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Visar resultat 1 - 5 av 106 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Ultrafast Structural Changes in a Bacterial Photosynthetic Reaction Center probed with XFEL Radiation

    Författare :Robert Dods; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photosynthesis; Reaction Center; Time-resolved crystallography; XFEL; membrane protein;

    Sammanfattning : Photosynthesis is the process by which plants and many species of bacteria convert energy from sunlight into chemical energy used to power their metabolism. As these plants and bacteria are eaten, the chemical energy moves up the food chain and thus photosynthesis provides fuel for almost all life on Earth. LÄS MER

  2. 2. Structural Insights at Sub-Ångstrom, Medium and Low Resolution: Crystallization of Trypsin, Bacterioferritin, Photosynthetic Reaction Center, and Photosynthetic Core Complex

    Författare :Weixiao Yuan Wahlgren; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; protein crystallization; cubic phase; sponge phase; bicelle; trypsin; bacterioferritin; reaction center; core complex; photosynthesis;

    Sammanfattning : The catalytic action of serine proteases depends on the interplay of a nucleophile, a general base and a general acid. The catalytic triad is composed of serine, histidine and aspartate residues. The serine acts as a nucleophile while the histidine plays a dual role as the general base or acid at different steps of the reaction. LÄS MER

  3. 3. X-ray free-electron laser based methods for structural and ultrafast dynamics studies of a photosynthetic reaction centre

    Författare :David Arnlund; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; WAXS; wide-angle x-ray scattering; XFEL; x-ray free-electron laser; reaction center; structural biology; ultrafast dynamics;

    Sammanfattning : Life on earth is fuelled by the energy of sunlight, which must first be captured and converted into a chemical energy form useful to the cell. This process is known as photosynthesis and the major pathway of this energy conversion is via photosynthetic reaction centres. LÄS MER

  4. 4. High-resolution measurement of the ¹⁶O(γ,pn) reaction

    Författare :Lennart Isaksson; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pn ; E_gamma = 67-76 MeV; resolved states; cross-sections; Nuclear physics; Kärnfysik; Fysicumarkivet A:1996:Isaksson; 16O gamma; Photonuclear reaction;

    Sammanfattning : The 16O(gamma,pn) reaction has been measured with a resolution high enough to resolve individual low-lying states in the residual 14N nucleus. The relative population of the states provides detailed information about the quantum numbers of the proton-neutron pairs on which photons are absorbed. LÄS MER

  5. 5. Studies of the anomeric center : mechanism and synthesis

    Författare :Karl-Jonas Johansson; Harri Lönnberg; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic Chemistry; organisk kemi;

    Sammanfattning : This thesis is based on three publications and one appendix and is divided into two parts. The first part is a mechanistic study of the anomerization reaction of both aldo and keto glycosides and the second part is a synthetic study of a unusual type of glycosidic linker found in the lipopolysaccharide core Proteus Mirabilis 0270. LÄS MER