• Citer

Difference between the E1 and E2 conformations of gastric H+/K+-ATPase in a multilamellar lipid film system. Characterization by fluorescence and ATR-FTIR spectroscopy under a continuous buffer flow.

par Vander Stricht, D V;Raussens, Vincent ;Oberg, KEITH ;Ruysschaert, Jean Marie ;Goormaghtigh, Erik
Référence European journal of biochemistry / FEBS, 268, 10, page (2873-2880)
Publication Publié, 2001-05

Article révisé par les pairs

• Accès en ligne
• Détails
• Contenu
• Statistiques

Résumé :

A liquid flow cell was used for an attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) study of conformational changes taking place in the gastric H+/K+-ATPase. Shifting from E1 to E2 form is induced by replacing Na+ by K+ ions. Introducing ions through a flow passing over a protein multilayer film induced the conformational change without cell manipulations. Measurement sensitivity was thereby improved by about one order of magnitude. The detection threshold allowed the possibility to detect a change affecting five amino acids out of the 1324 that compose the H+/K+-ATPase molecule. It appeared that fewer than five amino-acid residues undergo a conformational change upon replacing Na+ by K+ ions in the medium. Evidence that conformational changes occur in an identical system was brought by monitoring the fluorescence of fluorescein isothiocyanate-labeled H+/K+-ATPase in similar conditions. Our data suggest that essentially the tertiary structure of the protein is modified.