Sökning: "Porphyrin"

Visar resultat 1 - 5 av 83 avhandlingar innehållade ordet Porphyrin.

  1. 1. Theoretical studies of porphyrin proteins

    Författare :Emma Sigfridsson; Teoretisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 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;

    Sammanfattning : 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. LÄS MER

  2. 2. Intramolecular processes in porphyrin-based donor-bridge-acceptor systems

    Författare :Karin Pettersson; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Donor-bridge-acceptor system; paramagnetic species; spectroscopy; porphyrin; super-exchange electron transfer; sequential electron transfer;

    Sammanfattning : .... LÄS MER

  3. 3. Multimodal Porphyrin-Based Conjugates : Synthesis and characterization for applications as amyloid ligands, photodynamic therapy agents and chiroptical materials

    Författare :Katriann Arja; Peter Nilsson; Peter Konradsson; Fredrik Almqvist; Linköpings universitet; []

    Sammanfattning : Organic compounds that interact both with certain biological targets and display specific photophysical properties can be utilized as molecular tools to visualize and possibly effect disease related processes taking place in living organisms. In this regard, porphyrins are a class of naturally occurring molecules that possess intriguingly interesting photophysical properties where they can act as luminescent probes by emitting detectable light, as well as photosensitizers in the light mediated therapy called photodynamic therapy. LÄS MER

  4. 4. Crystallographic studies on porphyrin metallation by ferrochelatase

    Författare :David Lecerof; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; thermal and mechanical properties; Condensed matter:stucture; fasjämvikt; kristallografi; egenskaper termiska och mekaniska ; Kondenserade materiens egenskaper:struktur; crystallography; phase equilibria; Magnesium; pi-helix; Zinc; ferrochelatase; Metal binding; porphyrin metallation;

    Sammanfattning : Ferrochelatase catalyses the terminal step in heme biosynthesis by inserting a ferrous ion into protoporphyrin IX. The reaction mechanism has in this thesis been studied by mainly crystallographic methods. LÄS MER

  5. 5. Influence of Bridge Structures on the Electron Transfer in Donor-Acceptor Systems

    Författare :Mikael Winters; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; molecular wire; electron transfer; porphyrin; conjugated oligomer;

    Sammanfattning : In this Thesis, porphyrin-based donor-acceptor systems have been used to study photoinduced electron transfer processes. Principally, two different sets of systems have been investigated. LÄS MER