Structure of ethylphosphorylated Butyrylcholinesterase.
Carboxylesterase, type B is a family of evolutionarily related proteins.
Higher eukaryotes have many distinct esterases. The different types include those that act on carboxylic esters (EC 3.1.1). Carboxyl-esterases have been classified into three categories (A, B and C) on the basis of differential patterns of inhibition by organophosphates. The sequence of a number of type-B carboxylesterases indicates that the majority are evolutionarily related. As is the case for lipases and serine proteases, the catalytic apparatus of esterases involves three residues (catalytic triad): a serine, a glutamate or aspartate and a histidine. This family belongs to the superfamily of proteins with the Alpha/beta hydrolase fold.
Human genes that encode proteins containing the carboxylesterase domain include:
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