Synthesis of the H-cluster framework of iron-only hydrogenase

  title={Synthesis of the H-cluster framework of iron-only hydrogenase},
  author={C{\'e}dric Tard and Xiaoming Liu and Saad K. Ibrahim and Maurizio Bruschi and Luca De Gioia and S{\^i}an C. Davies and Xin Yang and Lai‐Sheng Wang and Gary Sawers and Christopher J. Pickett},
The metal-sulphur active sites of hydrogenases catalyse hydrogen evolution or uptake at rapid rates. Understanding the structure and function of these active sites—through mechanistic studies of hydrogenases, synthetic assemblies and in silico models—will help guide the design of new materials for hydrogen production or uptake. Here we report the assembly of the iron-sulphur framework of the active site of iron-only hydrogenase (the H-cluster), and show that it functions as an electrocatalyst… 

The modular assembly of clusters is the natural synthetic strategy for the active site of [FeFe] hydrogenase.

A structural report from Mulder, Peters, Broderick et al. on the nature of the 2Fe2S subsite precursor, which highlights the need for an optimal synthetic analogue of the active site, without protein, as prospective molecular electrocatalysts for hydrogen production.

Reactions of [FeFe]-hydrogenase models involving the formation of hydrides related to proton reduction and hydrogen oxidation.

The differences in structure and catalytic mechanism between the synthetic models and the native [ FeFe]-H2ase active site are compared and analyzed, which may cause the need for a significantly larger driving force and may lead to lower activities of synthetic models than the [FeFe]- H2ases for H2 generation and uptake.

Reactivation of the Ready and Unready Oxidized States of [NiFe]-Hydrogenases: Mechanistic Insights from DFT Calculations.

In this work, reactivation mechanism of the oxidized and inactive Ni-B and Ni-A states of the [NiFe]-hydrogenases active site has been investigated using density functional theory and a reasonable structure for the spectroscopically well-characterized Ni-SIr andNi-SU species are proposed.

Maturation of [NiFe]-hydrogenases in Escherichia coli

The understanding of the initial steps in CN- synthesis have revealed that it is generated from carbamoyl phosphate, and it is becoming increasingly clear that the metabolic origins of the carbonyl group may be different.

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The structure and function of the iron-sulfur cluster-free hydrogenase (Hmd) is focused on and it is shown that this enzyme contains an iron-containing cofactor.

Approaches to efficient molecular catalyst systems for photochemical H2 production using [FeFe]-hydrogenase active site mimics.

Progresses in approaches to photochemical H(2) production using mimics of the [FeFe]-hydrogenase active site as catalysts in the last three years are reviewed, with emphasis on adjustment of the redox potentials and hydrophilicity of the active site mimics to make them efficient catalysts for H( 2) production.

An iron-iron hydrogenase mimic with appended electron reservoir for efficient proton reduction in aqueous media

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Oxygen tolerance of an in silico-designed bioinspired hydrogen-evolving catalyst in water

Demonstration by ab initio simulations that the [FeFe]P/FeS2 catalyst/electrode complex is indeed tolerant to dissolved oxygen over timescales long enough for practical application, reducing it efficiently.

[FeFe]-hydrogenases and photobiological hydrogen production

Computational simulations of gas diffusion within the Clostridium pasteurianum CpI hydrogenase are reviewed and the protein structure at specific sites along the O2 pathways are modified by site-directed mutagenesis with the goal of generating recombinant enzymes with higher O2 tolerance.



Chemistry and the hydrogenases.

The reversible reduction protons to dihydrogen: 2H+ + 2e [symbol: see text] H2 is deceptively the simplest of reactions but one that requires multistep catalysis to proceed at practical rates. How

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[Fe]-Hydrogenase II isolated from C. pasteurianum contains 14 Fe which are distributed among the so-called H cluster (the catalytic center) and two [4Fe-4S] clusters. Insights gained from Mossbauer

The di-iron subsite of all-iron hydrogenase: mechanism of cyanation of a synthetic [2Fe3S]-carbonyl assembly.

Stopped-flow FTIR spectroscopy has enabled the quantitation of the dynamics of five well-defined steps that experimentally illustrate the role of bridging carbonyls in the assembly of the dicyanide species, how on-off sulfur ligation can have a dramatic effect on cyanation kinetics and how the [2Fe3S] core stabilises bridgingcarbonyl species.

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First Generation Analogues of the Binuclear Site in the Fe-Only Hydrogenases: Fe2(μ-SR)2(CO)4(CN)22-

Having cyanide and CO coligands as well as metal-metal bonding, the hydrogenase active sites represent a link between the otherwise disparate realms of organometallic and biological Fe-S chemistry.

Density functional theory investigation of the active site of Fe-hydrogenases. systematic study of the effects of redox state and ligands hardness on structural and electronic properties of complexes related to the [2Fe](H) subcluster.

Results show that the structural and electronic properties of fully reduced Fe(i)Fe(I) complexes are strongly affected by the nature of the ligand L, and in particular, a progressive rotation of the Fe(d)(CO)(2)(CN) group, with a CO ligand moving from a terminal to a semibridged position, is observed going from the softest to the hardest ligand.

Modeling the active sites in metalloenzymes. 3. Density functional calculations on models for [Fe]-hydrogenase: structures and vibrational frequencies of the observed redox forms and the reaction mechanism at the Diiron Active Center.

  • Z. CaoM. Hall
  • Chemistry
    Journal of the American Chemical Society
  • 2001
The oxidation states and structures for the diiron active site are proposed, and a proposed reaction mechanism (catalytic cycle) based on the DFT calculations shows that heterolytic cleavage of H(2) can occur from (eta(2)-H(2)) Fe(II)-Fe(II) via a proton transfer to "spectator" ligands.

Carbon Monoxide and Cyanide Ligands in a Classical Organometallic Complex Model for Fe-Only Hydrogenase.

The Fe(I) organometallic complex provides a structural model for the cyano-carbonyl diiron site of Fe-only hydrogenase as characterized by X-ray crystallography.

A di-iron dithiolate possessing structural elements of the carbonyl/cyanide sub-site of the H-centre of Fe-only hydrogenase

The synthesis and characterisation of the first {2Fe2S}-cluster bearing both CO and CN ligands is described; the iron atoms are linked by the bridging 1,3-propanedithiolate unit that has been