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Molecular orientation of factor VIIIa on the phospholipid membrane surface determined by fluorescence resonance energy transfer. Biochem J 2013; 452:293-301. [PMID: 23521092 DOI: 10.1042/bj20130025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
F (Factor) VIIIa binds to phospholipid membranes during formation of the FXase complex. Free thiols from cysteine residues of isolated FVIIIa A1 and A2 subunits and the A3 domain of the A3C1C2 subunit were labelled with PyMPO maleimide {1-(2-maleimidylethyl)-4-[5-(4-methoxyphenyl)-oxazol-2-yl]pyridinium methanesulfonate} or fluorescein (fluorescence donors). Double mutations of the A3 domain (C2000S/T1872C and C2000S/D1828C) were also produced to utilize Cys(1828) and Cys(1872) residues for labelling. Labelled subunits were reacted with complementary non-labelled subunits to reconstitute FVIIIa. Octadecylrhodamine incorporated into phospholipid vesicles was used as an acceptor for distance measurements between FVIII residues and membrane surface by fluorescence resonance energy transfer. The results of the present study indicate that a FVIII axis on a plane that intersects the approximate centre of each domain is orientated with a tilt angle of ~30-50° on the membrane surface. This orientation predicted the existence of contacts mediated by residues 1713-1725 in the A3 domain in addition to a large area of contacts within the C domains. FVIII variants where Arg(1719) or Arg(1721) were mutated to aspartate showed a >40-fold reduction in membrane affinity. These results identify possible orientations for FVIIIa bound to the membrane surface and support a new interaction between the A3 domain and the membrane probably mediated in part by Arg(1719) and Arg(1721).
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Buranda T, Wu Y, Perez D, Chigaev A, Sklar LA. Real-time partitioning of octadecyl rhodamine B into bead-supported lipid bilayer membranes revealing quantitative differences in saturable binding sites in DOPC and 1:1:1 DOPC/SM/cholesterol membranes. J Phys Chem B 2010; 114:1336-49. [PMID: 20043651 DOI: 10.1021/jp906648q] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quantitative analysis of the staining of cell membranes with the cationic amphiphile, octadecyl rhodamine B (R18), is confounded by probe aggregation and changes to the probes' absorption cross section and emission quantum yield. In this paper, flow cytometry, quantum-dot-based fluorescence calibration beads, and FRET were used to examine real-time transfer of R18 from water to two limiting models of the cellular plasma membrane, namely, a single-component disordered membrane, dioleoyl-L-alpha-phosphatidylcholine (DOPC), and a ternary mixture of DOPC, cholesterol, and sphingomyelin (DSC) membranes, reconstituted on spherical and monodisperse glass beads (lipobeads). The quenching of R18 was analyzed as the probe concentration was raised from 0 to 10 mol % in membranes. The data show a > 2-fold enhancement in the quenching level of the probes that were reconstituted in DSC relative to DOPC membranes at the highest concentration of R18. We have parametrized the propagation of concentration-dependent quenching as a function of real-time binding of R18 to lipobeads. In this way, phenomenological kinetics of serum-albumin-mediated transfer of R18 from the aqueous phase to DOPC and DSC membranes could be evaluated under optimal conditions where the critical aggregation concentration (CAC) of the probe is defined as 14 nM. The mass action kinetics of association of R18 with DOPC and DSC lipobeads are shown to be similar. However, the saturable capacity for accepting exogenous probes is found to be 37% higher in DOPC relative to that for DSC membranes. The difference is comparable to the disparity in the average molecular areas of DOPC and DSC membranes. Finally, this analysis shows little difference in the spectral overlap integrals of the emission spectrum of a fluorescein derivative donor and the absorption spectrum of either monomeric or simulated spectrum of dimeric R18. This approach represents a first step toward a nanoscale probing of membrane heterogeneity in living cells by analyzing differential local FRET among sites of unique receptor expression in living cells.
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Affiliation(s)
- Tione Buranda
- Department of Pathology and Cancer Center, University of New Mexico School of Medicine, Albuquerque, New Mexico 87131, USA.
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3
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Mukhopadhyay J, Mekler V, Kortkhonjia E, Kapanidis AN, Ebright YW, Ebright RH. Fluorescence resonance energy transfer (FRET) in analysis of transcription-complex structure and function. Methods Enzymol 2003; 371:144-59. [PMID: 14712697 DOI: 10.1016/s0076-6879(03)71010-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jayanta Mukhopadhyay
- Waksman Institute, Howard Hughes Medical Institute, Rutgers University, 190 Frelinghuysen Road, Piscataway, New Jersey 08854, USA
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4
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Hasselbacher CA, Dewey TG. Changes in retinal position during the bacteriorhodopsin photocycle: a resonance energy-transfer study. Biochemistry 2002. [DOI: 10.1021/bi00368a060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Groth G, Schirwitz K. Rapid purification of membrane extrinsic F1-domain of chloroplast ATP synthase in monodisperse form suitable for 3D-crystallization. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 260:15-21. [PMID: 10091579 DOI: 10.1046/j.1432-1327.1999.00101.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A new chromatographic procedure for purification of the membrane extrinsic F1-domain of chloroplast ATP synthase is presented. The purification is achieved by a single anion exchange chromatography step. Determination of the enzyme-bound nucleotides reveals only 1 mole of ADP per complex. The purified enzyme shows a latent Ca(2+)-dependent ATPase activity of 1.0 mumol.mg-1 min-1 and a Mg(2+)-dependent activity of 4.4 mumol.mg-1 .min-1. Both activities are increased up to 8-10-fold after dithiothreitol activation. Analysis of the purified F1-complex by SDS/PAGE, silver staining and immunoblotting revealed that the preparation is uncontaminated by fragmented subunits or ribulose-1,5-bisphosphate carboxylase/oxygenase. Gel filtration experiments indicate that the preparation is homogenous and monodisperse. In order to determine the solubility minimum of the purified F1-complex the isoelectric point of the preparation was calculated from pH mapping on ion exchange columns. In agreement with calculations based on the amino acid sequence, a slightly acidic pI of 5.7 was found. Using ammonium sulphate as a precipitant the purified CF1-complex could be crystallized by MicroBatch.
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Affiliation(s)
- G Groth
- Heinrich-Heine-Universität Düsseldorf, Biochemie der Pflanzen, Germany.
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6
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Cheng X, Lee JC. Interactive and dominant effects of residues 128 and 141 on cyclic nucleotide and DNA bindings in Escherichia coli cAMP receptor protein. J Biol Chem 1998; 273:705-12. [PMID: 9422721 DOI: 10.1074/jbc.273.2.705] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The molecular events in the cAMP-induced allosteric activation of cAMP receptor protein (CRP) involve interfacial communications between subunits and domains. However, the roles of intersubunit and interdomain interactions in defining the selectivity of cAMP against other cyclic nucleotides and cooperativity in ligand binding are still not known. Natural occurring CRP mutants with different phenotypes were employed to address these issues. Thermodynamic analyses of subunit association, protein stability, and cAMP and DNA binding as well as conformational studies of the mutants and wild-type CRPs lead to an identification of the apparently dominant roles of residues 128 and 141 in the cAMP-modulated DNA binding activity of CRP. Serine 128 and the C-helix were implicated as playing a critical role in modulating negative cooperativity of cyclic nucleotide binding. A correlation was established between a weak affinity for subunit assembly and the relaxation of cyclic nucleotide selectivity in the G141Q and S128A/G141Q mutants. These results imply that intersubunit interaction is important for cyclic nucleotide discrimination in CRP. The double mutant S128A/G141Q, constructed from two single mutations of S128A and G141Q, which exhibit opposite phenotypic characteristics of CRP- and CRP*, respectively, assumes a CRP* phenotype and has biochemical properties similar to those of the G141Q mutant. These observations suggest that mutation G141Q exerts a dominant effect over mutation S128A and that the subunit realignment induced by the G141Q mutation can override the local structural disruption created by mutation S128A.
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Affiliation(s)
- X Cheng
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch at Galveston, Galveston, Texas 77555-1055, USA
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7
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McCallum CD, Su B, Neuenschwander PF, Morrissey JH, Johnson AE. Tissue factor positions and maintains the factor VIIa active site far above the membrane surface even in the absence of the factor VIIa Gla domain. A fluorescence resonance energy transfer study. J Biol Chem 1997; 272:30160-6. [PMID: 9374497 DOI: 10.1074/jbc.272.48.30160] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Coagulation factor VIIa (fVIIa), a soluble serine protease, exhibits full proteolytic activity only when bound to its cofactor, tissue factor (TF). Both proteins interact with membranes; TF is an integral membrane protein, while fVIIa binds reversibly to phospholipid surfaces via its Gla domain. In this study, we examine the extent to which the location of the fVIIa active site in the fVIIa.TF complex is determined by the fVIIa Gla domain. A fluorescein dye was covalently attached to the active site of fVIIa lacking the Gla domain (Gla domainless fVIIa, GD-fVIIa) via a tripeptide tether to yield fluorescein-D-Phe-Pro-Arg-GD-fVIIa (Fl-FPR-GD-fVIIa). The location of the active site of GD-fVIIa relative to the membrane surface was determined using fluorescence resonance energy transfer between the fluorescein dye in the active site of GD-fVIIa and octadecylrhodamine (OR) at the surface of phospholipid vesicles. As expected, no energy transfer was observed between Fl-FPR-GD-fVIIa and OR in vesicles composed of phosphatidylcholine/phosphatidylserine (PC/PS, 4:1) because the Gla domain is required for the binding of fVIIa to phospholipid. However, when Fl-FPR-GD-fVIIa was titrated with PC or PC/PS vesicles into which purified TF had been reconstituted, energy transfer was observed. Based on the dependence of fluorescence resonance energy transfer on OR density, the average distance of closest approach between fluorescein in the active site of Fl-FPR-GD-fVIIa.TF and OR at the vesicle surface was determined to be 78 A (kappa2 = (2)/(3)). Since this value is nearly the same as that obtained with intact Fl-FPR-fVIIa bound to TF, the presence or absence of the fVIIa Gla domain has only a small effect on the location of the active site in the fVIIa.TF complex. The extracellular domain of tissue factor therefore must be fairly rigid and fixed relative to the surface to position and maintain the fVIIa active site far above the membrane even in the absence of the fVIIa Gla domain.
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Affiliation(s)
- C D McCallum
- Department of Medical Biochemistry and Genetics, Texas A & M University, College Station, Texas 77843, USA.
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8
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Yegneswaran S, Wood GM, Esmon CT, Johnson AE. Protein S alters the active site location of activated protein C above the membrane surface. A fluorescence resonance energy transfer study of topography. J Biol Chem 1997; 272:25013-21. [PMID: 9312108 DOI: 10.1074/jbc.272.40.25013] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The location of the active site of membrane-bound activated protein C (APC) relative to the phospholipid surface was determined both in the presence and absence of its cofactor, protein S, using fluorescence resonance energy transfer (FRET). APC was chemically modified to create the FRET donor species, Fl-FPR-APC, with a fluorescein dye (Fl) covalently attached to the active site via a D-Phe-Pro-Arg (FPR) tether and located in the active site near S4. FRET was observed when Fl-FPR-APC was titrated in the presence of Ca2+ ions with phosphatidylcholine/phosphatidylserine (4:1) vesicles containing the FRET acceptor, octadecylrhodamine (OR). Assuming a random orientation of transition dipoles (kappa2 = 2/3), the average distance of closest approach between the fluorescein in the active site of the membrane-bound APC and the OR at the membrane surface is 94 A. The same calcium-dependent distance was obtained for both small and large unilamellar vesicles and for vesicles that contained phosphatidylethanolamine. The active site of membrane-bound APC is therefore located far above the phospholipid surface. Upon addition of protein S, the efficiency of Fl-FPR-APC to OR energy transfer increased due to a protein S-dependent rotational and/or translational movement of the APC protease domain relative to the surface. If this movement were solely translational, then the average height of the fluorescein in the membrane-bound APC.protein S complex would be 84 A above the surface. The extent of Fl-FPR-APC to OR energy transfer was unaltered by the addition of thrombin-inactivated protein S. The protein S effect was also specific for APC, since the addition of protein S to similarly-labeled derivatives of factor Xa, factor IXa, or factor VIIa did not alter the locations of their active sites. This direct measurement demonstrates that the binding of the protein S cofactor to its cognate enzyme elicits a relocation of the active site of APC relative to the membrane surface and thereby provides a structural explanation for the recently observed protein S-dependent change in the site of factor Va cleavage by APC.
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Affiliation(s)
- S Yegneswaran
- Department of Medical Biochemistry & Genetics, Texas A&M University Health Science Center, College Station, Texas 77843-1114, USA
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9
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McCallum CD, Hapak RC, Neuenschwander PF, Morrissey JH, Johnson AE. The location of the active site of blood coagulation factor VIIa above the membrane surface and its reorientation upon association with tissue factor. A fluorescence energy transfer study. J Biol Chem 1996; 271:28168-75. [PMID: 8910432 DOI: 10.1074/jbc.271.45.28168] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The topography of membrane-bound blood coagulation factor VIIa (fVIIa) was examined by positioning a fluorescein dye in the active site of fVIIa via a tripeptide tether to yield fluorescein-D-phenylalanyl-L-prolyl-L-arginyl-fVIIa (Fl-FPR-fVIIa). The location of the active-site probe relative to the membrane surface was determined, both in the presence and absence of tissue factor (TF), using fluorescence energy transfer between the fluorescein dye and octadecylrhodamine (OR) at the phospholipid vesicle surface. When Fl-FPR-fVIIa was titrated with phospholipid vesicles containing OR, the magnitude of OR-, calcium ion-, and phosphatidylserine-dependent fluorescence energy transfer revealed that the average distance of closest approach between fluorescein in the active site of fVIIa and OR at the vesicle surface is 82 A assuming a random orientation of donor and acceptor dyes (kappa2 = 2/3; the orientational uncertainty totals approximately 10%). The active site of fVIIa is therefore located far above the membrane surface, and the elongated fVIIa molecule must bind at one end to the membrane and project approximately perpendicularly out of the membrane. When Fl-FPR-fVIIa was titrated with vesicles that contained TF, the efficiency of energy transfer was increased by a TF-dependent translational and/or rotational movement of the fVIIa protease domain relative to the membrane surface. If this movement was solely translational, the height of the active site of fVIIa was lowered by an average of 6 A after binding to TF. The association of fVIIa with TF on the membrane surface therefore causes a significant reorientation of the active site relative to the membrane surface. This cofactor-dependent realignment of the active-site groove presumably facilitates and optimizes fVIIa cleavage of its membrane-bound substrates.
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Affiliation(s)
- C D McCallum
- Department of Medical Biochemistry & Genetics, Texas A&M University Health Science Center, College Station, Texas 77843-1114, USA.
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10
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Chloroplast ATP synthase: the clutch between proton flow and ATP synthesis is at the interface of subunit γ and CF1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1996. [DOI: 10.1016/0005-2728(96)00004-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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Komatsu-Takaki M. Effects of Energization and Substrates on the Reactivities of Lysine Residues of the Chloroplast ATP Synthase beta Subunit. ACTA ACUST UNITED AC 1995. [DOI: 10.1111/j.1432-1033.1995.tb20259.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Boyer PD. The binding change mechanism for ATP synthase--some probabilities and possibilities. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1140:215-50. [PMID: 8417777 DOI: 10.1016/0005-2728(93)90063-l] [Citation(s) in RCA: 715] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- P D Boyer
- Department of Chemistry and Biochemistry, University of California, Los Angeles 90024-1570
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13
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The active site of factor IXa is located far above the membrane surface and its conformation is altered upon association with factor VIIIa. A fluorescence study. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)41886-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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14
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Heyduk T, Lee JC. Solution studies on the structure of bent DNA in the cAMP receptor protein-lac DNA complex. Biochemistry 1992; 31:5165-71. [PMID: 1606140 DOI: 10.1021/bi00137a011] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cyclic AMP receptor protein is involved in the regulation of more than 20 genes. A step in the mechanism of activation of transcription is to induce a significant bending of the DNA upon complex formation between specific DNA and the protein. The induced DNA bending and a structure of the protein-DNA complex were studied by fluorescence energy transfer in 50 mM Tris, 1 mM EDTA, and 50 mM KCl at pH 7.8 and 20 degrees C. The symmetry of the DNA bend was estimated by measuring the efficiency of transfer between the protein and a label on either the upstream or the downstream end of a lac DNA fragment. The results show that the bend, despite the asymmetry in the DNA sequence, is symmetrical, for the fragments which length ranges from 26 to 40 bp. Using fluorescence energy transfer, the extent of DNA bending was estimated by measuring the end-to-end distance of the DNA fragment which was labeled with a donor-acceptor pair on two opposite ends. Both steady-state and time-resolved measurements showed that in a 26 bp lac DNA fragment complexed with cyclic AMP receptor protein, the end-to-end distance is about 77 A which corresponds to a bending angle of 80 degrees or 100 degrees, depending on the actual contour length between the fluorophores in the free DNA fragment. The results using longer DNA fragments show no measurable amount of energy transfer; thus, it is very unlikely that the DNA completely wraps around the CRP molecule.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T Heyduk
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77550
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15
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Energy-dependent changes in conformation and catalytic activity of the chloroplast ATP synthase. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)45886-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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16
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Fluorescence resonance energy transfer mapping of the fourth of six nucleotide-binding sites of chloroplast coupling factor 1. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(19)47370-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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17
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Hopkins WG. Effect of low growth temperature on coupling between electron transport and proton flux in Vicia faba thylakoids. PHYSIOLOGIA PLANTARUM 1990; 79:649-655. [PMID: 21087274 DOI: 10.1111/j.1399-3054.1990.tb00039.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Coupling between electron transport and proton flux has been compared in chloroplasts from Vicia faba (cv. Windsor) plants grown at 20 and 5°C. Proton uptake by warm-grown thylakoids was sensitive to external pH and stimulated by micromolar adenine nucleotide above pH 7.0. Electron transport was modulated by pH, adenine nucleotide and energy transfer inhibitors (triphenyltin and Hg(2+) ). By contrast, proton uptake by cold-grown thylakoids was generally lower and was insensitive to micromolar ATP. The rate of non-phosphorylating electron flow in cold-grown thylakoids was relatively insensitive to pH and Hg(2+) and was not modulated by adenine nucleotides or triphenyltin. Stimulation of electron transport by phosphorylating conditions in cold-grown thylakoids was generally lower and insensitive to pH. It is concluded that the control of proton efflux through CF(0) -CF(1) differs in thylakoids of V. faba grown at warm and cold temperatures.
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Affiliation(s)
- W G Hopkins
- Dept of Plant Sciences, Univ. of Western Ontario, London, Ontario, Canada N6A 5B7
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18
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Musier-Forsyth KM, Hammes GG. Rotational dynamics of chloroplast ATP synthase in phospholipid vesicles. Biochemistry 1990; 29:3236-41. [PMID: 2159333 DOI: 10.1021/bi00465a014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The rotational dynamics of the purified dicyclohexylcarbodiimide-sensitive H(+)-ATPase (DSA) reconstituted into phospholipid vesicles and of the DSA coreconstituted with the proton pump bacterio-rhodopsin were examined by using the technique of time-resolved phosphorescence emission anisotrophy. The phosphorescent probe erythrosin isothiocyanate was used to covalently label the gamma-polypeptide of DSA before reconstitution. Rotational correlation times were measured under a variety of conditions. The rotational correlation time was independent of the viscosity of the external medium but increased significantly as the microviscosity of the membrane increased. This indicates the rotational correlation times are a measure of the enzyme motion within the membrane. The activation energy associated with the rotational correlation time is 8-10 kcal/mol. At 4 degrees C, the correlation time, typically approximately 100-180 microseconds, was unaffected by the addition of substrates and the presence of a membrane pH gradient. Therefore, molecular rotation of the DSA does not appear to play an important role in enzyme catalysis or ion pumping.
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Affiliation(s)
- K M Musier-Forsyth
- Department of Chemistry, Cornell University, Ithaca, New York 14853-1301
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19
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The active site of membrane-bound meizothrombin. A fluorescence determination of its distance from the phospholipid surface and its conformational sensitivity to calcium and factor Va. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39312-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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20
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Chattopadhyay A. Chemistry and biology of N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-labeled lipids: fluorescent probes of biological and model membranes. Chem Phys Lipids 1990; 53:1-15. [PMID: 2191793 DOI: 10.1016/0009-3084(90)90128-e] [Citation(s) in RCA: 280] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Lipids that are covalently labeled with the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group are widely used as fluorescent analogues of native lipids in model and biological membranes to study a variety of processes. The fluorescent NBD group may be attached either to the polar or the apolar regions of a wide variety of lipid molecules. Synthetic routes for preparing the lipids, and spectroscopic and ionization properties of these probes are reviewed in this report. The orientation of various NBD-labeled lipids in membranes, as indicated by the location of the NBD group, is also discussed. The NBD group is uncharged at neutral pH in membranes, but loops up to the surface if attached to acyl chains of phospholipids. These lipids find applications in a variety of membrane-related studies which include membrane fusion, lipid motion and dynamics, organization of lipids and proteins in membranes, intracellular lipid transfer, and bilayer to hexagonal phase transition in liposomes. Use of NBD-labeled lipids as analogues of natural lipids is critically evaluated.
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Affiliation(s)
- A Chattopadhyay
- Department of Biochemistry and Biophysics, University of California, Davis 95616
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21
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Komatsu-Takaki M. Energy-dependent Conformational Changes in the ϵ Subunit of the Chloroplast ATP Synthase (CF0CF1). J Biol Chem 1989. [DOI: 10.1016/s0021-9258(19)84635-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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22
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23
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Shapiro AB, McCarty RE. Alteration of the nucleotide-binding site asymmetry of chloroplast coupling factor 1 by catalysis. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)68199-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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24
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Melese T, Xue ZX, Stempel KE, Boyer PD. Catalytic properties of chloroplast F1-ATPase modified at catalytic or noncatalytic sites by 2-azido adenine nucleotides. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)60641-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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25
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Husten EJ, Esmon CT, Johnson AE. The active site of blood coagulation factor Xa. Its distance from the phospholipid surface and its conformational sensitivity to components of the prothrombinase complex. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)45150-2] [Citation(s) in RCA: 143] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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26
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27
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NALIN CARLOM, NELSON NATHAN. Structure and Biogenesis of Chloroplast Coupling Factor CF0CF1-ATPase. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/b978-0-12-152515-6.50013-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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28
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Isaacs BS, Husten EJ, Esmon CT, Johnson AE. A domain of membrane-bound blood coagulation factor Va is located far from the phospholipid surface. A fluorescence energy transfer measurement. Biochemistry 1986; 25:4958-69. [PMID: 3768326 DOI: 10.1021/bi00365a036] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The larger subunit of blood coagulation factor Va was covalently labeled with iodoacetamido derivatives of fluorescein and rhodamine without loss of functional activity, as measured by either the one-stage clotting assay or the ability to accelerate prothrombin activation in a purified system. The spectral properties of the dyes were not altered by the presence or absence of the smaller subunit of factor Va, Ca2+, prothrombin, factor Xa, or phosphatidylcholine/phosphatidylserine (PC/PS, 4:1) vesicles. When fluorescein-labeled protein (factor VaF) was titrated with PC/PS vesicles containing either octadecylrhodamine or 5-(N-hexadecanoylamino)eosin, fluorescence energy transfer was observed between the protein-bound donor dyes and the acceptor dyes at the outer surface of the phospholipid bilayer. The extent of energy transfer correlated directly with the extent of protein binding to the vesicles monitored by light scattering. The distance of closest approach between the fluorescein on factor Va and the bilayer surface averaged 90 A for the two different acceptors. Association of factor VaF with factor Xa on the phospholipid surface reduced this separation by 7 A, but association with prothrombin did not alter the distance between the labeled domain on factor VaF and the surface. The efficiency of diffusion-enhanced energy transfer between rhodamine-labeled factor Va and terbium dipicolinate entrapped inside PC/PS vesicles was less than 0.01, consistent with the location of the dye far above the inner surface of the vesicle. Thus, a domain of membrane-bound factor Va is located a minimum of 90 A above the phospholipid surface.(ABSTRACT TRUNCATED AT 250 WORDS)
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Fagan MH, Dewey TG. Resonance energy transfer study of membrane-bound aggregates of the sarcoplasmic reticulum calcium ATPase. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(17)35697-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Abstract
This review is focused on some functional characteristics of the chloroplast coupling factor. The structure of the enzyme and the putative role of its subunits are recalled. An attempt is made to discriminate the driving force and the activator effects of the electrochemical proton gradient. Respective roles of delta pH, delta phi, external and internal pH are discussed with regard to mechanistic implications. The hypothesis of a functional switch of the enzyme between two states with better efficiency either in ATP synthesis or in ATP hydrolysis is also examined. A brief survey is made on some problems complicating quantitative studies of energy coupling, such as localized chemiosmosis, delta pH and delta phi computations, and scalar ATPases. The main data on the enzyme activation and the energy-dependent release of tightly bound nucleotides are summarized. The arguments for and against the catalytic competence of theses nucleotides are reviewed. Lastly, some prevailing models of the catalytic mechanism are presented. The relevance of nucleotides binding change events in this process is discussed.
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Richter ML, Snyder B, McCarty RE, Hammes GG. Binding stoichiometry and structural mapping of the epsilon polypeptide of chloroplast coupling factor 1. Biochemistry 1985; 24:5755-63. [PMID: 2867774 DOI: 10.1021/bi00342a011] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fluorescent probes were attached to the single sulfhydryl residue on the isolated epsilon polypeptide of chloroplast coupling factor 1 (CF1), and the modified polypeptide was reconstituted with the epsilon-deficient enzyme. A binding stoichiometry of one epsilon polypeptide per CF1 was obtained. This stoichiometry corresponded to a maximum inhibition of the Ca2+-dependent ATPase activity of the enzyme induced by epsilon removal. Resonance energy transfer between the modified epsilon polypeptide and fluorescent probes attached to various other sites on the enzyme allowed distance measurements between these sites and the epsilon polypeptide. The epsilon-sulfhydryl is nearly equidistant from both the disulfide (23 A) and the dark-accessible sulfhydryl (26 A) of the gamma subunit. Measurement of the distance between epsilon and the light-accessible gamma-sulfhydryl was not possible due to an apparent exclusion of modified epsilon from epsilon-deficient enzyme after modification of the light-accessible site. The distances measured between epsilon and the nucleotide binding sites on the enzyme were 62, 66, and 49 A for sites 1, 2, and 3, respectively. These measurements place the epsilon subunit in close physical proximity to the sulfhydryl-containing domains of the gamma subunit and approximately 40 A from the membrane surface. Enzyme activity measurements also indicated a close association between the epsilon and gamma subunits: epsilon removal caused a marked increase in accessibility of the gamma-disulfide bond to thiol reagents and exposed a trypsin-sensitive site on the gamma subunit. Either disulfide bond reduction or trypsin cleavage of gamma significantly enhanced the Ca2+-ATPase activity of the epsilon-deficient enzyme. Thus, the epsilon and gamma polypeptides of coupling factor 1 are closely linked, both physically and functionally.
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Partial proteolysis as a probe of the conformation of the gamma subunit in activated soluble and membrane-bound chloroplast coupling factor 1. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(17)39104-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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33
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Galmiche JM, Girault G, Lemaire C. STRUCTURE and FUNCTION OF THE COUPLING-FACTOR OF PHOTOPHOSPHORYLATION. Photochem Photobiol 1985. [DOI: 10.1111/j.1751-1097.1985.tb03626.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Abstract
Fluorescence resonance energy transfer measurements have been used to investigate the spatial relationships between the nucleotide binding sites and the gamma-subunit of the H+-ATPase from chloroplasts and the orientation of these sites with respect to the membrane surface. Fluorescent maleimides reacted covalently at specific sulfhydryl sites on the gamma-subunit served as energy donors. One sulfhydryl site can be labeled only under energized conditions on the thylakoid membrane surface (light site). The two gamma-sulfhydryls exposed after catalytic activation served as a second donor site (disulfide site). In one set of experiments, the nucleotide analogue 2'(3')-(trinitrophenyl)adenosine triphosphate, selectively bound at each of the three nucleotide binding sites of the solubilized coupling factor, was used as an energy acceptor; in another, octadecylrhodamine with its acyl chain inserted in the vesicle bilayer and the rhodamine fluorophore exposed along the membrane surface was the energy acceptor. The distance between the sulfhydryl and disulfide sites was also obtained by sequentially labeling the sites with coumarin (donor) and fluorescein (acceptor) maleimide derivatives, respectively. The results indicate that all three nucleotide sites are approximately equal to 50 A from the light-labeled gamma-sulfhydryl. Two of the nucleotide sites are very far from the gamma-disulfide (greater than 74 A), while the third site, which binds nucleotides reversibly under all conditions, is 62 A from this sulfhydryl. The light-labeled sulfhydryl and disulfide sites are about 42-47 A apart. Finally, the distance of closest approach between the membrane surface of the reconstituted system and the gamma-disulfide is 31 A.(ABSTRACT TRUNCATED AT 250 WORDS)
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Characterization of the cysteinyl-containing peptides of the gamma subunit of coupling factor 1. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)39869-1] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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36
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Role of a disulfide bond in the gamma subunit in activation of the ATPase of chloroplast coupling factor 1. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)39868-x] [Citation(s) in RCA: 213] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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37
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Role of the gamma subunit of chloroplast coupling factor 1 in the light-dependent activation of photophosphorylation and ATPase activity by dithiothreitol. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)39870-8] [Citation(s) in RCA: 163] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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