Carboxylesterase 3 (CES3)

Carboxylesterase 3 (CES3) is a member of the human carboxylesterase enzyme family, structurally related to CES1 and CES2, and classified as a serine hydrolase within the alpha/beta hydrolase fold superfamily[2][3]. CES3 is expressed in the liver, intestine, and other tissues, where it catalyzes the hydrolysis of a wide range of endogenous and exogenous esters and amides for the purposes of detoxification and metabolic clearance[1][2]. Carboxylesterases play essential roles in drug metabolism, influencing both the activation (for prodrugs) and inactivation (for toxicants) of numerous compounds[2]. While CES3 shares many molecular properties and functions with CES1 and CES2, it is less studied; most current understanding is extrapolated from its sequence similarity and predicted structural features[2][3]. The enzyme employs a conserved catalytic triad (serine, glutamate, and histidine) in its active site to perform hydrolysis, and mutations in this triad abolish enzyme activity[2][3]. CES3 is likely important in the biotransformation of drugs containing ester linkages and may influence pharmacokinetic variability among individuals[2].

Other names

CES3human carboxylesterase 3liver carboxylesterase 3carboxylesterase 3Aliver carboxylesterase-like protein

Hydrolytic cleavage of ester/amide bonds (for prodrug activation or detoxification); Transesterification (less common, but possible, as seen for CES1 in related literature)