Structural Biology of Membrane Transporters
Proteins involved in substrate translocation across biological membranes are divers and the variety nature evolved to control substrate flux is absolutely fascinating. Generally spoken, there are just two classes of proteins, transporters and channels, responsible for the controlled substrate translocation across membranes. However, both classes already differ drastically in their mode of action: While ion channels enable a selective, dissipative ion flux down an electrochemical gradient, ion transporters work in an energy-dependent manner allowing the accumulation of ions against a gradient. Additionally, the variety of different mechanisms and strategies for substrate translocation within both classes is huge and far from being completely understood.
Our research focuses on the structure and function of ion transporters and channels. In particular, our goal is to understand how bacterial K(+) uptake systems of the Ktr/Trk/HKT family are translocating potassium ions across the plasma membrane. By use of x-ray crystallography, EPR spectroscopy, electrophysiology and biochemical methods we are endeavoring to unravel the physiology and the mechanisms underlying K(+) translocation of these proteins.