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.