Search for dissertations about: "Iron III protoporphyrin IX"

Found 4 swedish dissertations containing the words Iron III protoporphyrin IX.

2. 1. An Investigation of Peroxidase Activity in Biomimetic and Biological Systems

   Author : Ekaterina Ryabova; Kemiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; metabolism; Metabolism; enzymologi; Proteiner; enzymology; Proteins; hemoglobin; catalysis; peptide; peroxidase; protoporphyrin IX; Biokemi; Biochemistry;

   Abstract : In order to create a heme environment which permits biomimicry of heme-containing plant peroxidases and investigate the role played by the vinyl side chains of the porphyrin ring on the stability and, possibly, catalytic activity of model compounds, a number of new synthetic microperoxidases -– hemin-6(7)-gly-his methyl ester (HGH) and hemin-6(7)-gly-gly-his methyl ester (HGGH) and hemin-6,7-bis(gly-gly-his methyl ester) (H2GGH) as well as mesohemin-6(7)-gly-gly-his methyl ester (MGGH) and deuterohemin-6(7)-gly-gly-his methyl ester (DGGH) have been prepared by condensation of a peptide residue with the propionic side chains of hemin, mesohemin and deuterohemin, respectively. Reactivity studies towards different organic and inorganic substrates showed that not only five- but also six-coordinate hemin peptide complexes catalyze the oxidation of substrates by H2O2. READ MORE

4. 2. Tetrapyrrole synthesis in Bacillus subtilis

   Author : Mats Hansson; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : This thesis describes tetrapyrrole synthesis in the aerobic Gram positive bacterium Bacillus sub-tilis. Tetrapyrroles such as heme of a-, b-, c-, d- and o-type can be synthesised in this organism. In addition, there is strong evidence for the presence of the tetrapyrrole siroheme in B. subtilis. READ MORE

5. 3. Theoretical studies of porphyrin proteins

   Author : Emma Sigfridsson; Beräkningskemi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; molecular mechanics; quantum chemical calculations; electrostatic potential charges; atomic charges; ferrochelatase; cytochrome; myoglobin; Porphyrin; haem; QM MM; reorganisation energy; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi;

   Abstract : Different aspects of porphyrin proteins have been studied with theoretical methods. For example, we have studied: - The importance of hydrogen bonds for the discrimination between carbon monoxide and molecular oxygen by myoglobin, the oxygen carrier in muscles, modelling the active site both in vacuum and in the protein matrix - The inner-sphere reorganisation energy during electron transfer for cytochromes compared to other electron-transfer proteins, such as blue copper proteins and Fe-S clusters - The role of porphyrin distortions in the reaction mechanism of ferrochelatase, the enzyme that inserts an iron ion into protoporphyrin IX to make haem - The interaction between different metal sites in ferrochelatase In these studies we have used density functional theory, classical force field methods, and a combination of quantum chemistry and molecular mechanics. READ MORE

6. 4. Magnesium Chelatase: Insights into the first Step of Chlorophyll Biosynthesis

   Author : Nick Sirijovski; Biokemi och Strukturbiologi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electron microscopy; Proteobacteria; Mutants; Rhodobacter capsulatus; Tetrapyrrole; Plant biochemistry; Växtbiokemi; Biochemistry; Metabolism; Biokemi; metabolism; Proteins; enzymologi; enzymology; Proteiner; Chlorophyll biosynthesis; AAA proteins; Magnesium chelatase; Barley; ATPase;

   Abstract : The enzyme magnesium chelatase inserts magnesium into protoporphyrin IX (Proto) to produce to magnesium protoporphyrin IX, the first unique intermediate of the chlorophyll biosynthetic pathway. Magnesium chelatase is composed of three distinct proteins termed I (molecular weight ~40 kDa), D (~70 kDa) and H (~140 kDa). READ MORE