Activity-based protein profiling: Chemical approaches for functional proteomics

ORGN 229

Benjamin F. Cravatt, Departments of Chemistry and Cell Biology, Departments of Chemistry and Cell Biology, Skaggs Institute for Chemical Biology and Scripps Research Institute, La Jolla, CA 92037
The field of proteomics aims to characterize dynamics in protein function on a global scale. However, several classes of enzymes are regulated by posttranslational mechanisms, limiting the utility of conventional proteomics techniques for the characterization of these proteins. Our research group has initiated a program aimed at generating chemical probes that interrogate the state of enzyme active sites in whole proteomes, thereby facilitating the simultaneous activity-based profiling of many enzymes in samples of high complexity. Progress towards the generation and utilization of active site-directed chemical probes for the proteomic characterization of several enzyme classes will be described. These enzyme classes fall into two general categories: 1) enzymes for which active site-directed affinity agents have been well-defined, and 2) enzymes for which active site-directed affinity agents have been lacking. The application of activity-based protein profiling to the functional characterization of enzyme activities that vary in human cancer specimens will be highlighted, as will be the use of this strategy as a screen to discover potent and selective reversible enzyme inhibitors.