On the spatial organization of hemes and chlorophyll in cytochrome b(6)f. A linear and circular dichroism study
| Autor: | Schoepp, Barbara, Chabaud, Elodie, Breyton, Cécile, Verméglio, André, Popot, Jean-Luc |
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| Přispěvatelé: | Bioénergétique et Ingénierie des Protéines (BIP ), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de biologie physico-chimique des protéines membranaires (LBPC-PM (UMR_7099)), Institut de biologie physico-chimique (IBPC), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Microbiologie Environnementale et Moléculaire (MEM), Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB) (BIAM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de biologie physico-chimique (IBPC (FR_550)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2000 |
| Předmět: |
Chlorophyll
MESH: Chlamydomonas reinhardtii MESH: Oxidation-Reduction Protein Conformation Heme MESH: Circular Dichroism Electron Transport Complex III MESH: Protein Conformation MESH: Electron Transport Complex III Animals MESH: Protein Binding MESH: Cytochrome b Group MESH: Animals MESH: Cytochromes MESH: Spectrophotometry [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry Molecular Biology/Structural Biology [q-bio.BM] Circular Dichroism MESH: Cytochrome b6f Complex Cytochrome b Group Cytochromes f [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry Molecular Biology/Biomolecules [q-bio.BM] Cytochrome b6f Complex Spectrophotometry MESH: Heme Liposomes MESH: Cytochromes f Cytochromes MESH: Liposomes Oxidation-Reduction MESH: Chlorophyll Chlamydomonas reinhardtii Protein Binding |
| Zdroj: | Journal of Biological Chemistry Journal of Biological Chemistry, American Society for Biochemistry and Molecular Biology, 2000, 275 (8), pp.5275-83 Journal of Biological Chemistry, 2000, 275 (8), pp.5275-83 |
| ISSN: | 0021-9258 1083-351X |
| Popis: | International audience; The organization of chromophores in the cytochrome b(6) f from Chlamydomonas reinhardtii has been studied spectroscopically. Linear dichroism (LD) measurements, performed on the complex co-reconstituted into vesicles with photosynthetic reaction centers as an internal standard, allow the determination of the orientations of the chromophore with respect to the membrane plane. The orientations of the b(H)- and b(L)-hemes are comparable to those determined crystallographically on the cytochrome bc(1). The excitonic CD signal, resulting from the interaction between b-hemes, is similar to that reported for the cytochrome bc(1). LD and CD data are consistent with the differences between the b(6) f and bc(1) leaving the orientation of the b-hemes unaffected. By contrast, the LD data yield a different orientation for the heme f as compared either to the heme c(1) in the crystallographic structures or to the heme f as studied by electron paramagnetic resonance. This difference could either result from incorrect assumptions regarding the orientations of the electronic transitions of the f-heme or may point to the possibility of a redox-dependent movement of cytochrome f. The chlorophyll a was observed in a well defined orientation, further corroborating a specific binding site for it in the b(6) f complex. |
| Databáze: | OpenAIRE |
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