Substrate Binding Studies with the 20S Proteasome

proteasome side view The 20S-proteasome is a large barrel shaped protein complex, degrading cytosolic proteins into oligopeptides. Most of these fragments will be further degraded by other proteases, a small fraction however is presented at the cell surface by the MHC-I complex. Cytotoxic T-cells, will kill each cell presenting unknown structures. Proteolysis takes place inside the barrel. The substrate enters the proteasome through narrow pores at both ends and travels to the active sites in a central cavity where the substrate is cleaved into a variety of fragments. Our goal is to shed light on the binding mechanism and the sequence speciticity of cleavage using MD simulations.

Another project concerns the general prediction of cleavage probabilities from limited experimental datasets.