Sökning: "magnetic relaxation dispersion"

Visar resultat 1 - 5 av 20 avhandlingar innehållade orden magnetic relaxation dispersion.

  1. 1. Water and protein solutions studied by field-dependent magnetic relaxation

    Författare :Kristofer Modig; Biofysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; relaxation; protein solvation; protein dynamics; protein denaturation; oxytocin; magnetic relaxation dispersion; nuclear magnetic resonance; lipid-binding protein; hydration; beta-lactoglobulin; BPTI; shielding anisotropy; water; Molecular biophysics; Molekylär biofysik;

    Sammanfattning : In the work presented, nuclear magnetic resonance (NMR) relaxation is used to study wide range of systems. The thesis concerns solvent interactions studied with relaxation techniques that involve measurements at many fields, which allows the separation of individual relaxation mechanisms. LÄS MER

  3. 2. Water and Protein Dynamics in Biological Systems Studied by Magnetic Relaxation Dispersion

    Författare :Erik Persson Sunde; Biofysikalisk kemi; []
    Nyckelord :protein dynamics; ubiquitin; BPTI; Escherichia coli; Haloarcula marismortui; nuclear magnetic resonance; protein hydration; magnetic relaxation dispersion; water dynamics; cell water;

    Sammanfattning : The results presented in this thesis demonstrate that the magnetic relaxation dispersion (MRD) technique can provide information of relevance to protein biophysics, magnetic resonance imaging and cell biology. By immobilizing proteins with covalent cross-links, intermittent protein dynamics on the previously inaccessible ns-µs time scale could be probed with MRD via the exchange of water molecules between internal cavities and the surrounding bulk solvent phase. LÄS MER

  4. 3. Theory of water-proton spin relaxation in complex biological systems

    Författare :Zhiwei Chang; Biofysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spin relaxation theory; immobilized macromolecules; magnetic relaxation dispersion; integral longitudinal relaxation rate; stochastic Liouville equations; multi-spin systems; cross-mode relaxation; spectral density functions;

    Sammanfattning : In complex biological systems (e.g. gels, cross-linked proteins and biological tissues), the longitudinal spin relaxation of water protons is primarily induced by exchange-mediated orientational randomization (EMOR) of intra- and intermolecular magnetic dipole-dipole couplings. LÄS MER

  5. 4. Magnetic relaxation studies of self-associating and membrane proteins

    Författare :Michael Gottschalk; Lund University Bioimaging Center; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; beta-lactoglobulin A; Biokemisk teknik; Biochemical technology; HEWL; BPTI; bacteriorhodopsin; protein self-association; membrane proteins; NMR; magnetic relaxation dispersion;

    Sammanfattning : Magnetic relaxation dispersion measurements have been performed on aqueous protein solutions to study the dynamics of waters in the proton transport channel of bacteriorhodopsin and the self-association of the proteins BPTI, lysozyme and beta-lactoglobulin. The measurements have focused on the bulk relaxation rates, R1 and R2, of three water nuclei 1H, 2H and 17O that are coupled to the protein environments by exchange and therefore report on properties such as the protein tumbling and dynamics of internal waters. LÄS MER

  7. 5. Probing Dynamics of Oligosaccharides by Interference Phenomena in NMR Relaxation

    Författare :Leila Ghalebani; Jozef Kowalewski; Norbert Mueller; Stockholms universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NMR; sugars; oligosaccharides; carbon-13 relaxation; cross-correlated relaxation; molecular dynamics; internal motion; random jumps; PRE; paramagnetic relaxation; Chemistry; Kemi; fysikalisk kemi; Physical Chemistry;

    Sammanfattning : Oligosaccharides (carbohydrates) are a large class of biological molecules that are important as energy sources in the human body and have enormously varied biological functions. It is generally believed that biological activities of carbohydrates are related to their internal dynamics. LÄS MER