980. [DOI: 10.1007/978-3-642-67648-2_35] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Groden D, Beck E. H2O2 destruction by ascorbate-dependent systems from chloroplasts. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 546:426-35. [PMID: 454577 DOI: 10.1016/0005-2728(79)90078-1] [Citation(s) in RCA: 144] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Washed lamellae from isolated spinach chloroplasts exhibited peroxidative activity with 3,3'-diaminobenzidine or ascorbate as electron donors. By heat treatment or by incubation of the chloroplasts with pronase a heat-labile enzymic activity (system A) and a heat-stable non-enzymic peroxidative activity (system B) could be differentiated. System A is membrane-bound, reacts with 3,3'-diaminobenzidine and with ascorbate as electron donors, shows a sharp pH optimum between 7.5 and 8.0 with both substrates and is inhibited competitively by cyanide. The heat-stable factor can be extracted from the chloroplast lamellae by heat treatment, reacts only with ascorbate as electron donor, shows increasing activity with higher pH values but no optimum and is not inhibited by cyanide. Both peroxidative systems in connection with a relatively high concentration of ascorbate in chloroplasts should represent an important tool for the detoxification of H2O2 which is produced in these organelles by photosynthetic O2 reduction.
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Quinn PJ, Williams WP. Plant lipids and their role in membrane function. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1979; 34:109-73. [PMID: 375299 DOI: 10.1016/0079-6107(79)90016-6] [Citation(s) in RCA: 133] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Jackson C, Dench J, Moore AL, Halliwell B, Foyer CH, Hall DO. Subcellular localisation and identification of superoxide dismutase in the leaves of higher plants. EUROPEAN JOURNAL OF BIOCHEMISTRY 1978; 91:339-44. [PMID: 729573 DOI: 10.1111/j.1432-1033.1978.tb12685.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
1. The subcellular location of superoxide dismutase in the leaves of spinach and other C3 plants has been investigated. 2. Most activity appeared to be located within chloroplasts. These organelles contain a cyanide-sensitive (copper-zinc) superoxide dismutase, most of which is located in the stroma although some is bound to the thylakoids. 3. Intact chloroplast fractions also contain a cyanide-insensitive (manganese) superoxide dismutase, but this activity is located on the outside of the chloroplasts and may be adsorbed onto them during isolation. 4. Leaf mitochondrial fractions contain only a small percentage of total leaf superoxide dismutase activity, but there is more than can be accounted for by contamination with chloroplasts. 5. Mitochondria contain both a cyanide-sensitive dismutase, apparently located in the intermembrane space, and a cyanide-insensitive activity, apparently located in the matrix. 6. The microsomal fraction contains no superoxide dismutase activity.
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Halliwell B, Foyer CH. Properties and physiological function of a glutathione reductase purified from spinach leaves by affinity chromatography. PLANTA 1978; 139:9-17. [PMID: 24414099 DOI: 10.1007/bf00390803] [Citation(s) in RCA: 181] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/1977] [Accepted: 11/14/1977] [Indexed: 05/05/2023]
Abstract
Glutathione reductase (EC 1.6.4.2) was purified from spinach (Spinacia oleracea L.) leaves by affinity chromatography on ADP-Sepharose. The purified enzyme has a specific activity of 246 enzyme units/mg protein and is homogeneous by the criterion of polyacrylamide gel electrophoresis on native and SDS-gels. The enzyme has a molecular weight of 145,000 and consists of two subunits of similar size. The pH optimum of spinach glutathione reductase is 8.5-9.0, which is related to the function it performs in the chloroplast stroma. It is specific for oxidised glutathione (GSSG) but shows a low activity with NADH as electron donor. The pH optimum for NADH-dependent GSSG reduction is lower than that for NADPH-dependent reduction. The enzyme has a low affinity for reduced glutathione (GSH) and for NADP(+), but GSH-dependent NADP(+) reduction is stimulated by addition of dithiothreitol. Spinach glutathione reductase is inhibited on incubation with reagents that react with thiol groups, or with heavymetal ions such as Zn(2+). GSSG protects the enzyme against inhibition but NADPH does not. Pre-incubation of the enzyme with NADPH decreases its activity, so kinetic studies were performed in which the reaction was initiated by adding NADPH or enzyme. The Km for GSSG was approximately 200 μM and that for NADPH was about 3 μM. NADP(+) inhibited the enzyme, assayed in the direction of GSSG reduction, competitively with respect to NADPH and non-competitively with respect to GSSG. In contrast, GSH inhibited non-competitively with respect to both NADPH and GSSG. Illuminated chloroplasts, or chloroplasts kept in the dark, contain equal activities of glutathione reductase. The kinetic properties of the enzyme (listed above) suggest that GSH/GSSG ratios in chloroplasts will be very high under both light and dark conditions. This prediction was confirmed experimentally. GSH or GSSG play no part in the light-induced activation of chloroplast fructose diphosphatase or NADP(+)-glyceraldehyde-3-phosphate dehydrogenase. We suggest that GSH helps to stabilise chloroplast enzymes and may also play a role in removing H2O2. Glucose-6-phosphate dehydrogenase activity may be required in chloroplasts in the dark in order to provide NADPH for glutathione reductase.
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Affiliation(s)
- B Halliwell
- Department of Biochemistry, University of London King's College, Strand, WC2R 2LS, London, UK
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Krause GH, Kirk M, Heber U, Osmond CB. O2-dependent inhibition of photosynthetic capacity in intact isolated chloroplasts and isolated cells from spinach leaves illuminated in the absence of CO2. PLANTA 1978; 142:229-233. [PMID: 24408108 DOI: 10.1007/bf00388218] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/1978] [Accepted: 05/19/1978] [Indexed: 06/03/2023]
Abstract
When isolated intact chloroplasts or cells from spinach (Spinacia oleracea L.) leaves are incubated in the light in the absence of CO2, their capacity for subsequent CO2-dependent photosynthetic oxygen evolution is drastically decreased. This inhibition is light and oxygen-dependent and can be prevented by addition of bicarbonate. It is concluded that the normal dissipation of photosynthetic energy by carbon assimilation and in processes related to photorespiration is an essential condition for the physiological stability of illuminated intact chloroplasts and cells.
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Affiliation(s)
- G H Krause
- Botanisches Institut der Universität Düsseldorf, Universitätsstraße 1, D-4000, Düsseldorf, Federal Republic of Germany
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