Researchers at the Ruhr Universitt Bochum have developed a new method for attaching proteins to the surface of germanium crystals for the first time also membrane proteins. This enables time-resolved tracking of the interactions between molecules using infrared spectroscopy in a way that is accurate down to atomic resolution. The method is applied in the EU project "Kinetics for Drug Discovery, K4DD", in which scientists explore the interplay of drugs and their interaction partners. With the new technology, the researchers can also study so-called G-protein-coupled receptors, which are the site of action for many drugs. The team of Prof. Dr. Klaus Gerwert, PD Dr. Carsten Ktting and Jonas Schartner from the Chair of Biophysics reports in the "Journal of the American Chemical Society".
Attaching proteins to germanium using electron pair bonds
Using infrared (IR) difference spectroscopy, researchers analyse dynamic processes in proteins. In an earlier study, Bochum's biophysicists already succeeded in binding proteins to germanium surfaces using lipids, thus making them accessible to IR spectroscopy (as reported in September 2012: http://aktuell.ruhr-uni-bochum.de/pm2012/pm00284.html.de). For this, the researchers shine infrared light into the germanium crystal, which is multiply reflected at its boundary surfaces. Part of the light leaves the crystal and thus reaches the proteins bound to the surface. Previously, the researchers used hydrophilic interactions between the crystal and lipid i.e. interactions between polar groups of the molecules for the bonding. Now they coupled the proteins via an electron pair bond to the germanium. This kind of bond is more stable and works both for soluble and membrane proteins. "Membrane proteins need a kind of soap as an outer shell, a detergent, which washes off a lipid layer. In contrast, our newly deve
|Contact: Dr. Carsten Ktting|