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Showing 1 to 15 of 15 for “"[FeFe] hydrogenase"”.
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Hydrides in [FeFe]-hydrogenase model complexes
The student, Michaela Carlson, submitted this Dissertation for approval on 2018-04-17 at 10:07.
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Synthetic models of [FeFe]-hydrogenase: case studies utilizing azadithiolate and nitrosyl coligands
Hydrogenases are enzymes that catalyze the reversible interconversion of protons, electrons, and dihydrogen (2H+ + 2e− <-> H2). Because of the potential utility of H2 as an energy carrier, the detailed understanding of hydrogenases has received considerable attention and funding. In particular, …
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Identification and description of Clostridium sp. and metabolic activities in fermentative hydrogen production
… three hydrogen producers, which harboured the [FeFe] hydrogenase gene, were characterised by 16S rDNA sequencing, and further physiologically identified as Clostridium sp. (W1), Clostridium butyricum (W4) and Clostridium butyricum (W5). The structure of the putative [FeFe] hydrogenase gene …
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Modeling the Active Sites of [nickel-Iron]- and [iron-Iron]-Hydrogenases
While previous hydride-containing [FeFe]-hydrogenase models featured only bridging hydrides, we sought to prepare complexes of terminal hydrides that would be more relevant to mimicking this hydrogenase. Di-subferrous precursors, such as Fe2(S2C2H4)(CO)4 (PMe3)2, have been known for decades---well …
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A combined approach of electronic structure calculations and spectroscopy for elucidating reaction mechanisms in organic and bioinorganic systems
… and energy harvesting. The mechanisms by which [FeFe] and [NiFe] hydrogenase enzymes catalyse the reversible reduction of protons to dihydrogen are of intrinsic interest in the context of a developing hydrogen technology for energy transduction. Gas phase DFT calculations are used to simulate and …
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Chemistry related to the actives sites of the [Fe]- and [FeFe]-hydrogenases
Hydrogenases are an important group of enzymes found in a range of microorganisms. There are three phylogenetically distinct classes of hydrogenase all of which feature iron-containing complexes. The work contained in this thesis has two main focuses: the synthesis and characterization of novel …
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Metabolic and molecular responses to interspecies hydrogen transfer between Ruminococcus albus and Wolinella succinogenes
… bacterium with two known hydrogen-producing hydrogenase complexes, HydABC and HydA2, as well as a putative hydrogen-sensing protein, HydS. HydABC is the only chromosomal hydrogenase, while HydA2 and HydS form a transcriptional unit on its plasmid pRumal01. The electron-bifurcating ferredoxin- …
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Hydrogen production from model complexes of the [FeFe]- and [NiFe]-hydrogenase active sites
… direction toward this goal, as enzymes called hydrogenases evolved several billion years ago to utilize molecular hydrogen as a fuel. The [FeFe]-hydrogenases predominately function to produce hydrogen from protons and electrons, while the [NiFe]-hydrogenases function to oxidize hydrogen. The …
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Novel infrared spectroscopic techniques for the study of adsorbed proteins on photoactive thin films
… of the enzyme of interest for this work (a [FeFe]-hydrogenase from Clostridium acetobutylicum), techniques were developed in a manner conducive to anaerobic environments. Solid-state ligand exchange processes were shown to have no detrimental effect on the continued ability of nanocrystal …
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Biohydrogen production in Escherichia coli – a synthetic biology approach
… at ambient temperatures by metal-dependent hydrogenase enzymes, with potentially no CO or H2S contamination, and is a carbon neutral/positive process.<br/>Escherichia coli naturally produces Bio-H2 during mixed-acid fermentation via its own endogenous nickel-dependent hydrogenase enzymes. …
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SECONDARY INTERACTIONS WHICH MODIFY REDOX AND OTHER PROPERTIES OF ORGANOMETALLIC SYSTEMS
… cyanide in a model for the diiron subsite of [FeFe]-hydrogenase. The natural subsite in its protein environment catalyses hydrogen evolution (or uptake) at very fast rates ca 104 s-1 near the reversible potential of the H+ /1/2 H2 couple but such rates have yet to be attained in model systems. …
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Molekulargenetische und reaktionskinetische Untersuchungen nativer und rekombinanter saccharolytischer Clostridien zur Optimierung der biologischen Wasserstoffproduktion
… were cloned by genome walk. The activity of the [FeFe]-hydrogenase could be demonstrated by its coexpression with the corresponding maturation proteins in E. coli BL21(DE3). Furthermore Thiolase was purified by affinity chromatography and its biochemical and kinetic properties were determined. The …
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Immobilising and Interfacing Poly(Heptazine Imide) Ionic Carbon Nitride for Photo(electro)catalytic Fuel and Chemical Production
… photoelectrochemical setup wired to a formate dehydrogenase (FDH) enzyme bio-cathode to perform selective CO2-to-formate conversion. Even under 1 sun, the bio-hybrid PEC system could withstand 10 hours of operation. Finally, the use of a [FeFe]-hydrogenase (H2-evolving enzyme) possessing a …
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Spectroscopic studies on hydrogenases
… is catalysed by a group of enzymes called hydrogenases. Members of this wide family of enzymes exhibit various properties, such as different activity rates, bias towards a specific direction of the catalytic reaction and a potential tolerance towards oxygen. Vibrational spectroscopy can be …
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Small molecule mimics of hydrogenase enzymes: synthesis, protonation, and electrocatalysis
In nature, H2 is processed by enzymes called hydrogenases, which catalyze the reduction of protons to dihydrogen, as well as the reverse reaction. The active sites of the two most prevalent hydrogenases contain NiFe or FeFe cores, bound to thiolates, cyanide, and carbon monoxide ligands. These …