Exposure of bovine pulmonary-arterial endothelial cells to the oxidant lipid t-butyl hydroperoxide (t-Bu-OOH) increases cell-membrane-associated phospholipase A2 (PLA2) activity and stimulates arachidonic acid (AA) release. To test the hypothesis that a membrane-associated serine esterase plays an important role in activating PLA2, the present study was undertaken. In addition to increasing PLA...

The specificity of the amidase and kininogenase methods for determining rat urinary kallikrein was studied. Male and female rat urine was employed. Esterase A1, A2 and kallikrein were separated by DEAE-Sephadex A-50 chromatography. Esterase A1 showed no amidase activity towards the substrate H-D-Val-Leu-Arg-p-nitroanilide. In contrast, esterase A2 and kallikrein attacked the substrate, and the ...

Hevea brasiliensis hydroxynitrile lyase (HbHNL) and salicylic acid binding protein 2 (SABP2, an esterase) share 45% amino acid sequence identity, the same protein fold, and even the same catalytic triad of Ser-His-Asp. However, they catalyze different reactions: cleavage of hydroxynitriles and hydrolysis of esters, respectively. To understand how other active site differences in the two enzymes...

Certain organophosphorus esters such as diisopropylfluorophosphate (DFP) cause delayed neuropathy by inhibition of neuropathy target esterase (NTE) keeping neuron in normal function. In this study, effects of neurobion alone and in combination with dexamethasone on DFP–induced delayed neuropathy were evaluated. Thirty-five mice were divided to five groups that each group consists 7 mice. Except...

Cholesterol esterase of pancreatic juice origin and acyl coenzyme A:cholesterol acyltransferase, both associated with the intestinal mucosa, are implicated in the extensive esterification of exogenous cholesterol during absorption. To assess the role of each enzyme, [4-14C]cholesterol absorption into mesenteric lymph of rats with normal mucosal levels of both esterification enzymes was compared...

Interest in the distribution of choline esterase activity between the cells and plasma dates back a dozen years or more, but relatively little investigation has been carried out. In 1928 Galehr and Plattner (1), using a biological assay method, found that there was more choline esterase activity in human blood cells than in serum, and their finding was confirmed by Matthes (2) in 1930. The este...