title: ATP-binding is stabilized by a stacking interaction within the binding site of Na+/K+ -ATPase.
abstract: Site-directed mutagenesis was applied to modify phenylalanines (Phe(475)Trp, Phe(548)Tyr, and both) to generate mutants on the basis of molecular modeling of the ATP-binding domain of Na(+)/K(+)-ATPase, in order to characterize the forces that stabilize ATP in its binding pocket. Each of the mutants was examined by Raman difference spectroscopy, i.e., as a difference between the spectrum of the domain with and without bound ATP. It was shown that Phe(475) plays a key role in stabilizing ATP-binding by a stacking interaction. Phe(548) co-stabilizes ATP on the opposite site of the binding pocket and its type of interaction with ATP-binding differs from that of Phe(475).
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic, Vídenská 1083, CZ-14220 4, Prague, Czech Republic.
authors.forename: Katerina
authors.initials: K
authors.lastname: Hofbauerová
authors.forename: Vladimír
authors.initials: V
authors.lastname: Kopecký
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Ettrich
authors.forename: Martin
authors.initials: M
authors.lastname: Kubala
authors.forename: Jan
authors.initials: J
authors.lastname: Teisinger
authors.forename: Evzen
authors.initials: E
authors.lastname: Amler
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002851:Chromatography, High Pressure Liquid; D051379:Mice; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D010649:Phenylalanine / Q000737:chemistry; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry* / Q000378:metabolism; D013059:Spectrum Analysis, Raman
chemical_list: D010649:Phenylalanine; D000255:Adenosine Triphosphate; D000254:Sodium-Potassium-Exchanging ATPase