Qbjective:The Ces1f cDNA coding carboxylesterase was cloned from Mouse liver.Methods:The Ces1f cDNA was amplified from mouse liver by RT-PCR, and inserted in pUCm-T to determine the DNA sequence. the Ces1f cDNA was subcloned into expression vector pET-32a to construct the recombinant expression vector pET-32a-Ces1f, and transformed into the host strain E. coli BL21 (DE3) . Recombinant CES expression was induced by IPTG, and purified by Ni-NTA affinity chromatography. SDS-PAGE method were used to identify the expression and its speci-fied enzyme activity were assayed.Results:A 77kDa recombinant CES was successfully expressed, The specified en-zyme activity of purified enzyme were 55.37U/mg. HPLC detection showed Carbaryl、carbofuran and Metaphos were degraded by the recombinant.Conclusion:A method for expression and purification of mouse recombinant CES was suc-cessfully established.The method laid the foundation for the degradation of pesticide residues in the environment.%从小鼠肝脏中克隆羧酸酯酶（CES）基因家族成员Ces1f的cDNA，在大肠杆菌中表达，并验证重组酶对农药的作用。采用RT-PCR克隆Ces1f cDNA，与pUCm-T载体连接测序后，亚克隆至表达载体pET-32a，构建重组表达质粒pET-32a-Ces1f，转化到宿主菌BL21（DE3）后经IPTG诱导表达，经SDS-PAGE鉴定，采用Ni柱对表达产物进行纯化并测重组CES的酶比活，利用HPLC验证重组酶对不同农药的作用。结果显示：成功获得纯化的77kDa的重组CES蛋白，其酶液的比活为55.37U/mg，HPLC检测发现重组CES对西维因、呋喃丹及甲基对硫磷等具有降解作用。成功表达重组CES，其对农药具有降解作用，为环境中农药残留的降解奠定了基础。
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