Visar resultat 1 - 5 av 130 avhandlingar innehållade ordet peroxidase.
Sammanfattning : 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. LÄS MER
2. Studies of Electrocatalytic Reactions of NADH at Mediator Modified Electrodes and of H2O2 at Peroxidase Modified Electrodes
Sammanfattning : This thesis addresses: (1) studies of direct and mediated electron transfer and kinetics of peroxidases on electrodes and the development of amperometric peroxidase-based biosenors, (2) electrochemical and kinetic studies of NADH oxidation at mediator modified electrodes. The direct and mediated electron transfer of horseradish and tobacco peroxidase were investigated on graphite electrodes by using wall-jet electrode methodology. LÄS MER
Sammanfattning : The function of non-vertebrate haemoglobins (Hbs) appears more diverse than that of vertebrate Hbs, possibly reflecting the various demands to be met among their hosts. Sharing structural features with other haem proteins/enzymes, Hbs display a qualitative overlap in activities with functions extending beyond oxygen transport/storage. LÄS MER
Sammanfattning : The thesis is a bioelectrochemical study of heme enzymes, mainly peroxidases and cellobiose dehydrogenases (CDH). It covers both fundamental and applied aspects, viz. studies of the direct electron transfer and kinetics of enzymes on electrodes, and the development of amperometric enzyme-based biosensors. LÄS MER
Sammanfattning : The capacity of somatic cells and pollen grains or microspores to undergo embryogenesis is an important property used in improvement and regeneration of plants. Furthermore, somatic embryogenesis as well as pollen embryogenesis show many similarities with zygotic embryogenesis and are, thus, good model systems. LÄS MER