HA-Ubiquitin-Vinyl Methyl Ester

Ubiquitin is a small (8.5 kDa) regulatory protein that has been found in almost all tissues of eukaryotic organisms. Ubiquitination can affect proteins in many ways; it can signal for their degradation via the proteasome, alter their cellular location, affect their activity, and promote or prevent protein interactions. Removal of ubiquitin from a substrate protein occurs via deconjugating enzymes, of which there are nearly 100 known enzymes with various linkage specificities. This product consists of a full-length human, mature ubiquitin polypeptide (amino acids 1-76), expressed in E.coli with a c-terminal warhead (Vinyl Methyl Sulfone) and an N-terminal HA-Tag. HA-Ubiquitin-Vinyl Methyl-Sulfone is a potent, irreversible, and specific inhibitor of deubiquitinating enzymes (DUBs) based on a C-terminal electrophilic Vinyl Sulfone group. It targets three of the four major DUB families: UCH (Ubiquitin c-terminal hydrolases), USP (Ubiquitin Specific Proteases), OTU (Ovarian Tumor Proteases), and MJD (Machado-Josephin domain proteases) while JAMM metalloproteases are not inhibited. HA-Ub-VME can be used for activity profiling experiments and using the HA-Tag conveniently for Immunoprecipitations in search for new or novel enzymes reacting with the c-terminal warhead. Reaction conditions will need to be optimized for each application. We recommend an initial HA-Ubiquitin-VME concentration of 1-5 μM.