Esterase-30 (ES-30) of the house mouse: Biochemical characterization and genetics of a new carboxylesterase isozyme linked to cluster-2 loci on chromosome 8

Abstract

A new carboxylesterase isozyme (EC 3.1.1.1), designated ES-30, is described in mouse liver. Two phenotypes were distinguished, ES-30A, a possible null type, was found in SPE/Pas and in other lines derived from Mus spretus, and ES-30B was found in BALB/cJ and other laboratory inbred strains. ES-30B is characterized by a distinct electrophoretic band when stained using 5-bromoindoxyl acetate as the substrate. After isolation and purification from other esterases by ion-exchange chromatography and molecular sieving, the molecular mass was estimated by two independent methods to be 62 and 64 kDa, respectively. The activity of ES-30B is higher in adult males than in females and can be stimulated in vivo by testosterone. The distribution of phenotypes on the progeny of a backcross series suggests a separate locus, Es-30, with the allele a for absence and b for presence of the isozyme. Locus Es-30 is shown to be closely linked to Es-2 and to Es-7 of cluster-2 on chromosome 8. The gene order Es-9--Got-2--(Es-2, Es-7, Es-30) is suggested.

Purification and Cloning of a Broad Substrate Specificity Human Liver Carboxylesterase That Catalyzes the Hydrolysis of Cocaine and Heroin

“…The cDNA sequences for all 4 rat hydrolases have been published and confirm the suggestion of Mentlein et al (11) that there are many carboxylesterases expressed in rat liver. Multiple carboxylesterase isozymes also were identified in mouse liver that are encoded by two gene clusters on chromosome 8 (12). Less is known about the multiplicity and genetics of carboxylesterases in rabbit, hamster, pig, or human tissues.…”