The inhibition of chymotrypsin by diethyl p-nitrophenyl phosphate

The alkyl fluorophosphonates were first shown in 1940 (Adrian, Feldberg & Kilby, 1947) to be very powerful inhibitors of cholinesterase, and for a time they were thought to be quite specific for this enzyme.Later, other esterases, such as human milk lipase and liver esterase (Webb, 1948) and citrus acetylesterase (Jansen, Nutting & Balls, 1947) were * The non-protein nitrogen was less than 0-1 %.Chymotrypsin in sample (%)