Enzymatic hydrolysis of Russian-VX by organophosphorus hydrolase

The Russian-VX (R-VX) is the priniple V-type nerve agent in the chemical warfare (CW) arsenal of the Former Soviet Union. We here report the enzymatic hydrolysis of the P-S bond of Russian-VX by organophos phorus hydrolase (OPH) from Pseudomonas diminuta. While the Michaelis constant, K-m for R-VX (474 mu M), was similar to that for VX (434 mu M), the V-max for R-VX (2.1 mu moles/mg/min) was about four-fold higher compared to that for VX (0.56 mu moles/mg/min). A 50% inhibition in the rate of the enzymatic hydrolysis of R-VX was observed in the presence of 0.5% ethanol, isoamylalcohol, or isopropanol The presence of acetonitrile, diethylene glycol, or methanol had marginal effects. These results comprise the first demonstration of enzymatic detoxification of R-VX. (C) 1997 Academic Press.