Self-Assembly of Membrane Proteins

Laboratory Directed Research and Development (LDRD)

Berend Smit, Ting Xu, co-PIs

Proteins or peptides embedded in membranes have an interesting collective behavior. For example, clustering of proteins is seen as an important factor in membrane-protein-related diseases like Alzheimer’s and Creutzfeldt-Jakob. Some organisms, as a defense against bacteria, use anti-microbial peptides that cluster in the cell membrane of a bacteria resulting in cell lysis

Finally, membrane proteins can be used as building blocks for novel materials. In the mosaic model of membranes, embedded proteins or peptides are seen as isolated molecules in a fluid. Recently, it has become clear that these molecules organize in clusters and that this may affect function and signaling. Yet the nature and structure of these clusters is as of yet poorly
understood.

The purpose of this project is to obtain a better understanding of the collective behavior of
trans-membrane proteins, as mediated by the lipid bilayer itself. With this aim we will further
develop a mesoscopic simulation model, using dissipative particle dynamics. This model will
allow us to systematically investigate, using molecular simulations, how these membrane-mediated
protein-protein interactions depend on the molecular structure of the lipid bilayer constituents.