A Functional Proteomic Strategy to Discover Inhibitors for Uncharacterized Serine Hydrolases

Hydrolytic enzymes constitute one of the largest and most diverse protein classes in Nature and play key roles in nearly all physiological and pathological processes. The mammalian serine hydrolase superfamily contains a remarkable number of uncharacterized members, with at least 40-50% of these enzymes lacking experimentally verified endogenous substrates and products. Assignment of metabolic and cellular functions to these enzymes requires the development of pharmacological tools to selectively perturb their activity. We describe herein a functional proteomic strategy to systematically develop potent and selective inhibitors for uncharacterized serine hydrolases, and its application to create a highly potent and selective inhibitor of the brain enriched enzyme alpha/beta-hydrolase-6, monoacylglycerol lipase and alpha/beta-hydrolase-11. We also comprehensively profiled serine hydrolase activities in adipocyte cell lines, identified WWL113 as a selective and potent inhibitor for carboxylesterase3 in 10T1/2 cell line and demonstrated its potential application in metabolic syndrome. We anticipate that the methods described herein will facilitate the development of selective chemical probes to annotate the metabolic and (patho)physiological functions of many of the uncharacterized serine hydrolases that currently populate eukaryotic and prokaryotic proteomes.