Monitoring of phosphatase and kinase activity using P NMR spectroscopy

Traditionally, enzymatic assays require the addition of labels or exogenous supplementation sources. Phosphorus-31 nuclear magnetic resonance ( 31 P NMR) spectroscopy has proven to be a powerful and reliable tool, but it is scarcely employed to evaluate enzymatic activity. Herein, we provide a versatile method to directly characterize phosphatase and kinase activities by exploiting the apparently differential 31 P NMR shifts between substrates and products, without requiring tags or additional reagents. The utility of this method for inhibitor identification is also presented. We provide a new method for the direct identification of enzyme activity based on signal changes of phosphorus-containing small molecules in 31 P NMR spectroscopy.