Regulatory properties of pyridine-nucleotide transhydrogenase from pseudomonas-aeruginosa. Kinetic studies and fluorescence titration

Détails

Ressource 1Demande d'une copie Sous embargo indéterminé.
Accès restreint UNIL
Etat: Public
Version: de l'auteur⸱e
ID Serval
serval:BIB_F6BF028607ED
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Regulatory properties of pyridine-nucleotide transhydrogenase from pseudomonas-aeruginosa. Kinetic studies and fluorescence titration
Périodique
Biochemistry
Auteur⸱e⸱s
Widmer F., Kaplan N.O.
ISSN
0006-2960
Statut éditorial
Publié
Date de publication
1976
Peer-reviewed
Oui
Volume
15
Numéro
21
Pages
4693-4699
Langue
anglais
Résumé
Mechanisms involved in the action of the pyridine nucleotide transhydrogenase from Pseudomonas aeruginosa (EC 1.6.1.1) have been investigated by means of kinetic studies and fluorescence titration. Our results, as well as those from previous investigations, suggest that the allosteric MWC model (Monod, J., Wyman, J., and Changeux, J. P. (1965), J. Mol. Biol. 12, 88-118) may be used as a first step for the explanation of the properties of the transhydrogenase. The basic reaction of the enzyme is the oxidation of reduced triphosphopyridine nucleotide (TPNH) by diphosphopyridine nucleotide (DPN+). In terms of the model, the functional R state is favored by TPNH, whereas the product triphosphopyridine nucleotide (TPN+) behaves as an allosteric inhibitor, and is therefore assumed to favor the nonfunctional T state. To a slight extent, the T state is also favored by inorganic phosphate. On the other hand, adenosine 2'-monophosphate and several other 2'-phosphate nucleotides function as activators, and hence are presumed to shift the allosteric equilibrium toward the R state. The studies in this paper suggest a specific regulatory site for the transhydrogenase.
Mots-clé
Adenosine Monophosphate/pharmacology, Kinetics, NAD/analogs & derivatives, NADH, NADPH Oxidoreductases/*metabolism, NADP/pharmacology, Pseudomonas aeruginosa/*enzymology, Spectrometry, Fluorescence
Pubmed
Web of science
Création de la notice
13/08/2015 7:53
Dernière modification de la notice
20/08/2019 16:23
Données d'usage