1. Cellular Communication Laboratory, Osnabrück University, 49076 Osnabrück, Germany
2. Center of Cellular Nanoanalytic Osnabrück (CellNanOs), Osnabrück University, 49076 Osnabrück, Germany
3. Biochemistry section, Osnabrück University, 49076 Osnabrück, Germany
4. Molecular Membrane Biology section, Department of Biology/Chemistry, Osnabrück University, 49076 Osnabrück, Germany