FTIR spectroelectrochemical study of the activation and inactivation processes of [NiFe] hydrogenases: effects of solvent isotope replacement and site-directed mutagenesis
| Autor: | Sebastian Dementin, Alejandro Pardo, Antonio L. De Lacey, Marc Rousset, Victor M. Fernandez, E. Claude Hatchikian, Géraldine Adryanczyk-Perrier |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Hydrogenase
Kinetics Glutamic Acid Photochemistry Biochemistry Inorganic Chemistry Isotopes Metalloproteins Spectroscopy Fourier Transform Infrared Kinetic isotope effect Metalloprotein Desulfovibrio gigas Anaerobiosis Site-directed mutagenesis chemistry.chemical_classification Binding Sites biology Active site Solvent chemistry Mutagenesis Site-Directed Solvents biology.protein Hydrogen |
| Zdroj: | JBIC Journal of Biological Inorganic Chemistry. 9:636-642 |
| ISSN: | 1432-1327 0949-8257 |
| Popis: | The kinetics of the activation and anaerobic inactivation processes of Desulfovibrio gigas hydrogenase have been measured in D(2)O by FTIR spectroelectrochemistry. A primary kinetic solvent isotope effect was observed for the inactivation process but not for the activation step. The kinetics of these processes have been also measured after replacement of a glutamic residue placed near the active site of an analogous [NiFe] hydrogenase from Desulfovibrio fructosovorans. Its replacement by a glutamine affected greatly the kinetics of the inactivation process but only slightly the activation process. The interpretation of the experimental results is that the rate-limiting step for anaerobic inactivation is the formation from water of a micro-OH(-) bridge at the hydrogenase active site, and that Glu25 has a role in this step. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|