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  1 / 2499 MEDLINE  
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[PMID]:28970007
[Au] Autor:Preissler J; Wahlefeld S; Lorent C; Teutloff C; Horch M; Lauterbach L; Cramer SP; Zebger I; Lenz O
[Ad] Endereço:Technische Universität Berlin, Institut für Chemie, Sekr. PC14, Straße des 17. Juni 135, D-10623 Berlin, Germany.
[Ti] Título:Enzymatic and spectroscopic properties of a thermostable [NiFe]­hydrogenase performing H -driven NAD -reduction in the presence of O .
[So] Source:Biochim Biophys Acta;1859(1):8-18, 2018 01.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Biocatalysts that mediate the H -dependent reduction of NAD to NADH are attractive from both a fundamental and applied perspective. Here we present the first biochemical and spectroscopic characterization of an NAD -reducing [NiFe]­hydrogenase that sustains catalytic activity at high temperatures and in the presence of O , which usually acts as an inhibitor. We isolated and sequenced the four structural genes, hoxFUYH, encoding the soluble NAD -reducing [NiFe]­hydrogenase (SH) from the thermophilic betaproteobacterium, Hydrogenophilus thermoluteolus TH-1 (Ht). The HtSH was recombinantly overproduced in a hydrogenase-free mutant of the well-studied, H -oxidizing betaproteobacterium Ralstonia eutropha H16 (Re). The enzyme was purified and characterized with various biochemical and spectroscopic techniques. Highest H -mediated NAD reduction activity was observed at 80°C and pH6.5, and catalytic activity was found to be sustained at low O concentrations. Infrared spectroscopic analyses revealed a spectral pattern for as-isolated HtSH that is remarkably different from those of the closely related ReSH and other [NiFe]­hydrogenases. This indicates an unusual configuration of the oxidized catalytic center in HtSH. Complementary electron paramagnetic resonance spectroscopic analyses revealed spectral signatures similar to related NAD -reducing [NiFe]­hydrogenases. This study lays the groundwork for structural and functional analyses of the HtSH as well as application of this enzyme for H -driven cofactor recycling under oxic conditions at elevated temperatures.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Cupriavidus necator/enzimologia
Temperatura Alta
Hidrogênio/química
Hidrogenase/química
Hydrogenophilaceae/enzimologia
NAD/química
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Cupriavidus necator/genética
Estabilidade Enzimática
Hidrogênio/metabolismo
Hidrogenase/genética
Hidrogenase/metabolismo
Hydrogenophilaceae/genética
NAD/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0U46U6E8UK (NAD); 7YNJ3PO35Z (Hydrogen); EC 1.12.- (nickel-iron hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171004
[St] Status:MEDLINE


  2 / 2499 MEDLINE  
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[PMID]:28919500
[Au] Autor:Mebs S; Kositzki R; Duan J; Kertess L; Senger M; Wittkamp F; Apfel UP; Happe T; Stripp ST; Winkler M; Haumann M
[Ad] Endereço:Department of Physics, Biophysics of Metalloenzymes, Freie Universität Berlin, 14195 Berlin, Germany.
[Ti] Título:Hydrogen and oxygen trapping at the H-cluster of [FeFe]-hydrogenase revealed by site-selective spectroscopy and QM/MM calculations.
[So] Source:Biochim Biophys Acta;1859(1):28-41, 2018 01.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:[FeFe]-hydrogenases are superior hydrogen conversion catalysts. They bind a cofactor (H-cluster) comprising a four-iron and a diiron unit with three carbon monoxide (CO) and two cyanide (CN ) ligands. Hydrogen (H ) and oxygen (O ) binding at the H-cluster was studied in the C169A variant of [FeFe]-hydrogenase HYDA1, in comparison to the active oxidized (Hox) and CO-inhibited (Hox-CO) species in wildtype enzyme. Fe labeling of the diiron site was achieved by in vitro maturation with a synthetic cofactor analogue. Site-selective X-ray absorption, emission, and nuclear inelastic/forward scattering methods and infrared spectroscopy were combined with quantum chemical calculations to determine the molecular and electronic structure and vibrational dynamics of detected cofactor species. Hox reveals an apical vacancy at Fe in a [4Fe4S-2Fe] complex with the net spin on Fe whereas Hox-CO shows an apical CN at Fe in a [4Fe4S-2Fe(CO)] complex with net spin sharing among Fe and Fe (proximal or distal iron ions in [2Fe]). At ambient O pressure, a novel H-cluster species (Hox-O ) accumulated in C169A, assigned to a [4Fe4S-2Fe(O )] complex with an apical superoxide (O ) carrying the net spin bound at Fe . H exposure populated the two-electron reduced Hhyd species in C169A, assigned as a [(H)4Fe4S-2Fe(H)] complex with the net spin on the reduced cubane, an apical hydride at Fe , and a proton at a cysteine ligand. Hox-O and Hhyd are stabilized by impaired O protonation or proton release after H cleavage due to interruption of the proton path towards and out of the active site.
[Mh] Termos MeSH primário: Chlamydomonas reinhardtii/enzimologia
Hidrogênio/química
Hidrogenase/química
Proteínas com Ferro-Enxofre/química
Oxigênio/química
Proteínas de Plantas/química
[Mh] Termos MeSH secundário: Domínio Catalítico
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Iron-Sulfur Proteins); 0 (Plant Proteins); 7YNJ3PO35Z (Hydrogen); EC 1.12.7.2 (Hydrogenase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170919
[St] Status:MEDLINE


  3 / 2499 MEDLINE  
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[PMID]:29193978
[Au] Autor:Balestri D; Roux Y; Mattarozzi M; Mucchino C; Heux L; Brazzolotto D; Artero V; Duboc C; Pelagatti P; Marchiò L; Gennari M
[Ad] Endereço:Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università degli Studi di Parma , Parco Area delle Scienze 17A, 43124 Parma, Italy.
[Ti] Título:Heterogenization of a [NiFe] Hydrogenase Mimic through Simple and Efficient Encapsulation into a Mesoporous MOF.
[So] Source:Inorg Chem;56(24):14801-14808, 2017 Dec 18.
[Is] ISSN:1520-510X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In the quest for new, efficient, and noble-metal-free H -evolution catalysts, hydrogenase enzymes are a source of inspiration. Here, we describe the development of a new hybrid material based on a structural and functional [NiFe]-hydrogenase model complex (NiFe) incorporated into the Zr-based MOF PCN-777. The bulk NiFe@PCN-777 material was synthesized by simple encapsulation. Characterization by solid-state NMR and IR spectroscopy, SEM-EDX, ICP-OES, and gas adsorption confirmed the inclusion of the guest. FTO-supported thin films of the NiFe@PCN-777 composite were obtained by electrophoretic deposition of the bulk material and characterized by SEM-EDX, ICP-OES, and cyclic voltammetry. The average surface concentration of electroactive NiFe catalyst in the film was found to be ∼9.6 × 10 mol cm , implying that a surprisingly high fraction (37%) of NiFe units incorporated in the MOF are electroactive. By cyclic voltammetry, we showed that NiFe maintains its electrocatalytic capabilities for H reduction inside the MOF cavities, even if under controlled-potential electrolysis conditions the activity of NiFe cannot be discerned from that of free PCN-777 and FTO.
[Mh] Termos MeSH primário: Materiais Biomiméticos/química
Hidrogenase/química
Ferro/química
Estruturas Metalorgânicas/química
Níquel/química
Zircônio/química
[Mh] Termos MeSH secundário: Catálise
Técnicas Eletroquímicas
Modelos Moleculares
Oxirredução
Prótons
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Metal-Organic Frameworks); 0 (Protons); 7OV03QG267 (Nickel); C6V6S92N3C (Zirconium); E1UOL152H7 (Iron); EC 1.12.- (nickel-iron hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171202
[St] Status:MEDLINE
[do] DOI:10.1021/acs.inorgchem.7b01824


  4 / 2499 MEDLINE  
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[PMID]:29188999
[Au] Autor:Song LC; Zhu L; Hu FQ; Wang YX
[Ad] Endereço:Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, and ‡Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University , Tianjin 300071, China.
[Ti] Título:Studies on Chemical Reactivity and Electrocatalysis of Two Acylmethyl(hydroxymethyl)pyridine Ligand-Containing [Fe]-Hydrogenase Models (2-COCH -6-HOCH C H N)Fe(CO) L (L = η -SCOMe, η -2-SC H N).
[So] Source:Inorg Chem;56(24):15216-15230, 2017 Dec 18.
[Is] ISSN:1520-510X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:On the basis of preparation and characterization of [Fe]-H ase models (2-COCH -6-HOCH C H N)Fe(CO) L (A, L = η -SCOMe; B, L = η -2-SC H N), the chemical reactivities of A and B with various electrophilic and nucleophilic reagents have been investigated, systematically. Thus, when A reacted with 1 equiv of MeCOCl in the presence of Et N in MeCN to give the η -SCOMe-coordinated acylation product (2-COCH -6-MeCO CH C H N)Fe(CO) (η -SCOMe) (1), treatment of A with excess HBF ·Et O in MeCN gave the cationic MeCN-coordinated complex [(2-COCH -6-HOCH C H N)Fe(CO) (MeCN)](BF ) (2). In addition, when 2 was treated with 1 equiv of 2,6-(p-4-MeC H ) C H SK or PPh in CH Cl to give the thiophenolato- and PPh -substituted derivatives (2-COCH -6-HOCH C H N)Fe(CO) [2,6-(p-MeC H ) C H S] (3) and [(2-COCH -6-HOCH C H N)Fe(CO) (PPh )](BF ) (4), treatment of B with 1 equiv of PMe or P(OMe) in THF afforded the phosphine- and phosphite-substituted complexes (2-COCH -6-HOCH C H N)(η -2-SC H N)Fe(CO) L (5, L = PMe ; 6, L = P(OMe) ). Interestingly, in contrast to A, when B reacted with excess HBF ·Et O in MeCN to afford the BF adduct [2-COCH -6-HO(BF )CH C H N]Fe(CO) (η -2-SC H N) (7), reaction of B with 1 equiv of p-MeC H COCl in the presence of Et N in MeCN gave not only the expected 2-acylmethyl-6-p-toluoyloxomethylpyridine-containing complex (2-COCH -6-p-MeC H CO CH C H N)Fe(CO) (η -2-SC H N) (8), but also gave the unexpected 2-toluoyloxovinyl-6-toluoyloxomethylpyridine-containing complex (2-p-MeC H CO C H-6-p-MeC H CO CH C H N)Fe(CO) (η -2-SC H N) (9). While the possible pathways for the novel reactions leading to complexes 1, 2, and 7-9 are suggested, the structures of complexes B, 1-4, and 6-9 were unambiguously confirmed by X-ray crystallography. In addition, model complexes A and B have been found to be catalysts for proton reduction to H from TFA under CV conditions.
[Mh] Termos MeSH primário: Materiais Biomiméticos/química
Hidrogenase/química
Compostos de Ferro/química
Proteínas com Ferro-Enxofre/química
Piridinas/química
[Mh] Termos MeSH secundário: Catálise
Cristalografia por Raios X
Técnicas Eletroquímicas
Ligantes
Modelos Moleculares
Oxirredução
Prótons
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Iron Compounds); 0 (Iron-Sulfur Proteins); 0 (Ligands); 0 (Protons); 0 (Pyridines); 0 (acylmethyl(hydroxymethyl)pyridine); EC 1.12.- (iron hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171201
[St] Status:MEDLINE
[do] DOI:10.1021/acs.inorgchem.7b02582


  5 / 2499 MEDLINE  
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[PMID]:29264600
[Au] Autor:Breglia R; Greco C; Fantucci P; De Gioia L; Bruschi M
[Ad] Endereço:Department of Earth and Environmental Science, University of Milano Bicocca, Piazza della Scienza 1, 20126 Milan, Italy. maurizio.bruschi@unimib.it.
[Ti] Título:Theoretical investigation of aerobic and anaerobic oxidative inactivation of the [NiFe]-hydrogenase active site.
[So] Source:Phys Chem Chem Phys;20(3):1693-1706, 2018 Jan 17.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The extraordinary capability of [NiFe]-hydrogenases to catalyse the reversible interconversion of protons and electrons into dihydrogen (H ) has stimulated numerous experimental and theoretical studies addressing the direct utilization of these enzymes in H production processes. Unfortunately, the introduction of these natural H -catalysts in biotechnological applications is limited by their inhibition under oxidising (aerobic and anaerobic) conditions. With the aim of contributing to overcome this limitation, we studied the oxidative inactivation mechanism of [NiFe]-hydrogenases by performing Density Functional Theory (DFT) calculations on a very large model of their active site in which all the amino acids forming the first and second coordination spheres of the NiFe cluster have been explicitly included. We identified an O molecule and two H O molecules as sources of the two oxygen atoms that are inserted at the active site of the inactive forms of the enzyme (Ni-A and Ni-B) under aerobic and anaerobic conditions, respectively. Furthermore, our results support the experimental evidence that the Ni-A-to-Ni-B ratio strongly depends on the number of reducing equivalents available for the process and on the oxidizing conditions under which the reaction takes place.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Hidrogenase/química
Modelos Moleculares
[Mh] Termos MeSH secundário: Proteínas de Bactérias/metabolismo
Biocatálise
Domínio Catalítico
Chromatiaceae/enzimologia
Hidrogênio/química
Hidrogenase/metabolismo
Oxirredução
Oxigênio/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 7YNJ3PO35Z (Hydrogen); EC 1.12.- (nickel-iron hydrogenase); EC 1.12.7.2 (Hydrogenase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171222
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06228a


  6 / 2499 MEDLINE  
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[PMID]:29205241
[Au] Autor:Dong G; Ryde U; Aa Jensen HJ; Hedegård ED
[Ad] Endereço:Department of Theoretical Chemistry, Lund University, Chemical Centre, P. O. Box 124, SE-221 00 Lund, Sweden. ulf.ryde@teokem.lu.se erik.hedegard@teokem.lu.se.
[Ti] Título:Exploration of H binding to the [NiFe]-hydrogenase active site with multiconfigurational density functional theory.
[So] Source:Phys Chem Chem Phys;20(2):794-801, 2018 Jan 03.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The combination of density functional theory (DFT) with a multiconfigurational wave function is an efficient way to include dynamical correlation in calculations with multiconfiguration self-consistent field wave functions. These methods can potentially be employed to elucidate reaction mechanisms in bio-inorganic chemistry, where many other methods become either too computationally expensive or too inaccurate. In this paper, a complete active space (CAS) short-range DFT (CAS-srDFT) hybrid was employed to investigate a bio-inorganic system, namely H binding to the active site of [NiFe] hydrogenase. This system was previously investigated with coupled-cluster (CC) and multiconfigurational methods in the form of cumulant-approximated second-order perturbation theory, based on the density matrix renormalization group (DMRG). We find that it is more favorable for H to bind to Ni than to Fe, in agreement with previous CC and DMRG calculations. The accuracy of CAS-srDFT is comparable to both CC and DMRG, despite much smaller active spaces were employed than in the corresponding DMRG calculations. This enhanced efficiency at the smaller active spaces shows that CAS-srDFT can become a useful method for bio-inorganic chemistry.
[Mh] Termos MeSH primário: Hidrogenase/química
Modelos Moleculares
[Mh] Termos MeSH secundário: Fenômenos Biofísicos
Domínio Catalítico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 1.12.- (nickel-iron hydrogenase); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180209
[Lr] Data última revisão:
180209
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171206
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06767d


  7 / 2499 MEDLINE  
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[PMID]:28809946
[Au] Autor:Blum FC; Hu HQ; Servetas SL; Benoit SL; Maier RJ; Maroney MJ; Merrell DS
[Ad] Endereço:Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America.
[Ti] Título:Structure-function analyses of metal-binding sites of HypA reveal residues important for hydrogenase maturation in Helicobacter pylori.
[So] Source:PLoS One;12(8):e0183260, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The nickel-containing enzymes of Helicobacter pylori, urease and hydrogenase, are essential for efficient colonization in the human stomach. The insertion of nickel into urease and hydrogenase is mediated by the accessory protein HypA. HypA contains an N-terminal nickel-binding site and a dynamic structural zinc-binding site. The coordination of nickel and zinc within HypA is known to be critical for urease maturation and activity. Herein, we test the hydrogenase activity of a panel of H. pylori mutant strains containing point mutations within the nickel- and zinc-binding sites. We found that the residues that are important for hydrogenase activity are those that were similarly vital for urease activity. Thus, the zinc and metal coordination sites of HypA play similar roles in urease and hydrogenase maturation. In other pathogenic bacteria, deletion of hydrogenase leads to a loss in acid resistance. Thus, the acid resistance of two strains of H. pylori containing a hydrogenase deletion was also tested. These mutant strains demonstrated wild-type levels of acid resistance, suggesting that in H. pylori, hydrogenase does not play a role in acid resistance.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
Helicobacter pylori/enzimologia
Hidrogenase/química
Hidrogenase/metabolismo
[Mh] Termos MeSH secundário: Sítios de Ligação
Helicobacter pylori/metabolismo
Concentração de Íons de Hidrogênio
Níquel/metabolismo
Ligação Proteica
Urease/química
Urease/metabolismo
Zinco/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 7OV03QG267 (Nickel); EC 1.12.7.2 (Hydrogenase); EC 3.5.1.5 (Urease); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171011
[Lr] Data última revisão:
171011
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170816
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0183260


  8 / 2499 MEDLINE  
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[PMID]:28774676
[Au] Autor:Khetkorn W; Rastogi RP; Incharoensakdi A; Lindblad P; Madamwar D; Pandey A; Larroche C
[Ad] Endereço:Division of Biology, Faculty of Science and Technology, Rajamangala University of Technology Thanyaburi, Thanyaburi, Pathumthani 12110, Thailand.
[Ti] Título:Microalgal hydrogen production - A review.
[So] Source:Bioresour Technol;243:1194-1206, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Bio-hydrogen from microalgae including cyanobacteria has attracted commercial awareness due to its potential as an alternative, reliable and renewable energy source. Photosynthetic hydrogen production from microalgae can be interesting and promising options for clean energy. Advances in hydrogen-fuel-cell technology may attest an eco-friendly way of biofuel production, since, the use of H to generate electricity releases only water as a by-product. Progress in genetic/metabolic engineering may significantly enhance the photobiological hydrogen production from microalgae. Manipulation of competing metabolic pathways by modulating the certain key enzymes such as hydrogenase and nitrogenase may enhance the evolution of H from photoautotrophic cells. Moreover, biological H production at low operating costs is requisite for economic viability. Several photobioreactors have been developed for large-scale biomass and hydrogen production. This review highlights the recent technological progress, enzymes involved and genetic as well as metabolic engineering approaches towards sustainable hydrogen production from microalgae.
[Mh] Termos MeSH primário: Hidrogenase
Microalgas
Fotobiorreatores
[Mh] Termos MeSH secundário: Biocombustíveis
Hidrogênio
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Biofuels); 7YNJ3PO35Z (Hydrogen); EC 1.12.7.2 (Hydrogenase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE


  9 / 2499 MEDLINE  
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[PMID]:28718449
[Au] Autor:Lindenstrauß U; Skorupa P; McDowall JS; Sargent F; Pinske C
[Ad] Endereço:Martin-Luther University Halle-Wittenberg, Institute of Biology/Microbiology, Kurt-Mothes-Str. 3, 06120 Halle, Germany.
[Ti] Título:The dual-function chaperone HycH improves assembly of the formate hydrogenlyase complex.
[So] Source:Biochem J;474(17):2937-2950, 2017 Aug 11.
[Is] ISSN:1470-8728
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The assembly of multi-protein complexes requires the concerted synthesis and maturation of its components and subsequently their co-ordinated interaction. The membrane-bound formate hydrogenlyase (FHL) complex is the primary hydrogen-producing enzyme in and is composed of seven subunits mostly encoded within the operon for [NiFe]-hydrogenase-3 (Hyd-3). The HycH protein is predicted to have an accessory function and is not part of the final structural FHL complex. In this work, a mutant strain devoid of HycH was characterised and found to have significantly reduced FHL activity due to the instability of the electron transfer subunits. HycH was shown to interact specifically with the unprocessed species of HycE, the catalytic hydrogenase subunit of the FHL complex, at different stages during the maturation and assembly of the complex. Variants of HycH were generated with the aim of identifying interacting residues and those that influence activity. The R70/71/K72, the Y79, the E81 and the Y128 variant exchanges interrupt the interaction with HycE without influencing the FHL activity. In contrast, FHL activity, but not the interaction with HycE, was negatively influenced by H37 exchanges with polar residues. Finally, a HycH Y30 variant was unstable. Surprisingly, an overlapping function between HycH with its homologous counterpart HyfJ from the operon encoding [NiFe]-hydrogenase-4 (Hyd-4) was identified and this is the first example of sharing maturation machinery components between Hyd-3 and Hyd-4 complexes. The data presented here show that HycH has a novel dual role as an assembly chaperone for a cytoplasmic [NiFe]-hydrogenase.
[Mh] Termos MeSH primário: Proteínas de Escherichia coli/metabolismo
Escherichia coli/metabolismo
Formiato Desidrogenases/genética
Hidrogenase/genética
Chaperonas Moleculares/metabolismo
Complexos Multienzimáticos/genética
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Estabilidade Enzimática/genética
Escherichia coli/genética
Proteínas de Escherichia coli/genética
Formiato Desidrogenases/metabolismo
Hidrogenase/metabolismo
Chaperonas Moleculares/genética
Complexos Multienzimáticos/metabolismo
Mutação de Sentido Incorreto
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (Molecular Chaperones); 0 (Multienzyme Complexes); EC 1.12.7.2 (Hydrogenase); EC 1.2.1.2 (Formate Dehydrogenases); EC 1.2.1.2 (formate hydrogenlyase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170719
[St] Status:MEDLINE
[do] DOI:10.1042/BCJ20170431


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[PMID]:28647463
[Au] Autor:Engelbrecht V; Rodríguez-Maciá P; Esselborn J; Sawyer A; Hemschemeier A; Rüdiger O; Lubitz W; Winkler M; Happe T
[Ad] Endereço:AG Photobiotechnologie, Fakultät für Biologie und Biotechnologie, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany.
[Ti] Título:The structurally unique photosynthetic Chlorella variabilis NC64A hydrogenase does not interact with plant-type ferredoxins.
[So] Source:Biochim Biophys Acta;1858(9):771-778, 2017 09.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Hydrogenases from green algae are linked to the photosynthetic electron transfer chain via the plant-type ferredoxin PetF. In this work the [FeFe]-hydrogenase from the Trebouxiophycean alga Chlorella variabilis NC64A (CvHydA1), which in contrast to other green algal hydrogenases contains additional FeS-cluster binding domains, was purified and specific enzyme activities for both hydrogen (H ) production and H oxidation were determined. Interestingly, although C. variabilis NC64A, like many Chlorophycean algal strains, exhibited light-dependent H production activity upon sulfur deprivation, CvHydA1 did not interact in vitro with several plant-type [2Fe-2S]-ferredoxins, but only with a bacterial2[4Fe4S]-ferredoxin. In an electrochemical characterization, the enzyme exhibited features typical of bacterial [FeFe]-hydrogenases (e.g. minor anaerobic oxidative inactivation), as well as of algal enzymes (very high oxygen sensitivity).
[Mh] Termos MeSH primário: Proteínas de Algas/metabolismo
Chlorella/enzimologia
Ferredoxinas/metabolismo
Hidrogenase/metabolismo
Proteínas com Ferro-Enxofre/metabolismo
Proteínas de Plantas/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Algas/química
Proteínas de Algas/isolamento & purificação
Sequência de Aminoácidos
Monóxido de Carbono/farmacologia
Chlamydomonas reinhardtii/química
Chlorella/efeitos da radiação
Técnicas Eletroquímicas
Transporte de Elétrons
Hidrogênio/metabolismo
Hidrogenase/antagonistas & inibidores
Hidrogenase/química
Hidrogenase/isolamento & purificação
Proteínas com Ferro-Enxofre/antagonistas & inibidores
Proteínas com Ferro-Enxofre/química
Proteínas com Ferro-Enxofre/isolamento & purificação
Luz
Modelos Moleculares
Oxirredução
Oxigênio/farmacologia
Fotossíntese
Conformação Proteica
Proteínas Recombinantes/metabolismo
Alinhamento de Sequência
Homologia de Sequência de Aminoácidos
Enxofre/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Algal Proteins); 0 (Ferredoxins); 0 (Iron-Sulfur Proteins); 0 (Plant Proteins); 0 (Recombinant Proteins); 70FD1KFU70 (Sulfur); 7U1EE4V452 (Carbon Monoxide); 7YNJ3PO35Z (Hydrogen); EC 1.12.- (iron hydrogenase); EC 1.12.7.2 (Hydrogenase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171025
[Lr] Data última revisão:
171025
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170626
[St] Status:MEDLINE



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