Esterase horse liver

The enzymes used by these workers were cholinesterase, prepared from horse serum, and horse-liver esterase. Parallel experiments were carried out with twice crystallized ovalbumin, and with an aged, dialysed specimen of horse serum with negligible esterase activity. 

E. Guibe-Jampel, G. Rousseau, L. Blanco, Enzymatic Resolution of Racemic Bicyclic Lactones by Horse Liver Esterase , Tetrahedron Lett. 1989, 30, 67-68. 

ROH, horse liver esterase, solid support (enantioselective)... 

Table 11.1-5. Pig liver esterase-catalyzed enantiomer-differentiating hydrolysis of racemic carboxylic acid esters and lactones in aqueous solution (HLE horse liver esterase).

A large number of mono- and bicyclic lactones (73-91) have been obtained by using pig liver esterase in combination with horse liver esterase for the enantiomer-differentiating hydrolysis of the corresponding racemic lactones. Interestingly, in the series of methyl-substituted lactones (85-89), both enzymes show toward the seven-membered lactone (86) the opposite enantiomer selectivity as compared to the other lactones. 

Horse-serum cholinesterase Aged dialysed horse serum Ovalbumin Horse-liver esterase Heat-treated liver esterase Aged dialysed horse serum Ovalbumin... 

In contrast to the large number of readily available microbial lipases, less than a dozen of true esterases - such as pig and horse liver esterases (PLE [166, 167] and HLE, respectively) - have been used to perform the bulk of the large number of highly selective hydrolyses of carboxylic esters. Thus, the use of a different esterase is not easy in cases where the reaction proceeds with insufficient selectivity with a standard enzyme such as PLE. 

Burch, J. Purification and properties of horse-liver esterase. Biochem. J. 1954,58,415-426. 

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