Activity-based protein profiling: an enabling technology in chemical biology research.

Activity-based protein profiling (ABPP) is one of the main driving forces in chemical biology and one of the most visible areas where organic chemistry contributes to chemical biology research. In recent years, ABPP research has gradually made the transfer from the relatively easy target enzymes (for instance serine hydrolases, cysteine and threonine proteases) toward targeting enzymes that are intrinsically more difficult to address. These include less abundant enzymes, enzymes that do not employ a nucleophilic amino acid residue in their active site and enzymes more particular with respect to their substrate. At the same time, ABPP has started to make a tangible impact on clinical research.