(A) Substrate specificity assay. Rates of hydrolysis were measured with fatty acids of various acyl chain lengths, from pNP-acetate to pNP-palmitate. The highest level of activity, observed with the C8 substrate, was taken as 100%. (B) Effects of inhibitors on recombinant esterase activity. Different concentrations of DEPC, PMSF, PAO, and PGO were incubated with the enzyme for 30 min at 37°C. The reaction was stopped by chilling on ice, and aliquots were assayed by the standard method.