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

Research output: Contribution to journalResearch articleContributedpeer-review


  • Elisabeth Fischermeier - , Biotechnology Center, Department of Visceral, Thoracic and Vascular Surgery, Helmholtz-Zentrum Dresden-Rossendorf, TUD Dresden University of Technology, National Center for Tumor Diseases (NCT) Heidelberg (Author)
  • Petr Pospíšil - , Chair of Tissue Dynamics, J. Heyrovský Inst. Physical Chemistry of the A.S.C.R. v.v.i, University of Prague, Czech Academy of Sciences (Author)
  • Ahmed Sayed - , Biotechnology Center, Chair of Biomolecular Interactions, Helmholtz-Zentrum Dresden-Rossendorf, TUD Dresden University of Technology, Alikhanov Institute for Theoretical and Experimental Physics (Author)
  • Martin Hof - , J. Heyrovský Inst. Physical Chemistry of the A.S.C.R. v.v.i (Author)
  • Marc Solioz - , University of Bern (Author)
  • Karim Fahmy - , Helmholtz-Zentrum Dresden-Rossendorf (Author)


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.


Original languageEnglish
Pages (from-to)1269-1272
Number of pages4
JournalAngewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition
Issue number5
Publication statusPublished - 24 Jan 2017

External IDs

Scopus 85007324122



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