Structure and molecular mechanisms of membrane transport proteins
Research report (imported) 2003 - Max Planck Institute of Biophysics
The Department of Structural Biology at the Max Planck Institute of Biophysics focuses on the structure and molecular mechanisms of membrane transport proteins. The structures of membrane proteins purified from natural sources or expressed in suitable host organisms are determined by electron microscopy or x-ray crystallography. The 2.5Å x-ray structure of the plant light-harvesting complex LHC-II reveals the mechanism of photoprotection and a likely pathway for dissipating excess solar energy. A three-dimensional map of a neuronal ion channel, determined by single-particle electron microscopy, shows the position of the alpha and beta subunits in the functional assembly. The 8Å map of the bacterial protein translocase SecYEG in the membrane shows how the structure adapts to the early steps of protein translocation. Structural studies of the protein translocase from outer and inner membranes of mitochondria reveal a twin pore. Two-dimensional crystals of various secondary transporters show different arrangements of membrane-spanning helices, indicative of different transport mechanisms.