Bio-orthogonally tagged activity-based probes forproteomics of deubiquitinating enzymes
A recent paper in Nature Communications describes a collaborative effort between scientists at UbiQ, Genentech, Boston Biochem (Bio-Techne) and Stanford University (1). Here a reactive-site-centric chemoproteomics protocol is presented which allows evaluating activity and probe reactivity of deubiquitinating enzymes (DUBs, also termed deubiquitylases). The chemoproteomics protocol makes use of a new type of bio-orthogonally tagged activity-based probe (ABP) and sequential on-bead digestions to enhance the identification of probe-labeling sites on DUBs (Figure 1). Ultimately, ZUFSP (ZUP1) was identified as a previously unannotated DUB with high selectivity toward cleaving K63-linked ubiquitin chains (3-5).