funded by the Deutsche Forschungsgemeinschaft - DFG
1. funding period 2009-2012
2. funding period 2013-2016
Biological membranes are commonly described as two-dimensional fluid mosaics, serving as mechanical, chemical, and electrical barriers. The fluid nature and complex chemical composition of the lipid bilayer, in which a multitude of proteins are embedded as functional units, as well as its flexibility, are prerequisite for the various tasks membranes have to fulfil. Among others, these include formation and dissipation of electrochemical gradients, transport of molecules and larger cargoes, adaptation of shape, as well as fusion of membranes. Even though research in this field has a long tradition, methods for addressing the chemical complexity of biological membranes have only recently become available. Presently, rapid progress is being made in understanding how membranes are organized and how membrane organization translates into the functioning of proteins that together define the unique properties of a biological membrane. However, there is still a lot to learn about the structure and function of membrane proteins. In particular, it is becoming increasingly evident that their functional properties are strongly dictated by the lipid environment.
The Sonderforschungsbereich 803 (SFB 803) aims to elucidate basic principles underlying the complex interplay between lipids and membrane proteins in order to understand membrane processes at the molecular level. All projects primarily use tailored model membranes with defined and controllable lipid and protein compositions. With this unique approach, quantitative high-resolution (spatial and temporal) information is obtained that sheds new light on lipid and protein dynamics and the structural organization of membranes. One of our major goals is to derive general concepts for the self-organization of transmembrane peptide helices in lipid membranes as well as for the structure-function relationships of water- and ion permeating channels. Furthermore, we seek to acquire a dynamic molecular picture of membrane structures during the process of membrane fusion by unravelling the entire fusion pathway with the aim of establishing a link between molecular structures, lipid composition and mesoscopic membrane mechanics.