The four most important non-specific carboxylesterases from rat liver were assayed for their ability to hydrolyse retinyl esters. Only the esterases with pI 6.2 and 6.4 (= esterase ES-4) are able to hydrolyse retinyl palmitate. Their specific activities strongly depend on the emulsifier used (maximum rate: 440 nmol of retinol liberated/h per mg of esterase). Beside retinyl palmitate, these este...

Esterases are involved in the susceptibility or resistance of organisms to organophosphate pesticides. We have examined the action of parathion on the marine dinoflagellates Crypthecodinium cohnii and Prorocentrum micans by looking at their esterases. One-dimensional gel electrophoresis, immunoblotting and cytochemistry plus image analysis were used to characterize the nature and distribution o...

Glucuronoyl esterases are enzymes involved in microbial plant cell-wall degradation. In this study we purified and characterized two recombinant Phanerochaete chrysosporium glucuronoyl esterases, PcGE1 and PcGE2. The catalytic activity of these and previously described glucuronoyl esterases was investigated on new synthetic substrates, methyl esters of uronic acids and their glycosides, prepare...

Germinating seeds of Tamarindus indica synthesizes various enzymes which are required for the degradation of seed reserves such as xyloglucans, fatty acid esters and proteins. Among these, esterases, belonging to a group of hydrolytic enzymes catalyze the hydrolysis of various types of esters. They play an important role in cell expansion as well as detoxification of xenobiotics and many agroch...

The activity of esterase secreted by conidia of wheat powdery mildew fungus, Blumeria graminis f. sp. tritici, was assayed using indoxyl acetate hydrolysis, which generates indigo blue crystals. Mature, ungerminated, and germinating conidia secrete esterase(s) on artificial media and on plant leaf surfaces. The activity of these esterases was inhibited by diisopropyl fluorophosphate, which is s...

NTEREST in searching for genetic variation in esterases was stimulated by I the work of MARKERT and HUNTER (1959) who observed that electrophoretic differences between the esterases of various tissues in mice can be readily demonstrated in starch gels by applying appropriate histochemical staining techniques. Since then, genetic variation in esterases has been reported in studies of maize endos...