Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 64 for “"NiFe"”.
-
Investigating [NiFe]-hydrogenases in γ-Proteobacteria
… One well studied, ancient group is termed the [NiFe]-hydrogenases, which all harbour a complex NiFe(CN-)2CO active site in the ‘large’ catalytic subunit and usually have three iron-sulfur clusters within a ‘small’ electron transferring partner subunit. [NiFe]-hydrogenases have undergone massive …
-
Ultrafast dynamics of [NiFe] hydrogenase models
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-05-01
-
Investigation of Escherichia coli [NiFe]-Hydrogenase Maturation
[NiFe]-hydrogenases catalyze the reversible oxidation of hydrogen gas at a bimetallic active site and are important enzymes in bacteria and archaea for anaerobic growth and pathogenesis. The maturation of [NiFe]-hydrogenase requires at least seven dedicated accessory proteins to assemble and insert …
-
Modeling The Active Site Of [NiFe]-Hydrogenase
… be on the first hydrogenase to be evolved, the [NiFe]-hydrogenase, which contains a heterobimetallic NiFe active site. The [NiFe]- hydrogenase is a heterodimeric enzyme, and it is composed of a large subunit and a small subunit, inside the large subunit is buried the active site deep within the …
-
Mutagenesis of nifE and nifN from Azotobacter vinelandii
The products of nifE and nifN from Azotobacter vinelandii, which are involved in the biosynthesis of the iron-molybdenum cofactor (FeMo-co) co) from nitrogenase, have been analyzed using a variety of mutagenic techniques. NifE was the object of several site-specific, amino acid substitutions that …
-
Biosynthese des Metallzentrums von [NiFe]-Hydrogenasen aus E. coli
In dieser Arbeit wurden drei Aspekte der Reifung der Hydrogenasen in E. coli näher untersucht: 1. Eine Deletion im carAB-Locus führt zum Verlust der Synthese aktiver Hydrogenasen in E. coli. Die Aktivität kann wiederhergestellt werden, wenn der Stamm mit einem carAB-tragenden Plasmid transformiert …
-
Vibrational spectroscopic studies on [NiFe] hydrogenases: insights into structure and function
… catalytic subunit HoxG of the membrane-bound [NiFe]-hydrogenase from Cupriavidus necator, lacking the [Fe-S] cluster-containing small subunit HoxK, has been subjected to detailed spectroscopic investigations. This project revealed so far unknown maturation intermediates of the stepwise …
-
Incorporation of cyanide ligands into models of [FeFe]- and [NiFe]-hydrogenase
… hydrogenase enzymes are bimetallic with FeFe or NiFe active sites. The metals of the active sites are bound to carbonyl and cyanide ligands with the metal centers bridged by thiolates. The use of inexpensive and readily available elements by hydrogenase enzymes has been a driving force for the …
-
Funktion, Modifikation und Anwendung von O2-toleranten, NAD(P)+-reduzierenden [NiFe]-Hydrogenasen
Lösliche, NAD(P)+-abhängige [NiFe]-Hydrogenasen („Soluble Hydrogenase“, SH) katalysieren die reversible Spaltung von H2 in jeweils zwei Elektronen und Protonen sowie die damit gekoppelte Reduktion des Pyridinnukleotid-Kofaktors. Die beiden Reaktionen erfolgen in zwei unterschiedlichen Modulen, dem …
-
Hydrogen production from model complexes of the [FeFe]- and [NiFe]-hydrogenase active sites
… hydrogen from protons and electrons, while the [NiFe]-hydrogenases function to oxidize hydrogen. The active sites of both enzymes contain first-row transition metals and biologically exotic ligands. When assayed for their rates and efficiencies of hydrogen processing, the hydrogenase enzymes are …
-
Genetic analysis of nifF and nifA and site-directed mutagenesis of nifE in Azotobacter vinelandii
… transport), nifA (nif gene regulation) and nifE (FeMo-cofactor biosynthesis) genes from <i>Azotobacter vinelandii</i> were genetically analyzed. The nucleotide sequence of the nifF gene, which encodes a flavodoxin, was determined. Specific mutation strains indicated that in <i>A …
-
Biochemical and spectroscopic insights into peculiar active site structures and biosynthesis of O2-tolerant [NiFe]-hydrogenases
[NiFe]-hydrogenases are metalloenzymes catalyzing the reversible cleavage of H2 into two H+ and two e–. They are particularly interesting for clean and sustainable H2-based energy conversion approaches or the H2-driven regeneration of nucleotide cofactors. Their active site consists of a …
-
Propiedades y dependencia composicional de las transformaciones martensíticas en intermetálicos metaestables basados en MnCo(Fe)Ge(Si) y NiFe(Co)Ga
… de materiales basados en sistemas del tipo NiFeGa(Co) y Mn(CoFe)(GeSi)(B), con el fin de comprender sus transformaciones magnetoestructurales y las propiedades térmicas y magnéticas asociadas. Se prestará especial atención a la relación existente entre composición y microestructura, que son …
-
Investigating direct alkaline seawater electrolysis and its impact on the oxygen evolution reaction
… characterisation techniques is presented. NiFe(OH)2 exhibits high OER activity in alkaline simulated seawater, requiring 327 and 393 mV to achieve 500 and 1000 mA cm-2 respectively at 298 K during initial testing. However, accelerated degradation and post-testing characterisation reveal …
-
Ultrasoft magnetic materials processing and characterisation
… shown to improve the magnetic properties of the NiFe alloy. The aim of this research was further to test this process on alloys such as CoNiFe as well as integrating these ‘ultrasoft’ magnetic materials into on-chip micro-inductors for device functionality testing. A material with a hysteresis of …
-
Giant Magneto-impedance Effect In Thin Film Layered Structures
… and processing conditions for CoSiB and NiFe thin films to obtain the soft magnetic properties and to evaluate their potential use in GMI sensor applications. Prior to this study, an MH Looper was constructed, which was extremely important and provided the basic magnetic characterization …
-
Metallic Magnetic Hetrostructures
… condition that permitted EB to be established in NiFe/FeMn but not in FeMn/Co bilayer structures. Temperature-dependent magnetic measurements were performed on the trilayer sample, as well as the corresponding NiFe/FeMn and FeMn/Co bilayer samples. Recent literature on similar system showed that …
-
Magnetic properties of lithographically patterned thin film magnetic elements for magnetic random access memory applications
… periodic rectangular patterns. Single layer Co, NiFe, and multilayer Co/Cu/NiFe pseudo spin valve films have been patterned into series of element arrays with different sizes. With the aim of assessing the behavior of future magnetic random access memory (MRAM) devices, the magnetic properties of …
-
Mixed-valence bimetallic dithiolates of iron, cobalt, and nickel and their relevance to the hydrogenases
… metals nickel and iron. The active sites the [NiFe]- and [FeFe]-H2ases possess bimetallic cores bridged by thiolates. The iron centers are ligated by species that are peculiar in biological systems: carbon monoxide and cyanide. Due to the effectiveness of H2ases as H2 oxidation proton reduction …
Page 1 of 4