UbiQ-124

UbiQ-124 (Dha= dehydroalanine) is a new and first of its kind activity based probe for the SUMO ligation pathway. It is based on the SUMO3 sequence in which the C-terminal Gly has been replaced by a dehydroalanine residue. The N-terminus is labeled with the His10 affinity tag and the SUMO3 sequence contains a K11R (to prevent polysumoylation) and C47S mutation. UbiQ-124 is processed in a native manner by SUMO E1, E2 and E3 ligases and during this process it forms an electrophilic intermediate that can react with the active site Cys residue of the E1, E2 and E3 enzymes, thereby creating a covalent bond (see figure ).