Sökning: "enzymatic mechanism"

Visar resultat 11 - 15 av 162 avhandlingar innehållade orden enzymatic mechanism.

1. 11. Insights into enzymatic thiamin catalysis

   Författare :Christer Wikner; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :thiamin; transketolase; catalysis; catalytic mechanism; site-directed muta genesis; enzyme kinetics; circular dichroism Christer Wikner; Molecular Structural Biology; Dept. of Medical Biochemistry and Biophysics; Karolinska Institutet; S-171 77 Stoc;

   Sammanfattning : Thiamin diphosphate, the biologically active form of vitamin B,, functions as a cofactor in various enzymes in the cell. The protein enhances the reactivity of the cofactor by binding it in a very specific manner. LÄS MER

3. 12. Enzymatic metal-chelation by porphyrins

   Författare :Andreas Hansson; Biokemi och Strukturbiologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tetrapyrrole; Plant biochemistry; Växtbiokemi; MIDAS; metallation; magnesium chelatase; integrin; heme; ferrochelatase; chlorophyll; barley; AAA ; ATPase;

   Sammanfattning : This thesis deals with the structure and function of two different enzymes, ferrochelatase and magnesium chelatase, that catalyse similar reactions. When this work started, a three-dimensional model of ferrochelatase existed. Much was known about the enzyme, but some details remained unclear. LÄS MER

4. 13. Biosynthesis of Dermatan Sulphate. Enzymatic mechanism and role of cytokines

   Författare :Kerstin Tiedemann; Institutionen för experimentell medicinsk vetenskap; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Dermatan sulphate; 4-O-sulfotransferase; Co-polymeric structure; biglycan; decorin; Biochemistry; Biokemi; C5-epimerase; Metabolism;

   Sammanfattning : Dermatan sulphate is a prominent feature of several different proteoglycans and occurs in almost every tissue of the body. It is an unbranched polymer containing the repeating disaccharide unit of N-acetylgalactosamine and D-glucuronic acid or L-iduronic acid. LÄS MER

5. 14. Assembly and Function of Nitric Oxide Reductase from Paracoccus denitrificans

   Författare :Maximilian Kahle; Pia Ädelroth; Hans-Georg Koch; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; non-heme iron; cofactor; heme-copper oxidase; AAA ; cNOR; chaperone; metal ion insertion; MoxR; nor accessory genes; FeB; liposomes; membrane mimetics; nanodiscs; reconstitution; enzymatic mechanism; NO reduction; O2 reduction; Biochemistry; biokemi;

   Sammanfattning : Bacterial denitrification is a part of the global nitrogen cycle and comprises the stepwise reduction of nitrate to molecular nitrogen, which is released to the atmosphere. Cytochrome c-dependent nitric oxide reductase (cNOR) from Paracoccus (P.) denitrificans catalyzes the reduction of nitric oxide to nitrous oxide and water. LÄS MER

7. 15. Computational Studies of Enzymatic Enolization Reactions and Inhibitor Binding to a Malarial Protease

   Författare :Isabella Feierberg; Modesto Orozco; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Theoretical chemistry; enzyme mechanism; enolate; molecular dynamics; empirical valence bond; glyoxalase I; ketosteroid isomerase; triosephosphate isomerase; malaria; aspartic protease; plasmepsin; linear interaction energy; drug design; Teoretisk kemi; Theoretical chemistry; Teoretisk kemi; Molecular Biotechnology; Molekylär bioteknik;

   Sammanfattning : Enolate formation by proton abstraction from an sp3-hybridized carbon atom situated next to a carbonyl or carboxylate group is an abundant process in nature. Since the corresponding nonenzymatic process in water is slow and unfavorable due to high intrinsic free energy barriers and high substrate pKa s, enzymes catalyzing such reaction steps must overcome both kinetic and thermodynamic obstacles. LÄS MER