SFB 803:  Functionality Controlled by Organisation in and between Membranes

• Subject Area: Chemistry ; Biology
• Term: from 2009 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 55908123

It is the aim of the Sonderforschungsbereich (SFB) (Collaborative Research Center, CRC) to unravel the interactions between the large number of different lipids and specialized proteins in cellular membranes on the molecular level. We seek to clarify how the spatial and temporal organization of membrane components influences their function. Within this general and highly active research field, the SFB has focused on two major themes: A) Organization and function of peptides and proteins in lipid membranes and B) Molecular structures associated with membrane-membrane interactions. The expected result of the SFB is to obtain molecular pictures of how peptides and proteins in the lipid membrane as well as between two membranes form structures that are responsible for transport processes across membranes and the fusion of two lipid bilayers. The results obtained in the first two funding periods put the SFB now in an ideal position to address the questions of how peptide and protein-mediated transport of small molecules and ions across membranes is achieved and how the overall membrane organization as well as specific lipid-protein-interactions alter transport properties of peptide assemblies and proteins. The expected results will provide us with a detailed understanding of the function of non-covalent peptide assemblies and transmembrane proteins such as mechanosensitive and voltage-gated channels in the context of transport phenomena across membranes. Moreover, this part of the research program forms a bridge to the second major aim of the SFB by contributing to our understanding how transmembrane helices are involved in and facilitate membrane fusion. In this regard, the SFB aims to understand how physical mesoscopic parameters such as membrane curvature and lateral tension as well as molecular determinants such as particular lipids and the molecular structure of different SNAREs (soluble N-ethylmaleimide-sensitive-factor attachment receptors) determine and influence the energy landscape along the fusion pathway. We expect to obtain a unified picture of the fusion mechanism and to understand how regulatory proteins influence this process on the molecular level.

• DFG Programme: Collaborative Research Centres

Completed projects

• A01 - The contribution of non-covalent interactions for incorporation, organization, and dynamics of peptide helices in lipid membranes (Project Heads Diederichsen, Ulf ;  Steinem, Claudia )
• A02 - Probing membrane-peptide and membrane-protein interactions by high-field pulsed EPR spectroscopy (Project Head Bennati, Marina )
• A03 - Lipid-protein interactions underlying mechanosensitivity in K2P K+ channels (Project Head de Groot, Berend )
• A04 - Structural and dynamical studies of ß-strand-membrane proteins by liquid-/solid-state NMR spectroscopy (Project Heads Andreas, Loren ;  Griesinger, Christian ;  Lange, Adam ;  Linser, Ph.D., Rasmus )
• A05 - Tailor-made glycosphingolipids as a toolkit to visualize domain formation and lipid-protein interactions (Project Heads Steinem, Claudia ;  Werz, Daniel B. )
• A06 - Structural insights into protein-ligand-membrane interactions of the bacterial membrane protein MraY: synthesis and application of chemical probes (Project Head Ducho, Christian )
• A07 - Mechanical channel gating and on-chip protein expression for direct insertion of membrane proteins (Project Head Schmidt, Christoph Friedrich )
• A09 - Membrane binding mechanism of the peripheral membrane protein pyruvate oxidase from Escherichia coli (Project Head Tittmann, Kai )
• A10 - Quantifying diffusion and dynamics of lipids within membranes in a leaflet-dependent manner (Project Head Enderlein, Jörg )
• A11 - Lipid- and ligand-dependent structure of helical membrane proteins (Project Head Zweckstetter, Markus )
• A12 - Mechanisms and dynamics of peptide permeation across membranes probed by molecular simulations (Project Head Hub, Jochen )
• B01 - Structural aspects of membrane fusion investigated by X-ray diffraction and imaging (Project Head Salditt, Tim )
• B02 - Primary lipid vesicle fusion events: Pathways, forces, energetics (Project Head Grubmüller, Helmut )
• B03 - The role of proteins on fusion and fission: computer simulation of coarse-grained models (Project Head Müller, Marcus )
• B04 - Membrane fusion assayed by pore-spanning lipid bilayers (Project Head Steinem, Claudia )
• B05 - Construction of novel hybrid biooligomers as artificial SNAREs to dissect the mechanism of SNAREs in membrane docking and fusion (Project Heads Diederichsen, Ulf ;  Jahn, Reinhard )
• B06 - Confocal fluorescence detection of docking and fusion of single proteoliposomes - focus on a novel SNARE hybrid complex (Project Heads Jahn, Reinhard ;  Walla, Peter Jomo )
• B08 - A quantitative assessment of the role of lateral tension, curvature, and external forces in membrane fusion (Project Head Janshoff, Andreas )
• B09 - Functional analysis of membrane remodeling by epsin1 (Project Head Meinecke, Michael )
• Z01 - Central administration and project coordination of the CRC (Project Head Steinem, Claudia )
• Z02 - Statistical methods for time-varying electrophysiological data and for protein-membrane interactions (Project Head Munk, Axel )
• Ö01 - Making science visible: information, motivation and participation in formal and non-formal educational offers (Project Heads Mey, Ingo ;  Waitz, Thomas )

• Applicant Institution: Georg-August-Universität Göttingen
• Participating University: Technische Universität Braunschweig
• Participating Institution: Max-Planck-Institut für biophysikalische Chemie; (Karl-Friedrich-Bonhoeffer-Institut) (aufgelöst)
• Spokesperson: Professorin Dr. Claudia Steinem