D-tagatose-3-epimerase （DTE） catalyzes the epimerization of various ketohexoses at C-3 position, and commonly catalyzes the reversible interconversion of D-fructose to D-psicose, which is a novel useful low-calorie sweetener with many beneficial effects. A new gene, encoding the hypothetical protein with locus ZP 02432283 from the Clostridium scindens ATCC 35704 was cloned and over-expressed in E. coli. BL21 （DE3）. The recombinant protein was purified to electrophoretical homogeneity by affinity chromatography using Chelating Sepharose Fast Flow resin and analyzed by SDS-PAGE, showing approximately 31 ku characteristic protein. The recombinant enzyme activity was determined by measuring D-sorbose formed using D-tagatose and D-psicose formed using D-fructose as a substrate, the bioconversion rate reached 8.6% and 27.9% , respectively.%D-阿洛酮糖作为一种新型低热量功能性甜味剂，可以通过D-塔格糖-3-差向异构酶家族，以D-果糖为底物C-3位异构化得到。一个新的来源于微生物Clostridium scindens ATCC 35704中ZP 0243228的D-塔格糖-3-差向异构酶基因（CS-DTE），通过克隆并成功导入E．coli BL21（DE3）中，构建了基因重组菌，诱导目的重组基因过量表达；经亲和层析纯化的重组蛋白样品进行SDS—PAGE分析，在约31ku处出现显著的特征蛋白条带；通过对其活性检测表明，该重组酶分别以D-塔格糖和D-果糖为底物，可以生成D-山梨糖和D-阿洛酮糖，转化率分别为8．6％和27．9％。
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