Collaborative Research Centre 803

Functionality controlled by organization in and between membranes

Since many years, structure, function and dynamics of biological membranes have fascinated scientists. Membranes are essential for life as they are the only means by which closed compartments can be generated that shield the biochemical reactions of a living cell from the environment. Although research on membranes has a long tradition, there are still major white spots in our picture as to how membranes are organized and in particular how the organization translates into the functioning of proteins that together define the unique properties of a biological membrane. The concept of the Collaborative Research Centre (CRC) is guided by the idea that molecular and quantitative information about the interplay between membrane lipids and proteins is crucial for understanding essential properties and functioning of membranes at the molecular level. It will be our long term goal to be able to predict protein functionalities and extract common structural and functional motifs on the protein and on the lipid side, respectively, paving the way to understand the dynamics of membrane processes. In pursuing this goal, we primarily take a “reductionist’s” bottom up approach in order to reduce the complexity of a native biological membrane. The common basis of all theoretical and experimental projects is the use of artificial membranes with a defined chemical composition. The groups (chemists, mathematicians, and physicists) participating in the CRC are united by a strong interest to probe deeper into the molecular details of peptide-lipid interactions and into the structure of membrane contact zones, while still maintaining a sufficient diversity in both structure and function of the peptides and proteins under study.

The projects in part A deal with the question of how bilayer-forming membrane lipids influence peptide and protein conformations, their assemblies and organization in a membrane, and how these interactions influence the function of the proteins. The projects in part B deal with the question how proteins that influence membrane structure interact with lipids and how they affect the change in the bilayer organization, with particular emphasis on membrane fusion.