Search for dissertations about: "iron enzymes"

Showing result 1 - 5 of 55 swedish dissertations containing the words iron enzymes.

  1. 1. Manganese and Iron Heterodimers and Homodimers in Enzymes : Insights from Density Functional Theory

    Author : Katarina Roos; Per Siegbahn; Margareta R. A. Blomberg; Frank Neese; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ribonucleotide reductase; manganese; iron; density functional theory; kemisk fysik; Chemical Physics;

    Abstract : The enzyme ribonucleotide reductase (RNR) catalyzes the reduction of ribonucleotides to deoxyribonucleotides, the building blocks of DNA, and is essential for all organisms. Canonical class I RNR R2 proteins use a diiron cofactor to generate a tyrosyl radical, which is required for catalysis. READ MORE

  2. 2. Atom and Group Transfer Reactions Involving High-valent Iron Complexes

    Author : Yong Li; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Iron enzymes; high-valent iron intermediates; bio-inspired iron complexes; FeIV=O; FeIV=NR; catalytic reactions; electronic effects; steric restriction.;

    Abstract : Iron enzymes play critical roles in biological oxidation reactions by utilizing highly reactive high-valent iron intermediates, such as FeIV=O, FeV(O)(OH), and FeIV=NR species, for catalytic reactions. These intermediates exhibit remarkable catalytic behavior with high reactivities and high regio- and stereospecificity in various biochemical reactions. READ MORE

  3. 3. Biomimetic Iron Complexes involved in Oxygenation and Chlorination : A Theoretical Study

    Author : Holger Noack; Margareta R. A. Blomberg; Per E. M. Siegbahn; Martin Kaupp; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; biomimetic; iron; density functional theory; intradiol; chlorination; adpic acid; diamond core; reactivity; Bio-inorganic chemistry; Bio-oorganisk kemi; Theoretical chemistry; Teoretisk kemi; kemisk fysik; Chemical Physics;

    Abstract : Biomimetic chemistry is directed towards the simulation of enzymatic reactivity with synthetic analogues. In this thesis a quantum chemical method has been employed to study the mechanism of highly reactive iron-oxo complexes involved in oxygenation and chlorination of organic substrates. READ MORE

  4. 4. Functional Models for Non-heme Mononuclear Iron Oxygenases

    Author : Mainak Mitra; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Bioinorganic chemistry; Iron; Oxygenases; Catalysis;

    Abstract : Non-heme mononuclear iron oxygenases catalyze a large number of oxidation reactions in biological systems. The reactions are often proposed to proceed via the intermediacy of high valent Fe(IV) oxo (ferryl) or, Fe(V) oxo (perferryl) intermediates. READ MORE

  5. 5. Theoretical studies of mononuclear non-heme iron active sites

    Author : Arianna Bassan; Per E. M. Siegbahn; Sason Shaik; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; quantum chemistry; enzyme catalysis; iron enzymes; Quantum chemistry; Kvantkemi;

    Abstract : The quantum chemical investigations presented in this thesis use hybrid density functional theory to shed light on the catalytic mechanisms of mononuclear non-heme iron oxygenases, accommodating a ferrous ion in their active sites. More specifically, the dioxygen activation process and the subsequent oxidative reactions in the following enzymes were studied: tetrahydrobiopterin-dependent hydroxylases, naphthalene 1,2-dioxygenase and α-ketoglutarate-dependent enzymes. READ MORE