Physical Sciences and Mathematics Commons^™

Identification Of Inhibitors That Target Dual-Specificity Phosphatase 5 Provide New Insights Into The Binding Requirements For The Two Phosphate Pockets, Terrence S. Neumann, Elise A. Span, Kelsey S. Kalous, Robert D. Bongard, Adam Gastonguay, Michael A. Lepley, Raman G. Kutty, Jaladhi Nayak, Chris Bohl, Rachel G. Lange, Majher I. Sarker, Marat R. Talipov, Rajendra Rathore, Ramani Ramchandran, Daniel S. Sem

Chemistry Faculty Research and Publications

Background: Dual-specificity phosphatase-5 (DUSP5) plays a central role in vascular development and disease. We present a p-nitrophenol phosphate (pNPP) based enzymatic assay to screen for inhibitors of the phosphatase domain of DUSP5.

Methods: pNPP is a mimic of the phosphorylated tyrosine on the ERK2 substrate (pERK2) and binds the DUSP5 phosphatase domain with a Km of 7.6 ± 0.4 mM. Docking followed by inhibitor verification using the pNPP assay identified a series of polysulfonated aromatic inhibitors that occupy the DUSP5 active site in the region that is likely occupied by the dual-phosphorylated ERK2 substrate tripeptide (pThr-Glu-pTyr). Secondary assays …