Sökning: "proton transfer pathway"

Visar resultat 11 - 15 av 27 avhandlingar innehållade orden proton transfer pathway.

  1. 11. Experimental studies of proton translocation reactions in biological systems : Electrogenic events in heme-copper oxidases

    Författare :Håkan Lepp; Peter Brzezinski; Thomas Nilsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; heme-copper oxidase; cytochrome c oxidase; nitric oxide reductase; cbb3-type oxidase; proton pumping; uncoupling; charge-transfer; electrogenic event; flow-flash; Biophysics; Biofysik; Biophysics; biofysik;

    Sammanfattning : Terminal heme-copper oxidases (HCuOs) are transmembrane proteins that catalyze the final step in the respiratory chain - the reduction of O2 to H2O, coupled to energy conservation by generation of an electrochemical proton gradient. The most extensively investigated of the HCuOs are the aa3-type oxidases, to which cytochrome c oxidase (CytcO) belongs, which uses energy released in the O2-reduction for proton pumping. LÄS MER

  2. 12. Deciphering the Mechanistic Diversity of Proton-Coupled Electron Transfer Reactions

    Författare :Robin Tyburski; Leif Hammarström; Thomas Moore; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PCET; Proton Coupled Electron Transfer;

    Sammanfattning : Proton coupled electron transfer is ubiquitous in biological and artificial reaction systems. Much has been done in order to describe the occurrence of such reactions. However, PCET reactivity is often very complex. For instance, there are multiple (stepwise and concerted) mechanistic pathways through which PCET may occur. LÄS MER

  3. 13. Prokaryotic respiratory supercomplexes : Studies of interactions between complexes III and IV

    Författare :Olga Stah; Pia Ädelroth; Petra Hellwig; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; bioenergetics; membrane protein; bacterial respiration; electron transport chain; supercomplex; cytochrome c oxidase; membrane-anchored cytochrome c; cytochrome bc1 complex; electron transfer; proton transfer; time-resolved spectroscopy; apoptosis; biokemi; Biochemistry;

    Sammanfattning : Respiratory processes for cellular energy conversion are carried out by the membrane-associated enzymes of the electron transfer chain (ETC). In recent years there has been emerging data showing that the members of the ETC organize into higher-level assemblies called supercomplexes (SCs) whose functional relevance is not yet fully understood. LÄS MER

  4. 14. Heme-copper oxidases and nitric oxide : Reaction mechanisms and supercomplex formation

    Författare :Ingrid Albertsson; Pia Ädelroth; Alessandro Giuffrè; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Heme-copper oxidase; nitrite reductase; nitric oxide reductase; nitric oxide; supercomplex; Paracoccus denitrificans; denitrification pathway; proton transfer pathway; C-type oxidase; Helicobacter pylori; Biochemistry; biokemi;

    Sammanfattning : In the denitrification process where nitrate is stepwise reduced to nitrogen gas, the toxic molecule nitric oxide (NO) is formed as an intermediate. Nitric oxide is produced by the enzyme cd1 Nitrite reductase (cd1NiR) by reduction of nitrite and is later reduced to nitrous oxide by nitric oxide reductase (cNOR). LÄS MER

  5. 15. Fingerprints of light-induced molecular transients : from quantum chemical models of ultrafast x-ray spectroscopy

    Författare :Jesper Norell; Michael Odelius; Sang-Kil Son; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; time-resolved x-ray spectroscopy; quantum chemistry; electronic structure; multi-configurational self-consistent field; density functional theory; molecular dynamics; Born-Oppenheimer dynamics; non-adiabatic dynamics; proton-transfer; charge-transfer; solvatization; Dyson orbital; teoretisk fysik; Theoretical Physics;

    Sammanfattning : Absorption of sunlight generates renewable electricity and powers the growth of plants, but also causes severe damage both to synthetic materials and biological tissue. The wildly varying outcomes of these light-induced processes are ultimately determined by much slighter differences in their underlying reaction pathways, induced by the transient properties of short-lived and miniscule molecules; a powerful approach to their detection and characterization is offered by ultrafast x-ray spectroscopy, with identification of spectral fingerprints and further guidance from quantum chemical models. LÄS MER