Detoxification of organophosphate pesticides using an immobilized phosphotriesterase fromPseudomonas diminuta

摘要: A purified phosphotriesterase was successfully immobilized onto trityl agarose in a fixed bed reactor. total of up to 9200 units enzyme activity 2.0 mL (65 micromol groups/mL agarose), where one unit is the amount required catalyze hydrolysis micromole paraoxon min. The shown behave chemically and kinetically similar free when utilized as substrate. Several organophosphate pesticides, methyl parathion, ethyl diazinon, coumaphos were also hydrolyzed by phosphotriesterase. However, all substrates exhibited an affinity for matrix. For increased solubility reduction these pesticides matrix, methanol/water mixtures utilized. effect methanol not deleterious concentrations less than 20% present. higher resulted elution from With 10-unit reactor, 1.0 mM solution completely at flow rate 45 mL/h. Kinetic parameters measured with 0.1-unit reactor substrate 22 apparent K(m) 3-4 times greater (0.1 mM) soluble enzyme. Immobilization limited maximum 40% value observed pH-rate profiles enzymes very similar. immobilization provides effective method esterase hydrolyzing thus detoxifyuing mammalian acetylcholinesterase inhinbitors.