Amine oxidase Dotaz Zobrazit nápovědu
Pharmacology and toxicology, ISSN 0901-9936 vol. 60, suppl. I, 1987
56, x s. ; 26 cm
- MeSH
- benzylaminoxidasa MeSH
- biochemie MeSH
- farmakologie MeSH
- monoaminoxidasa MeSH
- Publikační typ
- kongresy MeSH
- Konspekt
- Farmacie. Farmakologie
- NLK Obory
- farmacie a farmakologie
- toxikologie
- biochemie
Journal of pharmacy and pharmacology, ISSN 0022-3573 vol. 36, workshop suppl., November 1984
70W, ix s. : tab. ; 24 cm
- MeSH
- monoaminoxidasa MeSH
- Publikační typ
- kongresy MeSH
- Konspekt
- Farmacie. Farmakologie
- NLK Obory
- farmacie a farmakologie
- farmacie a farmakologie
APMIS, ISSN 0903-465X vol. 107, suppl. no. 96, 1999
46 s. : tab. ; 28 cm
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- biochemie
- biologie
The catalytic reaction of copper amine oxidase proceeds through a ping-pong mechanism comprising two half-reactions. In the initial half-reaction, the substrate amine reduces the Tyr-derived cofactor, topa quinone (TPQ), to an aminoresorcinol form (TPQamr) that is in equilibrium with a semiquinone radical (TPQsq) via an intramolecular electron transfer to the active-site copper. We have analyzed this reductive half-reaction in crystals of the copper amine oxidase from Arthrobacter globiformis. Anerobic soaking of the crystals with an amine substrate shifted the equilibrium toward TPQsq in an "on-copper" conformation, in which the 4-OH group ligated axially to the copper center, which was probably reduced to Cu(I). When the crystals were soaked with substrate in the presence of halide ions, which act as uncompetitive and noncompetitive inhibitors with respect to the amine substrate and dioxygen, respectively, the equilibrium in the crystals shifted toward the "off-copper" conformation of TPQamr. The halide ion was bound to the axial position of the copper center, thereby preventing TPQamr from adopting the on-copper conformation. Furthermore, transient kinetic analyses in the presence of viscogen (glycerol) revealed that only the rate constant in the step of TPQamr/TPQsq interconversion is markedly affected by the viscogen, which probably perturbs the conformational change. These findings unequivocally demonstrate that TPQ undergoes large conformational changes during the reductive half-reaction.
- MeSH
- arteriae mesentericae enzymologie MeSH
- diabetes mellitus 2. typu enzymologie MeSH
- financování organizované MeSH
- histaminasa analýza metabolismus MeSH
- kinetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- monoaminoxidasa analýza metabolismus MeSH
- noradrenalin metabolismus MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
