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Sørensen M, Møller BL. Metabolic Engineering of Photosynthetic Cells – in Collaboration with Nature. Metab Eng 2021. [DOI: 10.1002/9783527823468.ch21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Afify AEMMR, El Baroty GS, El Baz FK, Abd El Baky HH, Murad SA. Scenedesmus obliquus: Antioxidant and antiviral activity of proteins hydrolyzed by three enzymes. J Genet Eng Biotechnol 2018; 16:399-408. [PMID: 30733753 PMCID: PMC6353658 DOI: 10.1016/j.jgeb.2018.01.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 11/22/2017] [Accepted: 01/16/2018] [Indexed: 12/26/2022]
Abstract
Purpose To obtain protein hydrolysates from fresh water green algae Scenedesmus obliquus by three different enzymes and evaluate its antioxidant and antiviral activity. Methods Enzymatic hydrolysates of green algae Scenedesmus obliquus protein were prepared by treatment with: 1.2% solution of pepsin, trypsin or papain. Protein was extracted from S. obliquus by three different extraction methods. Protein extracts and hydrolysates were assessed from stained gels following SDS–PAGE of samples. Antioxidant activity of protein hydrolysates was investigated. Results S. obliquus cells and protein extracts were rich in Arg, Lys, Asp, Ala, and His. Protein hydrolyzed by papain (Sd1pa) and protein hydrolyzed by trypsin (Sd2Try) induced highest antioxidant activity based on 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging (41.41% and 40.62%) respectively, and on 2,2′-azinobis 3-ethyl-benzothiazoline-6-sulphonate (ABTS) radical (87.03% and 45.12%) respectively, at 150 µg/ml. The inhibitory effect and mode of action of protein hydrolysates were evaluated against Coxsackie B3 virus (CVB3). Protein hydrolyzed by papain (Sd2pa) and protein hydrolyzed by pepsin (Sd1pep) at 100 µg/ml exhibited antiviral activity (66.2% and 57.6%, respectively), against (CVB3) from all protein hydrolysates. Conclusion S. obliquus protein hydrolysates have a potential as antioxidative neutraceutical ingredients and a potential therapeutic agent against CVB3.
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Affiliation(s)
| | - Gamal S El Baroty
- Biochemistry Department, Faculty of Agriculture, Cairo University, Cairo, Egypt
| | - Farouk K El Baz
- Plant Biochemistry Department, National Research Centre, Dokki, Cairo, Egypt
| | - Hanaa H Abd El Baky
- Plant Biochemistry Department, National Research Centre, Dokki, Cairo, Egypt
| | - Soha A Murad
- Plant Biochemistry Department, National Research Centre, Dokki, Cairo, Egypt
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Samek D, Mišurcová L, Machů L, Buňková L, Minařík A, Fišera M. Whole-Cell Protein Profiles of Disintegrated Freshwater Green Algae and Cyanobacterium. JOURNAL OF AQUATIC FOOD PRODUCT TECHNOLOGY 2014. [DOI: 10.1080/10498850.2013.819542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
Plants are light-driven "green" factories able to synthesize more than 200,000 different bioactive natural products, many of which are high-value products used as drugs (e.g., artemisinin, taxol, and thapsigargin). In the formation of natural products, cytochrome P450 (P450) monooxygenases play a key role in catalyzing regio- and stereospecific hydroxylations that are often difficult to achieve using the approaches of chemical synthesis. P450-catalyzed monooxygenations are dependent on electron donation typically from NADPH catalyzed by NADPH-cytochrome P450 oxidoreductase (CPR). The consumption of the costly cofactor NADPH constitutes an economical obstacle for biotechnological in vitro applications of P450s. This bottleneck has been overcome by the design of an in vitro system able to carry out light-driven P450 hydroxylations using photosystem I (PSI) for light harvesting and generation of reducing equivalents necessary to drive the P450 catalytic cycle. The in vitro system is based on the use of isolated PSI and P450 membrane complexes using ferredoxin as an electron carrier. The turnover rate of the P450 in the light-driven system was 413 min(-1) compared to 228 min(-1) in the native CPR-catalyzed system. The use of light as a substitute for costly NADPH offers a new avenue for P450-mediated synthesis of complex bioactive natural products using in vitro synthetic biology approaches.
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Affiliation(s)
- Kenneth Jensen
- Department
of Plant Biology and Biotechnology, ‡VKR Research Centre “Pro-Active Plants”, and §Center for Synthetic
Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Poul Erik Jensen
- Department
of Plant Biology and Biotechnology, ‡VKR Research Centre “Pro-Active Plants”, and §Center for Synthetic
Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Birger Lindberg Møller
- Department
of Plant Biology and Biotechnology, ‡VKR Research Centre “Pro-Active Plants”, and §Center for Synthetic
Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
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Golbeck JH. The binding of cofactors to photosystem I analyzed by spectroscopic and mutagenic methods. ANNUAL REVIEW OF BIOPHYSICS AND BIOMOLECULAR STRUCTURE 2003; 32:237-56. [PMID: 12524325 DOI: 10.1146/annurev.biophys.32.110601.142356] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review focuses on cofactor-ligand and protein-protein interactions within the photosystem I reaction center. The topics include a description of the electron transfer cofactors, the mode of binding of the cofactors to protein-bound ligands, and a description of intraprotein contacts that ultimately allow photosystem I to be assembled (in cyanobacteria) from 96 chlorophylls, 22 carotenoids, 2 phylloquinones, 3 [4Fe-4S] clusters, and 12 polypeptides. During the 15 years that have elapsed from the first report of crystals to the atomic-resolution X-ray crystal structure, cofactor-ligand interactions and protein-protein interactions were systematically being explored by spectroscopic and genetic methods. This article charts the interplay between these disciplines and assesses how good the early insights were in light of the current structure of photosystem I.
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Affiliation(s)
- John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
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Vassiliev IR, Antonkine ML, Golbeck JH. Iron-sulfur clusters in type I reaction centers. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1507:139-60. [PMID: 11687212 DOI: 10.1016/s0005-2728(01)00197-9] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Type I reaction centers (RCs) are multisubunit chlorophyll-protein complexes that function in photosynthetic organisms to convert photons to Gibbs free energy. The unique feature of Type I RCs is the presence of iron-sulfur clusters as electron transfer cofactors. Photosystem I (PS I) of oxygenic phototrophs is the best-studied Type I RC. It is comprised of an interpolypeptide [4Fe-4S] cluster, F(X), that bridges the PsaA and PsaB subunits, and two terminal [4Fe-4S] clusters, F(A) and F(B), that are bound to the PsaC subunit. In this review, we provide an update on the structure and function of the bound iron-sulfur clusters in Type I RCs. The first new development in this area is the identification of F(A) as the cluster proximal to F(X) and the resolution of the electron transfer sequence as F(X)-->F(A)-->F(B)-->soluble ferredoxin. The second new development is the determination of the three-dimensional NMR solution structure of unbound PsaC and localization of the equal- and mixed-valence pairs in F(A)(-) and F(B)(-). We provide a survey of the EPR properties and spectra of the iron-sulfur clusters in Type I RCs of cyanobacteria, green sulfur bacteria, and heliobacteria, and we summarize new information about the kinetics of back-reactions involving the iron-sulfur clusters.
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Affiliation(s)
- I R Vassiliev
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, 310 South Frear Building, University Park, PA 16802, USA
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8
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Golbeck JH, Mehari T, Parrett K, Ikegami I. Reconstitution of the photosystem I complex from the P700 and Fx-containing reaction center core protein and the FA/FBpolypeptide. FEBS Lett 2001. [DOI: 10.1016/0014-5793(88)80331-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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9
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Wynn R, Malkin R. Characterization of an isolated chloroplast membrane Fe◀S protein and its identification as the photosystem I Fe◀SA/Fe◀SBbinding protein. FEBS Lett 2001. [DOI: 10.1016/0014-5793(88)81143-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Oh-oka H, Takahashi Y, Matsubara H, Itoh S. EPR studies of a 9 kDa polypeptide with an iron-sulfur cluster(s) isolated from photosystem I complex byn-butanol extraction. FEBS Lett 2001. [DOI: 10.1016/0014-5793(88)80101-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Vassiliev IR, Yu J, Jung YS, Schulz R, Ganago AO, McIntosh L, Golbeck JH. The cysteine-proximal aspartates in the Fx-binding niche of photosystem I. Effect of alanine and lysine replacements on photoautotrophic growth, electron transfer rates, single-turnover flash efficiency, and EPR spectral properties. J Biol Chem 1999; 274:9993-10001. [PMID: 10187775 DOI: 10.1074/jbc.274.15.9993] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The FX electron acceptor in Photosystem I (PS I) is a highly electronegative (Em = -705 mV) interpolypeptide [4Fe-4S] cluster ligated by cysteines 556 and 565 on PsaB and cysteines 574 and 583 on PsaA in Synechocystis sp. PCC 6803. An aspartic acid is adjacent to each of these cysteines on PsaB and adjacent to the proline-proximal cysteine on PsaA. We investigated the effect of D566PsaB and D557PsaB on electron transfer through FX by changing each aspartate to the neutral alanine or to the positively charged lysine either singly (D566APsaB, D557APsaB, D566KPsaB, and D557KPsaB) or in pairs (D557APsaB/D566APsaB and D557KPsaB/D566APsaB). All mutants except for D557KPsaB/D566APsaB grew photoautotrophically, but the growth of D557KPsaB and D557APsaB/D566APsaB was impaired under low light. The doubling time was increased, and the chlorophyll content per cell was lower in D557KPsaB and D557APsaB/D566APsaB relative to the wild type and the other mutants. Nevertheless, the rates of NADP+ photoreduction in PS I complexes from all mutants were no less than 75% of that of the wild type. The kinetics of back-reaction of the electron acceptors on a single-turnover flash showed efficient electron transfer to the terminal acceptors FA and FB in PS I complexes from all mutants. The EPR spectrum of FX was identical to that in the wild type in all but the single and double D566APsaB mutants, where the high-field resonance was shifted downfield. We conclude that the impaired growth of some of the mutants is related to a reduced accumulation of PS I rather than to photosynthetic efficiency. The chemical nature and the charge of the amino acids adjacent to the cysteine ligands on PsaB do not appear to be significant factors in the efficiency of electron transfer through FX.
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Affiliation(s)
- I R Vassiliev
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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12
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Naver H, Scott MP, Golbeck JH, Olsen CE, Scheller HV. The eight-amino acid internal loop of PSI-C mediates association of low molecular mass iron-sulfur proteins with the P700-FX core in photosystem I. J Biol Chem 1998; 273:18778-83. [PMID: 9668051 DOI: 10.1074/jbc.273.30.18778] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The PSI-C subunit of photosystem I (PS I) shows similarity to soluble 2[4Fe-4S] ferredoxins. PSI-C contains an eight residue internal loop and a 15 residue C-terminal extension which are absent in the ferredoxins. The eight-residue loop has been shown to interact with PSI-A/PSI-B (Naver, H., Scott, M. P., Golbeck, J. H., Moller, B. L., and Scheller, H. V. (1996) J. Biol. Chem. 271, 8996-9001). Four mutant proteins were constructed. Two were modified barley PSI-C proteins, one lacking the loop and the C terminus (PSI-Ccore) and one where the loop replace the C-terminal extension (PSI-CcoreLc-term). Two were modified Clostridium pasteurianum ferredoxins, one with the loop of barley PSI-C and one with both the loop and the C terminus of PSI-C. Wild-type proteins and the mutants were used to reconstitute barley P700-FX cores lacking PSI-C, -D, and-E. Western blotting showed that PSI-CcoreLc-term binds to PS I, whereas PSI-Ccore does not. Without PSI-D the PSI-CcoreLc-term mutant accepts electrons from FX in contrast to PSI-C mutants without the loop. Flash photolysis of P700-FX cores reconstituted with C. pasteurianum ferredoxin showed that only the ferredoxin mutants with the loop accepted electrons from FX. From this, it is concluded that the loop of PSI-C is necessary and sufficient for the association between PS I and PSI-C, and that the loop is functional as an interaction domain even when positioned at the C terminus of PSI-C or on a low molecular mass, soluble ferredoxin.
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Affiliation(s)
- H Naver
- Plant Biochemistry Laboratory, Department of Plant Biology, The Royal Veterinary and Agricultural University, 40 Thorvaldsensvej, DK 1871 Frederiksberg C, Copenhagen, Denmark
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Naver H, Scott MP, Golbeck JH, Møller BL, Scheller HV. Reconstitution of barley photosystem I with modified PSI-C allows identification of domains interacting with PSI-D and PSI-A/B. J Biol Chem 1996; 271:8996-9001. [PMID: 8621546 DOI: 10.1074/jbc.271.15.8996] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The PSI-C subunit of photosystem I shows similarity to soluble 2[4Fe-4S] ferredoxins. Alignment analysis clearly shows that PSI-C contains an 8-residue internal loop and a 15-residue C-terminal extension that are absent in the ferredoxins. The remaining residues in PSI-C are likely to be folded in a way similar to the soluble 2[4Fe-4S] ferredoxins. Two modified PSI-C subunits lacking either the 8-residue loop or 10 residues of the C terminus were expressed in Escherichia coli and used to reconstitute a barley P700-FX core prepared to specifically lack PSI-C, PSI-D, and PSI-E. As shown by EPR spectroscopy, the modified proteins carry two [4Fe-4S] clusters with characteristics similar to those of native PSI-C. Western blot analysis of the reconstituted photosystem I complexes showed that the modified PSI-C proteins bind to the P700-FX core. Flash photolysis revealed that in photosystem I complexes reconstituted in the presence of PSI-D with the C-terminally deleted PSI-C, the FA/FB back-reaction was less efficiently restored than with wild-type PSI-C. The loop-deleted PSI-C was even less efficient. We attribute these differences to altered binding properties of the modified proteins. Comparison of reconstitutions performed in the presence and absence of PSI-D shows that the loop-deleted PSI-C is unable to bind without PSI-D, whereas the C-terminally deleted PSI-C binds only weakly with PSI-D. These results imply that the internal loop of PSI-C interacts with the PSI-A/B heterodimer and that the C terminus of PSI-C interacts with PSI-D.
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Affiliation(s)
- H Naver
- Department of Plant Biology, Royal Veterinary and Agricultural University, 40 Thorvaldsensvej, DK 1871 Frederiksberg C, Copenhagen, Denmark
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Matsubara H, Oh-Oka H, Takahashi Y, Fujita Y. Three iron-sulfur proteins encoded by three ORFs in chloroplasts and cyanobacteria. PHOTOSYNTHESIS RESEARCH 1995; 46:107-115. [PMID: 24301573 DOI: 10.1007/bf00020421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/1995] [Accepted: 05/02/1995] [Indexed: 06/02/2023]
Abstract
A brief review is presented on the gene products of frxA, frxB and frxC found in chloroplasts. The product of frxA shows high sequence homologies to bacterial 2[4Fe-4S] ferredoxins, but it functions as iron-sulfur centers A and B in Photosystem I, transferring electrons to [2Fe-2S] ferredoxin. This protein is located on surface of the thylakoid membranes in a state being covered by two other proteins. Proteins homologous to frxB product are found in mitochondrial respiratory Complex I and the product of frxB may function in chlororespiration, but at present no clear function of this protein is known. The frxC gene product is found to function in light-independent chlorophyll synthesis as one of the subunits of protochlorophyllide reductase and is reviewed in comparison to nitrogenase. Several problems and future research direction in these areas are also presented.
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Affiliation(s)
- H Matsubara
- Department of Biochemistry, Faculty of Science, Okayama University of Science, 700, Okayama, Japan
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Hallahan BJ, Purton S, Ivison A, Wright D, Evans MC. Analysis of the proposed Fe-SX binding region of Photosystem 1 by site directed mutation of PsaA in Chlamydomonas reinhardtii. PHOTOSYNTHESIS RESEARCH 1995; 46:257-264. [PMID: 24301590 DOI: 10.1007/bf00020438] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/1995] [Accepted: 07/11/1995] [Indexed: 06/02/2023]
Abstract
The psaA and psaB genes of the chloroplast genome in oxygenic photosynthetic organisms code for the major peptides of the Photosystem 1 reaction center. A heterodimer of the two polypeptides PsaA and PsaB is thought to bind the reaction center chlorophyll, P700, and the early electron acceptors A0, A1 and Fe-SX. Fe-SX is a 4Fe4S center requiring 4 cysteine residues as ligands from the protein. As PsaA and PsaB have only three and two conserved cysteine residues respectively, it has been proposed by several groups that Fe-SX is an unusual inter-peptide center liganded by two cysteines from each peptide. This hypothesis has been tested by site directed mutagenesis of PsaA residue C575 and the adjacent D576. The C575D mutant does not assemble Photosystem 1. The C575H mutant contains a photoxidisable chlorophyll with EPR properties of P700, but no other Photosystem 1 function has been detected. The D576L mutant assembles a modified Photosystem 1 in which the EPR properties of the Fe-SA/B centers are altered. The results confirm the importance of the conserved cysteine motif region in Photosystem 1 structure.
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Affiliation(s)
- B J Hallahan
- Department of Biology, University College London, Gower St, WC1E 6BT, London, UK
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Searle GF, Schaafsma TJ. Fluorescence detected magnetic resonance of the primary donor and inner core antenna chlorophyll in Photosystem I reaction centre protein: Sign inversion and energy transfer. PHOTOSYNTHESIS RESEARCH 1992; 32:193-206. [PMID: 24408360 DOI: 10.1007/bf00034795] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/1992] [Accepted: 03/24/1992] [Indexed: 05/28/2023]
Abstract
The Photosystem I reaction centre protein CP1, isolated from barley using polyacrylamide gel electrophoresis showed an EPR (Electron Paramgnetic Resonance) spectrum with the polarisation pattern AEEAAE, typical of the primary donor triplet state (3)P700, created via radical pair formation and recombination. (3)P700 could also be detected by Fluorescence Detected Magnetic Resonance (FDMR) at λf > 700 nm even in the presence of a large number of chlorophyll antennae. Its zero field splitting parameters, D=282.5×10(-4) cm(-1) and E=38.5×10(-4) cm(-1), were independent of the detection wavelength, and agreed with ADMR (Absorption Detected Magnetic Resonance) and EPR values. The signs of the (3)P700 D+E and D-E transitions were positive (increase in fluorescence intensity on applying a resonance microwave field). In contrast, in the emission band 685 < λf < 700 nm FDMR spectra with negative D+E and D-E transitions were detected, and the D value was wavelength-dependent. These FDMR results support an excitation energy transfer model for CP1, derived from time-resolved fluorescence studies, in which two chlorophyll antenna forms are distinguished, with fluorescence at 685 < λf < 700 nm (inner core antennae, F690), and λf > 700 nm (low energy antenna sites, F720), in addition to the P700. The FDMR spectrum in F690 emission can be interpreted as that of (3)P700, observed via reverse singlet excitation energy transfer and added to the FDMR spectrum of the antenna triplet states generated via intramolecular intersystem crossing. This would indicate that reversible energy transfer between F690 and P700 occurs even at 4.2 K.
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Affiliation(s)
- G F Searle
- Department of Molecular Physics, Agricultural University, Dreijenlaan 3, 6703 HA, Wageningen, The Netherlands
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Matsubara H, Saeki K. Structural and Functional Diversity of Ferredoxins and Related Proteins. ADVANCES IN INORGANIC CHEMISTRY 1992. [DOI: 10.1016/s0898-8838(08)60065-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Andersson B, Franzén LG. Chapter 5 The two photosystems of oxygenic photosynthesis. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/s0167-7306(08)60173-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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19
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Isolation and characterization of a cDNA clone encoding an 18-kDa hydrophobic photosystem I subunit (PSI-L) from barley (Hordeum vulgare L.). J Biol Chem 1991. [DOI: 10.1016/s0021-9258(20)89566-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Budil DE, Thurnauer MC. The chlorophyll triplet state as a probe of structure and function in photosynthesis. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1057:1-41. [PMID: 1849002 DOI: 10.1016/s0005-2728(05)80081-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- D E Budil
- Baker Laboratory of Chemistry, Cornell University, Ithaca, NY 14850
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21
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Hoshina S, Sakurai R, Kunishima N, Wada K, Itoh S. Selective destruction of iron-sulfur centers by heat/ethylene glycol treatment and isolation of Photosystem I core complex. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1990. [DOI: 10.1016/0005-2728(90)90216-q] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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22
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Scheller HV, Okkels JS, Høj PB, Svendsen I, Roepstorff P, Møller BL. The primary structure of a 4.0-kDa photosystem I polypeptide encoded by the chloroplast psaI gene. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)51479-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Okkels JS, Scheller HV, Jepsen LB, Møller BL. A cDNA clone encoding the precursor for a 10.2 kDa photosystem I polypeptide of barley. FEBS Lett 1989; 250:575-9. [PMID: 2666162 DOI: 10.1016/0014-5793(89)80799-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Two cDNA clones for the barley photosystem I polypeptide which migrates with an apparent molecular mass of 9.5 kDa on SDS-polyacrylamide gels have been isolated using antibodies and an oligonucleotide probe. The determined N-terminal amino acid sequence for the mature polypeptide confirms the identification of the clones. The 644 base-pair sequence of one of the clones contains one large open reading frame coding for a 14,882 Da precursor polypeptide. The molecular mass of the mature polypeptide is 10 193 Da. The hydropathy plot of the polypeptide shows one membranespanning region with a predicted alpha-helix secondary structure. The gene for the 9.5 kDa polypeptide has been designated PsaH.
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Affiliation(s)
- J S Okkels
- Department of Plant Physiology, Royal Veterinary and Agricultural University, Frederiksberg C, Denmark
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Scheller HV, Svendsen I, Møller BL. Subunit Composition of Photosystem I and Identification of Center X as a [4Fe-4S] Iron-Sulfur Cluster. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)83520-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Guigliarelli B, Guillaussier J, Bertrand P, Gayda JP, Setif P. Evidence for Only One Iron-Sulfur Cluster in Center X of Photosystem I from Higher Plants. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)83306-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Refined analysis of the trimeric structure of the isolated Photosystem I complex from the thermophilic cyanobacterium Synechococcus sp. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1989. [DOI: 10.1016/s0005-2728(89)80168-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Vainstein A, Peterson CC, Thornber JP. Light-harvesting Pigment-Proteins of Photosystem I in Maize. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(19)84961-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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29
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Scheller HV, Svendsen I, Møller BL. Amino acid sequence of the 9-kDa iron-sulfur protein of photosystem I in barley. CARLSBERG RESEARCH COMMUNICATIONS 1989; 54:11-5. [PMID: 2665764 DOI: 10.1007/bf02910468] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The 9-kDa thylakoid polypeptide which in vivo carries the iron-sulfur centers A and B of photosystem I was isolated from barley (Hordeum vulgare L.) and the complete amino acid sequence determined. The polypeptide shows a very high degree of homology with the corresponding polypeptides in other plant species. The polypeptide is not post-translationally processed except for the removal of the N-terminal formyl-methionine and the insertion of the iron-sulfur centers.
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Affiliation(s)
- H V Scheller
- Department of Plant Physiology, Royal Veterinary and Agricultural University, Frederiksberg C
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30
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31
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Münch S, Ljungberg U, Steppuhn J, Schneiderbauer A, Nechushtai R, Beyreuther K, Herrmann RG. Nucleotide sequences of cDNAs encoding the entire precursor polypeptides for subunits II and III of the photosystem I reaction center from spinach. Curr Genet 1988; 14:511-8. [PMID: 3066511 DOI: 10.1007/bf00521277] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Several cDNA clones encoding the complete subunit II and III precursor polypeptides of the photosystem I reaction center were isolated from two spinach lambda gt1 1 expression libraries by immunoscreening and homologous hybridization. The identity of the recombinant cDNAs was verified by an N-terminal amino acid sequence of 14 and 20 residues for the respective mature spinach proteins. The ca. 880 nucleotide long sequence and derived amino acid sequence for subunit II predict a precursor of 23.2 kDa (212 residues) and a positively charged, mature protein of 17.9 kDa (162 residues). The corresponding data for subunit III are ca. 710 nucleotides (cDNA), 13.4 kDa (125 residues, precursor polypeptide) and, again, a positively charged, mature protein of 9.7 kDa (91 residues). Secondary structure predictions indicate that both subunits are extramembraneous components of photosystem I. Subunit II is probably located on the matrix-side, subunit III in the lumen of stroma lamellae which is consistent both with biochemical findings and the proposed roles of these proteins in the electron transition from and to photosystem I, respectively. Major transcripts of 1.1 kb (subunit II) and 0.8 kb (subunit III) have been observed by RNA-DNA hybridization.
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Affiliation(s)
- S Münch
- Botanisches Institut der Ludwig-Maximilians-Universität München, Federal Republic of Germany
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32
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Riethman H, Bullerjahn G, Reddy KJ, Sherman LA. Regulation of cyanobacterial pigment-protein composition and organization by environmental factors. PHOTOSYNTHESIS RESEARCH 1988; 18:133-161. [PMID: 24425163 DOI: 10.1007/bf00042982] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/1987] [Accepted: 12/24/1987] [Indexed: 06/03/2023]
Abstract
The coordinate expression of stress-specific genes is a common response of all organisms to altered environmental conditions. In cyanobacteria, the physiological consequences of stress are often reflected in both the ultrastructure of the cell and in photosynthesis-related properties. This review will focus on the alterations in cyanobacterial pigment-protein organization which occur under different growth conditions, and how several molecular genetic aproaches are being used in this laboratory to investigate the regulatory mechanisms underlying these alterations. We will discuss in detail the response to iron starvation, and present a testable hypothesis for the mechanism of thylakoid reorganization mediated by this response.
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Affiliation(s)
- H Riethman
- Division of Biological Sciences, University of Missouri, Tucker Hall, 65211, Columbia, MO, USA
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33
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Okkels JS, Jepsen LB, Hønberg LS, Lehmbeck J, Scheller HV, Brandt P, Høyer-Hansen G, Stummann B, Henningsen KW, von Wettstein D. A cDNA clone encoding a 10.8 kDa photosystem I polypeptide of barley. FEBS Lett 1988; 237:108-12. [PMID: 3049147 DOI: 10.1016/0014-5793(88)80181-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A cDNA clone encoding the barley photosystem I polypeptide which migrates with an apparent molecular mass of 16 kDa on SDS-polyacrylamide gels has been isolated. The 634 bp sequence of this clone has been determined and contains one large open reading frame coding for a 15,457 Da precursor polypeptide. The molecular mass of the mature polypeptide is 10,821 Da. The amino acid sequence of the transit peptide indicates that the polypeptide is routed towards the stroma side of the thylakoid membrane. The hydropathy plot of the polypeptide shows no membrane-spanning regions.
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Affiliation(s)
- J S Okkels
- Department of Plant Physiology, Royal Veterinary and Agricultural University, Frederiksberg C, Denmark
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34
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Steppuhn J, Hermans J, Nechushtai R, Ljungberg U, Thümmler F, Lottspeich F, Herrmann RG. Nucleotide sequence of cDNA clones encoding the entire precursor polypeptides for subunits IV and V of the photosystem I reaction center from spinach. FEBS Lett 1988; 237:218-24. [PMID: 3049152 DOI: 10.1016/0014-5793(88)80205-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Using lambda gt11 expression cloning and immunoscreening, cDNA-containing recombinant phages for subunits IV and V of the photosystem I reaction center were isolated, sequenced and used to probe Northern blots of polyadenylated RNA prepared from spinach seedlings. The mRNA sizes for both components are approximately 1000 and 850 nucleotides, respectively. The 968 nucleotide cDNA sequence and derived amino acid sequence for subunit IV predict a single open reading frame of 231 amino acid residues (25.4 kDa). Comparison with a 13-residue N-terminal amino acid sequence determined for subunit IV suggests a mature protein of 17.3 kDa (154 residues) and a transit sequence of 77 amino acids (8.1 kDa). The corresponding data for subunit V are 677 bp (cDNA), 167 residues for the precursor protein (18.2 kDa), 98 residues for the mature polypeptide (10.8 kDa) and 69 residues for the transit peptide (7.4 kDa). Secondary structure predictions indicate that both proteins possess greatly different transit sequences and that none is membrane-spanning.
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Affiliation(s)
- J Steppuhn
- Botanisches Institut der Ludwig-Maximilians-Universität, München, FRG
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35
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Hoffman NE, Pichersky E, Malik VS, Ko K, Cashmore AR. Isolation and sequence of a tomato cDNA clone encoding subunit II of the photosystem I reaction center. PLANT MOLECULAR BIOLOGY 1988; 10:435-445. [PMID: 24277591 DOI: 10.1007/bf00014949] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/1987] [Accepted: 01/20/1988] [Indexed: 06/02/2023]
Abstract
We report here the isolation and nucleotide sequence of a cDNA clone encoding a phtosystem I polypeptide that is recognized by a polyclonal antibody prepared against subunit II of the photosystem I reaction center. The transit peptide processing site was determined to occur after Met50 by N terminal sequencing. The decuced sequence of this protein predicts that the polypeptide has a net positive charge (pI=9.6) and no membrane spanning regions are evident from the hydropathy plot. Based on these considerations and the fact that subunit II is solubilized by alkali treatment of thylakoids, we concluded that subunit II is an extrinsic membrane protein. The absence of hydrophobic regions characteristic of thylakoid transfer domains furthermore implies that subunit II is localized on the stromal side of the membrane.
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Affiliation(s)
- N E Hoffman
- Plant Science Institute, Department of Biology, University of Pennsylvania, 19104, Philadelphia, PA, USA
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36
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37
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Abstract
Apart from the 8 kDa subunit, which is of chloroplast origin, most of the small polypeptides of the PS I reaction center from higher plants are encoded in nuclear genes. We describe here the first nucleotide sequence of a nuclear component of this photosystem, the precursor of the 20 kDa protein. The deduced sequence of the large transit peptide (55-60 amino acids) is rich in serine/threonine residues and has a net positive charge, which are classical features of these precursors. The sequence itself is mainly hydrophilic, with no possibility of classical membrane-spanning alpha-helices; it exhibits an interesting stretch of five basic amino acids in close vicinity: Thr-Arg-Leu-Arg-Ser-Lys-Tyr-Lys-Ile-Lys-Tyr.
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Affiliation(s)
- B Lagoutte
- Département de Biologie, CEN Saclay, Gif-sur-Yvette, France
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38
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39
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Dunn PP, Gray JC. Localization and nucleotide sequence of the gene for the 8 kDa subunit of photosystem I in pea and wheat chloroplast DNA. PLANT MOLECULAR BIOLOGY 1988; 11:311-319. [PMID: 24272344 DOI: 10.1007/bf00027388] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/1988] [Accepted: 06/02/1988] [Indexed: 06/02/2023]
Abstract
The gene for the 8 kDa subunit of photosystem I has been located in the small single copy region of wheat chloroplast DNA by coupled transcription-translation of cloned fragments of DNA and by DNA sequence analysis. The pea gene for this subunit was located in pea chloroplast DNA by using the wheat gene as a probe. The location was confirmed by immunoprecipitation of the products of coupled transcription-translation of cloned DNA with antiserum raised against the small subunits of pea photosystem I and by DNA sequence analysis. The deduced amino acid sequences of the pea and wheat proteins are identical in seventy-six out of the eighty-one amino acid residues. There are nine conserved cysteine residues, eight of which are arranged in the primary structure in a similar way to those in bacterial ferredoxins containing two 4Fe-4S centres, suggesting that the polypeptide binds iron sulphur centres A and B of photosystem I.
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Affiliation(s)
- P P Dunn
- Botany School, University of Cambridge, Downing Street, CB2 3EA, Cambridge, UK
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40
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Scheller HV, Høj PB, Svendsen I, Møller BL. Partial amino acid sequences of two nuclear-encoded Photosystem I polypeptides from barley. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1988. [DOI: 10.1016/0005-2728(88)90085-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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41
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An interpretation of the peculiar magnetic properties of center X in Photosystem I in terms of a 2Fe-2S cluster. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1988. [DOI: 10.1016/0005-2728(88)90048-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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42
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Dunn PP, Packman LC, Pappin D, Gray JC. N-terminal amino acid sequence analysis of the subunits of pea photosystem I. FEBS Lett 1988; 228:157-61. [PMID: 3277857 DOI: 10.1016/0014-5793(88)80607-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Six 'core' subunits of pea photosystem I have been isolated and their N-terminal amino acid sequences determined by gas-phase or solid-phase sequencing. On average more than thirty residues were determined from the N-terminus of each polypeptide. This sequence analysis has revealed three polypeptides with charged N-terminal regions (21, 17 and 11 kDa subunits), one polypeptide with a predominantly hydrophobic N-terminal region (9 kDa subunit), one polypeptide which is cysteine-rich (8 kDa subunit) and one which is alanine-rich (13 kDa subunit).
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Affiliation(s)
- P P Dunn
- Department of Botany, University of Cambridge, England
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43
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Bassi R, Giacometti G, Simpson DJ. Characterisation of stroma membranes from Zea mays L. chloroplasts. ACTA ACUST UNITED AC 1988. [DOI: 10.1007/bf02904409] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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44
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Reilly P, Nelson N. Photosystem I complex. PHOTOSYNTHESIS RESEARCH 1988; 19:73-84. [PMID: 24425369 DOI: 10.1007/bf00114570] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/1987] [Accepted: 03/30/1988] [Indexed: 06/03/2023]
Abstract
Photosystem I is an integral component of the thylakoid membrane which catalyzes the photoreduction of ferredoxin using plastocyanin or cytochrome c as electron donor. In higher plants, the photosystem I complex is composed of eight protein subunits, chlorophyll a, carotenoids, phylloquinone and bound iron sulfur clusters. The molecular biology and biochemistry of the complex are discussed in relation to the structure and function of the individual components. The mechanisms involved in the assembly of the components into a functional complex are also discussed.
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Affiliation(s)
- P Reilly
- Roche Research Center, Roche Institute of Molecular Biology, 07110, Nutley, New Jersey, USA
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45
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Zanetti G, Merati G. Interaction between photosystem I and ferredoxin. Identification by chemical cross-linking of the polypeptide which binds ferredoxin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1987; 169:143-6. [PMID: 2824198 DOI: 10.1111/j.1432-1033.1987.tb13591.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Ferredoxin has been effectively cross-linked to photosystem I complex by treatment of purified particles or thylakoids with N-ethyl-3-(3-dimethylaminopropyl)carbodiimide, a zero-length cross-linker which stabilizes protein-protein electrostatic interactions. Analysis of photosystem I polypeptide composition after such a treatment showed a specific decrease of the 20-kDa subunit and the appearance of a new component of about 42 kDa which was recognized by the anti-ferredoxin antibody. Cross-linking of ferredoxin to thylakoids allowed the membrane preparation to photoreduce cytochrome c without requiring exogenous ferredoxin, whereas photosystem I particles purified from treated thylakoids were inactivated in the NADP+ photoreduction activity. From these results, it can be inferred that the polypeptide of 20 kDa is the photosystem I subunit which interacts with ferredoxin during the photosynthetic electron transport.
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Affiliation(s)
- G Zanetti
- Dipartimento di Fisiologia e Biochimica Generali, Italy
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46
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Identification of a chloroplast-encoded 9-kDa polypeptide as a 2[4Fe-4S] protein carrying centers A and B of photosystem I. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)45260-x] [Citation(s) in RCA: 124] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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47
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Photosystem I charge separation in the absence of center A and B. III. Biochemical characterization of a reaction center particle containing P-700 and FX. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1987. [DOI: 10.1016/0005-2728(87)90034-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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48
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Cantrell A, Bryant DA. Molecular cloning and nucleotide sequence of the psaA and psaB genes of the cyanobacterium Synechococcus sp. PCC 7002. PLANT MOLECULAR BIOLOGY 1987; 9:453-468. [PMID: 24277132 DOI: 10.1007/bf00015877] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/1987] [Accepted: 07/14/1987] [Indexed: 06/02/2023]
Abstract
The psaA and psaB genes, which encode the P700 chlorophyll a apoproteins of the Photosystem I complex, have been cloned from the unicellular, transformable cyanobacterium Synechococcus sp. PCC 7002. The nucleotide sequence of these genes and of their flanking sequences have been determined by the chain termination method. As found in the chloroplast genomes of higher plants, the psaA gene lies 5' to the psaB gene; however, the cyanobacterial genes are separated by a greater distance (173 vs. 25-26 bp). The psaA gene is predicted to encode a polypeptide of 739 amino acid residues (81.7 kDa), and the psaB gene is predicted to encode a polypeptide of 733 residues (81.4 kDa). The cyanobacterial psa gene products are 76% to 81% identical to their higher plant homologues; moreover, because of conservative amino acid replacements, the cyanobacterial sequences are more than 95% homologous to those determined for higher plants. These results provide the basis for a genetic analysis of Photosystem I, and are discussed in relationship to structural and functional aspects of the Photosystem I complexes of both cyanobacteria and higher plants.
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Affiliation(s)
- A Cantrell
- S-101 Frear Bldg. Department of Molecular and Cell Biology, The Pennsylvania State University, 16802, University Park, PA, USA
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49
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Golbeck JH. Light-induced charge separation across the photosynthetic membrane: a proposed structure for the photosystem I reaction center. J Memb Sci 1987. [DOI: 10.1016/s0376-7388(00)80374-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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50
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Høj PB, Møller BL. Acid-labile sulfide and zero-valence sulfur in plant extracts containing chlorophyll and ionic detergents. Anal Biochem 1987; 164:307-14. [PMID: 3674379 DOI: 10.1016/0003-2697(87)90498-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Two methods for analysis of acid-labile sulfide and zero-valence sulfur in plant extracts containing chlorophyll as well as ionic and/or nonionic detergents are presented. Both methods are based on the conversion of sulfide into methylene blue. In the first method an ethyl acetate extraction step is used to remove chlorophyll and its degradation products which otherwise prevent spectrophotometric quantitation of methylene blue. The second assay method employs 35S-labeled plant extracts. This method, which involves thin-layer chromatography and autoradiography, is potentially more sensitive than the spectrophotometric assay in detecting acid-labile sulfide and zero-valence sulfur.
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Affiliation(s)
- P B Høj
- Department of Plant Physiology, Royal Veterinary and Agricultural University, Frederiksberg C, Denmark
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