Discovery of multiple organofluorophosphate hydrolyzing activities in the protozoan Tetrahymena thermophila.

摘要: Recently it has been found that homogenates of Tetrahymena thermophila can hydrolyze the potent acetylcholinesterase inhibitors O,O-diisopropylphosphofluoridate (DFP) and O-1,2,2-trimethylpropylmethylphosphonofluoridate (soman). Upon purification DFP hydrolyzing activity 10-fold had noted soman increased only 2-3 fold. Treatment with manganous ion comparison hydrolysis rates homogenate indicated a mixture squid-type Mazur-type DFPases may be present. Subsequent enzymatic activities within Tetrahymena-homogenate demonstrated there are at least five functioning proteins molecular weights 67,000 to 96,000. None directly homologous in hog kidney or squid. The designated DFPase-1 through DFPase-5. A hypothesis is presented functions normal metabolism organophosphates naturally synthesized by T. thermophila.