Discovery of Cell-Type-Specific and Disease-Related Enzymatic Activity Changes via Global Evaluation of Peptide Metabolism.

Cellular homeostasis is maintained by a complex network of reactions catalyzed by enormous numbers of enzymatic activities (the enzymome), which serve to determine the phenotypes of cells. Here, we focused on the enzymomics of proteases and peptidases because these enzymes are an important class of disease-related proteins. We describe a system that (A) simultaneously evaluates metabolic activities of peptides using a series of exogenous peptide substrates and (B) identifies the enzymes that metabolize the specified peptide substrate with high throughput.

Identification of tissue-restricted bioreaction suitable for in vivo targeting by fluorescent substrate library-based enzyme discovery.

Tissue-restricted bioreactions can be utilized to design chemical-biological tools and prodrugs. We have developed a fluorescent-substrate-library-based enzyme discovery approach to screen tissue extracts for enzymatic activities of interest. Assay-positive candidate proteins were identified by diced electrophoresis gel assay followed by peptide mass fingerprinting.