Dipolar Relaxation Dynamics at the Active Site of an ATPase Regulated by Membrane Lateral Pressure

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

Abstract

The active transport of ions across biological membranes requires their hydration shell to interact with the interior of membrane proteins. However, the influence of the external lipid phase on internal dielectric dynamics is hard to access by experiment. Using the octahelical transmembrane architecture of the copper-transporting P1B -type ATPase from Legionella pneumophila as a model structure, we have established the site-specific labeling of internal cysteines with a polarity-sensitive fluorophore. This enabled dipolar relaxation studies in a solubilized form of the protein and in its lipid-embedded state in nanodiscs. Time-dependent fluorescence shifts revealed the site-specific hydration and dipole mobility around the conserved ion-binding motif. The spatial distribution of both features is shaped significantly and independently of each other by membrane lateral pressure.

Details

OriginalspracheEnglisch
Seiten (von - bis)1269-1272
Seitenumfang4
FachzeitschriftAngewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition
Jahrgang56
Ausgabenummer5
PublikationsstatusVeröffentlicht - 24 Jan. 2017
Peer-Review-StatusJa

Externe IDs

Scopus 85007324122

Schlagworte

Schlagwörter

  • 2-Naphthylamine/analogs & derivatives, Bacterial Proteins/chemistry, Catalytic Domain, Circular Dichroism, Cysteine/chemistry, Fluorescent Dyes/chemistry, Legionella pneumophila/enzymology, Nanostructures/chemistry, Protein Structure, Secondary