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[PMID]:24845964
[Au] Autor:Pietras R; Sarewicz M; Osyczka A
[Ad] Endereço:Department of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University , 30-387 Kraków, Poland.
[Ti] Título:Molecular organization of cytochrome c2 near the binding domain of cytochrome bc1 studied by electron spin-lattice relaxation enhancement.
[So] Source:J Phys Chem B;118(24):6634-43, 2014 Jun 19.
[Is] ISSN:1520-5207
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Measurements of specific interactions between proteins are challenging. In redox systems, interactions involve surfaces near the attachment sites of cofactors engaged in interprotein electron transfer (ET). Here we analyzed binding of cytochrome c2 to cytochrome bc1 by measuring paramagnetic relaxation enhancement (PRE) of spin label (SL) attached to cytochrome c2. PRE was exclusively induced by the iron atom of heme c1 of cytochrome bc1, which guaranteed that only the configurations with SL to heme c1 distances up to ∼30 Šwere detected. Changes in PRE were used to qualitatively and quantitatively characterize the binding. Our data suggest that at low ionic strength and under an excess of cytochrome c2 over cytochrome bc1, several cytochrome c2 molecules gather near the binding domain forming a "cloud" of molecules. When the cytochrome bc1 concentration increases, the cloud disperses to populate additional available binding domains. An increase in ionic strength weakens the attractive forces and the average distance between cytochrome c2 and cytochrome bc1 increases. The spatial arrangement of the protein complex at various ionic strengths is different. Above 150 mM NaCl the lifetime of the complexes becomes so short that they are undetectable. All together the results indicate that cytochrome c2 molecules, over the range of salt concentration encompassing physiological ionic strength, do not form stable, long-lived complexes but rather constantly collide with the surface of cytochrome bc1 and ET takes place coincidentally with one of these collisions.
[Mh] Termos MeSH primário: Citocromos c2/química
Complexo III da Cadeia de Transporte de Elétrons/química
[Mh] Termos MeSH secundário: Citocromos c2/metabolismo
Espectroscopia de Ressonância de Spin Eletrônica
Transporte de Elétrons
Complexo III da Cadeia de Transporte de Elétrons/metabolismo
Elétrons
Cinética
Concentração Osmolar
Ligação Proteica
Estrutura Terciária de Proteína
Rhodobacter capsulatus/metabolismo
Marcadores de Spin
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Spin Labels); 9035-43-2 (Cytochromes c2); EC 1.10.2.2 (Electron Transport Complex III)
[Em] Mês de entrada:1505
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140522
[St] Status:MEDLINE
[do] DOI:10.1021/jp503339g


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[PMID]:24317397
[Au] Autor:Bird LJ; Saraiva IH; Park S; Calçada EO; Salgueiro CA; Nitschke W; Louro RO; Newman DK
[Ad] Endereço:Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
[Ti] Título:Nonredundant roles for cytochrome c2 and two high-potential iron-sulfur proteins in the photoferrotroph Rhodopseudomonas palustris TIE-1.
[So] Source:J Bacteriol;196(4):850-8, 2014 Feb.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The purple bacterium Rhodopseudomonas palustris TIE-1 expresses multiple small high-potential redox proteins during photoautotrophic growth, including two high-potential iron-sulfur proteins (HiPIPs) (PioC and Rpal_4085) and a cytochrome c2. We evaluated the role of these proteins in TIE-1 through genetic, physiological, and biochemical analyses. Deleting the gene encoding cytochrome c2 resulted in a loss of photosynthetic ability by TIE-1, indicating that this protein cannot be replaced by either HiPIP in cyclic electron flow. PioC was previously implicated in photoferrotrophy, an unusual form of photosynthesis in which reducing power is provided through ferrous iron oxidation. Using cyclic voltammetry (CV), electron paramagnetic resonance (EPR) spectroscopy, and flash-induced spectrometry, we show that PioC has a midpoint potential of 450 mV, contains all the typical features of a HiPIP, and can reduce the reaction centers of membrane suspensions in a light-dependent manner at a much lower rate than cytochrome c2. These data support the hypothesis that PioC linearly transfers electrons from iron, while cytochrome c2 is required for cyclic electron flow. Rpal_4085, despite having spectroscopic characteristics and a reduction potential similar to those of PioC, is unable to reduce the reaction center. Rpal_4085 is upregulated by the divalent metals Fe(II), Ni(II), and Co(II), suggesting that it might play a role in sensing or oxidizing metals in the periplasm. Taken together, our results suggest that these three small electron transfer proteins perform different functions in the cell.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Citocromos c2/metabolismo
Proteínas com Ferro-Enxofre/metabolismo
Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo
Rodopseudomonas/enzimologia
Rodopseudomonas/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Citocromos c2/genética
Deleção de Genes
Proteínas com Ferro-Enxofre/genética
Luz
Metais/metabolismo
Oxirredução
Fotossíntese
Complexo de Proteínas do Centro de Reação Fotossintética/genética
Rodopseudomonas/genética
Análise Espectral
Eletricidade Estática
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Iron-Sulfur Proteins); 0 (Metals); 0 (Photosynthetic Reaction Center Complex Proteins); 0 (high potential iron-sulfur protein); 9035-43-2 (Cytochromes c2)
[Em] Mês de entrada:1403
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:131210
[St] Status:MEDLINE
[do] DOI:10.1128/JB.00843-13


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[PMID]:23539360
[Au] Autor:Vasilev C; Brindley AA; Olsen JD; Saer RG; Beatty JT; Hunter CN
[Ad] Endereço:Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK, c.vasilev@sheffield.ac.uk.
[Ti] Título:Nano-mechanical mapping of the interactions between surface-bound RC-LH1-PufX core complexes and cytochrome c 2 attached to an AFM probe.
[So] Source:Photosynth Res;120(1-2):169-80, 2014 May.
[Is] ISSN:1573-5079
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Electron transfer pathways in photosynthesis involve interactions between membrane-bound complexes such as reaction centres with an extrinsic partner. In this study, the biological specificity of electron transfer between the reaction centre-light-harvesting 1-PufX complex and its extrinsic electron donor, cytochrome c 2, formed the basis for mapping the location of surface-attached RC-LH1-PufX complexes using atomic force microscopy (AFM). This nano-mechanical mapping method used an AFM probe functionalised with cyt c 2 molecules to quantify the interaction forces involved, at the single-molecule level under native conditions. With surface-bound RC-His12-LH1-PufX complexes in the photo-oxidised state, the mean interaction force with cyt c 2 is approximately 480 pN with an interaction frequency of around 66 %. The latter value lowered 5.5-fold when chemically reduced RC-His12-LH1-PufX complexes are imaged in the dark to abolish electron transfer from cyt c 2 to the RC. The correspondence between topographic and adhesion images recorded over the same area of the sample shows that affinity-based AFM methods are a useful tool when topology alone is insufficient for spatially locating proteins at the surface of photosynthetic membranes.
[Mh] Termos MeSH primário: Citocromos c2/metabolismo
Microscopia de Força Atômica
Fotossíntese/fisiologia
[Mh] Termos MeSH secundário: Transporte de Elétrons/fisiologia
Modelos Biológicos
Rhodobacter sphaeroides/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
9035-43-2 (Cytochromes c2)
[Em] Mês de entrada:1411
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130330
[St] Status:MEDLINE
[do] DOI:10.1007/s11120-013-9812-7


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[PMID]:23543713
[Au] Autor:Hopper AC; Li Y; Cole JA
[Ad] Endereço:School of Biosciences, University of Birmingham, Birmingham, United Kingdom.
[Ti] Título:A critical role for the cccA gene product, cytochrome c2, in diverting electrons from aerobic respiration to denitrification in Neisseria gonorrhoeae.
[So] Source:J Bacteriol;195(11):2518-29, 2013 Jun.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Neisseria gonorrhoeae is a microaerophile that, when oxygen availability is limited, supplements aerobic respiration with a truncated denitrification pathway, nitrite reduction to nitrous oxide. We demonstrate that the cccA gene of Neisseria gonorrhoeae strain F62 (accession number NG0292) is expressed, but the product, cytochrome c2, accumulates to only low levels. Nevertheless, a cccA mutant reduced nitrite at about half the rate of the parent strain. We previously reported that cytochromes c4 and c5 transfer electrons to cytochrome oxidase cbb3 by two independent pathways and that the CcoP subunit of cytochrome oxidase cbb3 transfers electrons to nitrite. We show that mutants defective in either cytochrome c4 or c5 also reduce nitrite more slowly than the parent. By combining mutations in cccA (Δc2), cycA (Δc4), cycB (Δc5), and ccoP (ccoP-C368A), we demonstrate that cytochrome c2 is required for electron transfer from cytochrome c4 via the third heme group of CcoP to the nitrite reductase, AniA, and that cytochrome c5 transfers electrons to nitrite reductase by an independent pathway. We propose that cytochrome c2 forms a complex with cytochrome oxidase. If so, the redox state of cytochrome c2 might regulate electron transfer to nitrite or oxygen. However, our data are more consistent with a mechanism in which cytochrome c2 and the CcoQ subunit of cytochrome oxidase form alternative complexes that preferentially catalyze nitrite and oxygen reduction, respectively. Comparison with the much simpler electron transfer pathway for nitrite reduction in the meningococcus provides fascinating insights into niche adaptation within the pathogenic neisseriae.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Citocromos c2/metabolismo
Regulação Bacteriana da Expressão Gênica
Neisseria gonorrhoeae/metabolismo
Nitritos/metabolismo
Oxigênio/metabolismo
[Mh] Termos MeSH secundário: Adaptação Fisiológica
Antígenos de Bactérias
Proteínas da Membrana Bacteriana Externa
Proteínas de Bactérias/genética
Biologia Computacional
Grupo dos Citocromos c/genética
Grupo dos Citocromos c/metabolismo
Citocromos c2/genética
Desnitrificação
Transporte de Elétrons
Teste de Complementação Genética
Heme/metabolismo
Neisseria gonorrhoeae/genética
Neisseria gonorrhoeae/fisiologia
Oxirredução
Estrutura Terciária de Proteína
Proteínas Recombinantes de Fusão
Reprodutibilidade dos Testes
Deleção de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Antigens, Bacterial); 0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (Cytochrome c Group); 0 (Nitrites); 0 (Recombinant Fusion Proteins); 0 (aniA protein, Neisseria gonorrhoeae); 39405-42-0 (cytochrome C4); 42VZT0U6YR (Heme); 51811-53-1 (cytochrome C5); 9035-43-2 (Cytochromes c2); S88TT14065 (Oxygen)
[Em] Mês de entrada:1307
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130402
[St] Status:MEDLINE
[do] DOI:10.1128/JB.02300-12


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[PMID]:23050746
[Au] Autor:Chen W; Djama ZR; Coffey MD; Martin FN; Bilodeau GJ; Radmer L; Denton G; Lévesque CA
[Ad] Endereço:Agriculture & Agri-Food Canada, Central Experimental Farm, Ottawa, Ontario K1A 0C6, Canada.
[Ti] Título:Membrane-based oligonucleotide array developed from multiple markers for the detection of many Phytophthora species.
[So] Source:Phytopathology;103(1):43-54, 2013 Jan.
[Is] ISSN:0031-949X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Most Phytophthora spp. are destructive plant pathogens; therefore, effective monitoring and accurate early detection are important means of preventing potential epidemics and outbreaks of diseases. In the current study, a membrane-based oligonucleotide array was developed that can detect Phytophthora spp. reliably using three DNA regions; namely, the internal transcribed spacer (ITS), the 5' end of cytochrome c oxidase 1 gene (cox1), and the intergenic region between cytochrome c oxidase 2 gene (cox2) and cox1 (cox2-1 spacer). Each sequence data set contained ≈250 sequences representing 98 described and 15 undescribed species of Phytophthora. The array was validated with 143 pure cultures and 35 field samples. Together, nonrejected oligonucleotides from all three markers have the ability to reliably detect 82 described and 8 undescribed Phytophthora spp., including several quarantine or regulated pathogens such as Phytophthora ramorum. Our results showed that a DNA array containing signature oligonucleotides designed from multiple genomic regions provided robustness and redundancy for the detection and differentiation of closely related taxon groups. This array has the potential to be used as a routine diagnostic tool for Phytophthora spp. from complex environmental samples without the need for extensive growth of cultures.
[Mh] Termos MeSH primário: Marcadores Genéticos/genética
Análise de Sequência com Séries de Oligonucleotídeos/métodos
Phytophthora/isolamento & purificação
Doenças das Plantas/parasitologia
Plantas/parasitologia
[Mh] Termos MeSH secundário: Análise por Conglomerados
Citocromos c1/genética
Citocromos c2/genética
DNA Intergênico/genética
DNA Espaçador Ribossômico/genética
Estudos de Viabilidade
Oligonucleotídeos/genética
Filogenia
Phytophthora/classificação
Phytophthora/genética
Folhas de Planta/parasitologia
Raízes de Plantas/parasitologia
Caules de Planta/parasitologia
Reação em Cadeia da Polimerase
Pythium/classificação
Pythium/genética
Pythium/isolamento & purificação
Solo
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (DNA, Intergenic); 0 (DNA, Ribosomal Spacer); 0 (Genetic Markers); 0 (Oligonucleotides); 0 (Soil); 9035-42-1 (Cytochromes c1); 9035-43-2 (Cytochromes c2)
[Em] Mês de entrada:1406
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:121012
[St] Status:MEDLINE
[do] DOI:10.1094/PHYTO-04-12-0092-R


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[PMID]:22306765
[Au] Autor:Kyndt JA; Fitch JC; Berry RE; Stewart MC; Whitley K; Meyer TE; Walker FA; Cusanovich MA
[Ad] Endereço:Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA. jkyndt@email.arizona.edu
[Ti] Título:Tyrosine triad at the interface between the Rieske iron-sulfur protein, cytochrome c1 and cytochrome c2 in the bc1 complex of Rhodobacter capsulatus.
[So] Source:Biochim Biophys Acta;1817(5):811-8, 2012 May.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A triad of tyrosine residues (Y152-154) in the cytochrome c(1) subunit (C1) of the Rhodobacter capsulatus cytochrome bc(1) complex (BC1) is ideally positioned to interact with cytochrome c(2) (C2). Mutational analysis of these three tyrosines showed that, of the three, Y154 is the most important, since its mutation to alanine resulted in significantly reduced levels, destabilization, and inactivation of BC1. A second-site revertant of this mutant that regained photosynthetic capacity was found to have acquired two further mutations-A181T and A200V. The Y152Q mutation did not change the spectral or electrochemical properties of C1, and showed wild-type enzymatic C2 reduction rates, indicating that this mutation did not introduce major structural changes in C1 nor affect overall activity. Mutations Y153Q and Y153A, on the other hand, clearly affect the redox properties of C1 (e.g. by lowering the midpoint potential as much as 117 mV in Y153Q) and the activity by 90% and 50%, respectively. A more conservative Y153F mutant on the other hand, behaves similarly to wild-type. This underscores the importance of an aromatic residue at position Y153, presumably to maintain close packing with P184, which modeling indicates is likely to stabilize the sixth heme ligand conformation.
[Mh] Termos MeSH primário: Citocromos c1/metabolismo
Citocromos c2/metabolismo
Complexo III da Cadeia de Transporte de Elétrons/metabolismo
Rhodobacter capsulatus/metabolismo
Tirosina/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Biocatálise
Citocromos c1/química
Citocromos c2/química
Complexo III da Cadeia de Transporte de Elétrons/química
Eletroforese em Gel de Poliacrilamida
Heme/química
Modelos Moleculares
Dados de Sequência Molecular
Mutação/genética
Rhodobacter capsulatus/crescimento & desenvolvimento
Alinhamento de Sequência
Análise Espectral
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Rieske iron-sulfur protein); 42HK56048U (Tyrosine); 42VZT0U6YR (Heme); 9035-42-1 (Cytochromes c1); 9035-43-2 (Cytochromes c2); EC 1.10.2.2 (Electron Transport Complex III)
[Em] Mês de entrada:1304
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120207
[St] Status:MEDLINE
[do] DOI:10.1016/j.bbabio.2012.01.013


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[PMID]:21956106
[Au] Autor:Verissimo AF; Yang H; Wu X; Sanders C; Daldal F
[Ad] Endereço:Department of Biology, University of Pennsylvania Philadelphia, Pennsylvania 19014-6019, USA.
[Ti] Título:CcmI subunit of CcmFHI heme ligation complex functions as an apocytochrome c chaperone during c-type cytochrome maturation.
[So] Source:J Biol Chem;286(47):40452-63, 2011 Nov 25.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cytochrome c maturation (Ccm) is a sophisticated post-translational process. It occurs after translocation of apocytochromes c to the p side of energy transducing membranes and forms stereo-specific thioether bonds between the vinyl groups of heme b (protoporphyrin IX-Fe) and the thiol groups of cysteines at their conserved heme binding sites. In many organisms this process involves up to 10 (CcmABCDEFGHI and CcdA) membrane proteins. One of these proteins is CcmI, which has an N-terminal membrane-embedded domain with two transmembrane helices and a large C-terminal periplasmic domain with protein-protein interaction motifs. Together with CcmF and CcmH, CcmI forms a multisubunit heme ligation complex. How the CcmFHI complex recognizes its apocytochrome c substrates remained unknown. In this study, using Rhodobacter capsulatus apocytochrome c(2) as a Ccm substrate, we demonstrate for the first time that CcmI binds apocytochrome c(2) but not holocytochrome c(2). Mainly the C-terminal portions of both CcmI and apocytochrome c(2) mediate this binding. Other physical interactions via the conserved structural elements in apocytochrome c(2), like the heme ligating cysteines or heme iron axial ligands, are less crucial. Furthermore, we show that the N-terminal domain of CcmI can also weakly bind apocytochrome c(2), but this interaction requires a free thiol group at apocytochrome c(2) heme binding site. We conclude that the CcmI subunit of the CcmFHI complex functions as an apocytochrome c chaperone during the Ccm process used by proteobacteria, archaea, mitochondria of plants and red algae.
[Mh] Termos MeSH primário: Citocromos c/química
Citocromos c/metabolismo
Heme/metabolismo
Chaperonas Moleculares/metabolismo
Processamento de Proteína Pós-Traducional
Subunidades Proteicas/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Sítios de Ligação
Membrana Celular/metabolismo
Citocromos c2/metabolismo
Epitopos/metabolismo
Modelos Moleculares
Chaperonas Moleculares/biossíntese
Chaperonas Moleculares/química
Chaperonas Moleculares/isolamento & purificação
Dados de Sequência Molecular
Fragmentos de Peptídeos/química
Fragmentos de Peptídeos/metabolismo
Periplasma/enzimologia
Ligação Proteica
Estrutura Secundária de Proteína
Subunidades Proteicas/biossíntese
Subunidades Proteicas/química
Subunidades Proteicas/isolamento & purificação
Rhodobacter capsulatus/citologia
Rhodobacter capsulatus/enzimologia
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Epitopes); 0 (Molecular Chaperones); 0 (Peptide Fragments); 0 (Protein Subunits); 42VZT0U6YR (Heme); 9007-43-6 (Cytochromes c); 9035-43-2 (Cytochromes c2)
[Em] Mês de entrada:1201
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110930
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M111.277764


  8 / 187 MEDLINE  
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[PMID]:21789203
[Au] Autor:Harbitz E; Andersson KK
[Ad] Endereço:Department of Molecular Biosciences, University of Oslo, Oslo, Norway.
[Ti] Título:Cytochrome c-554 from Methylosinus trichosporium OB3b; a protein that belongs to the cytochrome c2 family and exhibits a HALS-Type EPR signal.
[So] Source:PLoS One;6(7):e22014, 2011.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A small soluble cytochrome c-554 purified from Methylosinus trichosporium OB3b has been purified and analyzed by amino acid sequencing, mass spectrometry, visible, CD and EPR spectroscopies. It is found to be a mono heme protein with a characteristic cytochrome c fold, thus fitting into the class of cytochrome c(2), which is the bacterial homologue of mitochondrial cytochrome c. The heme iron has a Histidine/Methionine axial ligation and exhibits a highly anisotropic/axial low spin (HALS) EPR signal, with a g(max) at 3.40, and ligand field parameters V/ξ = 0.99, Δ/ξ = 4.57. This gives the rhombicity V/Δ = 0.22. The structural basis for this HALS EPR signal in Histidine/Methionine ligated hemes is not resolved. The ligand field parameters observed for cytochrome c-554 fits the observed pattern for other cytochromes with similar ligation and EPR behaviour.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Grupo dos Citocromos c/metabolismo
Citocromos c2/metabolismo
Methylosinus trichosporium/metabolismo
Marcadores de Spin
[Mh] Termos MeSH secundário: Absorção
Sequência de Aminoácidos
Animais
Anisotropia
Proteínas de Bactérias/química
Proteínas de Bactérias/isolamento & purificação
Dicroísmo Circular
Grupo dos Citocromos b/metabolismo
Grupo dos Citocromos c/química
Grupo dos Citocromos c/isolamento & purificação
Espectroscopia de Ressonância de Spin Eletrônica
Heme/metabolismo
Cavalos
Espectrometria de Massas
Metionina/metabolismo
Methylococcus capsulatus/metabolismo
Dados de Sequência Molecular
Peso Molecular
Homologia Estrutural de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cytochrome b Group); 0 (Cytochrome c Group); 0 (Spin Labels); 42VZT0U6YR (Heme); 61132-16-9 (cytochrome b 555); 9035-43-2 (Cytochromes c2); 9048-78-6 (cytochrome C-552); AE28F7PNPL (Methionine)
[Em] Mês de entrada:1111
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110727
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0022014


  9 / 187 MEDLINE  
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[PMID]:21431229
[Au] Autor:Sarewicz M; Pietras R; Froncisz W; Osyczka A
[Ad] Endereço:Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, ul Gronostajowa 7, 30-307 Kraków, Poland.
[Ti] Título:Reorientation of cytochrome c2 upon interaction with oppositely charged macromolecules probed by SR EPR: implications for the role of dipole moment to facilitate collisions in proper configuration for electron transfer.
[So] Source:Metallomics;3(4):404-9, 2011 Apr.
[Is] ISSN:1756-591X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The reaction of water-soluble cytochrome c (c(2)) with its physiological redox partners is facilitated by electrostatic attractions between the two protein surfaces. Using spin-labeled cytochrome c(2) from Rhodobacter capsulatus and pulse electron paramagnetic resonance (EPR) measurements we compared spatial orientation of cytochrome c(2) upon its binding to surfaces of opposite charge. We observed that cytochrome c(2) can use its negatively charged "back" side when exposed to interact with positively charged surfaces (DEAE resin) which is the opposite to the use of its positively charged "front" side in physiological interaction with negatively charged binding domain of cytochrome bc(1). The later orientation is also adopted upon non-physiological binding of cytochrome c(2) to negatively charged carboxymethyl cellulose resin. These results directly demonstrate how the electric dipolar nature of cytochrome c(2) influences its orientation in interactions with charged surfaces, which may facilitate collisions with other redox proteins in a proper orientation to support physiologically-competent electron transfer. Saturation recovery EPR provides an attractive tool for monitoring spatial orientation of proteins in their interaction with surfaces in liquid phase. It is particularly valuable for metalloproteins engaged in redox reactions as a means to monitor the geometry and dynamics of formation of protein complexes in measurements that are independent of electron transfer processes.
[Mh] Termos MeSH primário: Citocromos c2/metabolismo
Espectroscopia de Ressonância de Spin Eletrônica/métodos
Rhodobacter capsulatus/enzimologia
[Mh] Termos MeSH secundário: Transporte de Elétrons
Modelos Moleculares
Ligação Proteica
Eletricidade Estática
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
9035-43-2 (Cytochromes c2)
[Em] Mês de entrada:1107
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110325
[St] Status:MEDLINE
[do] DOI:10.1039/c0mt00105h


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[PMID]:20697695
[Au] Autor:Meyer T; Van Driessche G; Ambler R; Kyndt J; Devreese B; Van Beeumen J; Cusanovich M
[Ad] Endereço:Department of Chemistry and Biochemistry, University of Arizona, Tucson, 85721, USA. temeyer@u.arizona.edu
[Ti] Título:Evidence from the structure and function of cytochromes c(2) that nonsulfur purple bacterial photosynthesis followed the evolution of oxygen respiration.
[So] Source:Arch Microbiol;192(10):855-65, 2010 Oct.
[Is] ISSN:1432-072X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Cytochromes c(2) are the nearest bacterial homologs of mitochondrial cytochrome c. The sequences of the known cytochromes c(2) can be placed in two subfamilies based upon insertions and deletions, one subfamily is most like mitochondrial cytochrome c (the small C2s, without significant insertions and deletions), and the other, designated large C2, shares 3- and 8-residue insertions as well as a single-residue deletion. C2s generally function between cytochrome bc(1) and cytochrome oxidase in respiration (ca 80 examples known to date) and between cytochrome bc(1) and the reaction center in nonsulfur purple bacterial photosynthesis (ca 21 examples). However, members of the large C2 subfamily are almost always involved in photosynthesis (12 of 14 examples). In addition, the gene for the large C2 (cycA) is associated with those for the photosynthetic reaction center (pufBALM). We hypothesize that the insertions in the large C2s, which were already functioning in photosynthesis, allowed them to replace the membrane-bound tetraheme cytochrome, PufC, that otherwise mediates between the small C2 or other redox proteins and photosynthetic reaction centers. Based upon our analysis, we propose that the involvement of C2 in nonsulfur purple bacterial photosynthesis was a metabolic feature subsequent to the evolution of oxygen respiration.
[Mh] Termos MeSH primário: Citocromos c2/química
Oxigênio/metabolismo
Fotossíntese
Complexo de Proteínas do Centro de Reação Fotossintética/genética
Rhodospirillaceae/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Citocromos c2/classificação
Evolução Molecular
Modelos Moleculares
Dados de Sequência Molecular
Oxirredução
Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo
Rhodospirillaceae/genética
Alinhamento de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Photosynthetic Reaction Center Complex Proteins); 9035-43-2 (Cytochromes c2); S88TT14065 (Oxygen)
[Em] Mês de entrada:1011
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100811
[St] Status:MEDLINE
[do] DOI:10.1007/s00203-010-0608-2



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