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Updated: Aug 18, 2026

High-Throughput Measurement and Classification of Organic P in Environmental Samples
Published on: June 8, 2011
Differentiation of esterases reacting with organophosphorus compounds
E Reiner1, E Pavković, Z Radić
1Institute for Medical Research and Occupational Health, University of Zagreb, Croatia.
Abstract:
The hydrolysis of paraoxon (POX), phenylacetate (PA) and beta-naphthylacetate (BNA) was studied in human serum. Based upon correlations between enzyme activities, upon reversible inhibition by EDTA and upon progressive inhibition by iso-OMPA, tabun, eserine and bis-4 nitrophenylphosphate, the following conclusions were drawn about the number and specificity of enzymes involved in the hydrolysis. Two paraxonases hydrolyse paraoxon: one sensitive and the other insensitive to EDTA. The EDTA-sensitive paraoxonase also hydrolysed BNA. The EDTA-insensitive hydrolysis of BNA and PA was attributed to a serine esterase. The EDTA-sensitive hydrolysis of PA is probably due to more than one enzyme, which might be an arylesterase and a carboxylesterase.
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