Diisopropylphosphoric acid

Diisopropylphosphoric acid produced the greatest activity (Table 1) while diethylisopropylphosphoric acid gave approximately half the specific activity of DPA and is unstable. Since DEIP is unstable and DPA is not commercially available, we used HMPA as the modifier for preparing and characterizing semisynthetic fluorohydrolases. Furthermore, HMPA has been shown to generate activity with other proteins as well as RNase (Table 2). 

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