Purification and Characterization of D-psicose 3 Epimerase (DPEase) From Escherichia coli BL21 (DE3) pET21b dpe.

ABSTRACT

BACKGROUND AND OBJECTIVE: The DPEase enzyme from Agrobacterium tumefaciens is more efficient and has a high activity in D-fructose. The dpe gene has been successfully cloned to Escherichia coli BL21 (DE3) pET-21b dpe but the enzyme has not been purified and its character is unknown. The intent of this study was to purify and assign of DPEase enzyme by recombinant E. coli. MATERIALS AND METHODS: The enzyme was clarified by affinity chromatography and then characterized by following pH, temperature, co-factor parameters. Analysis of molecular weight proteins was done by SDS-PAGE. RESULTS: Through purification, the purified DPEase activity was increased 1,01 times than crude and with 84.2% of yield. The DPEase had an the maximum temperature is 40°C and pH was 8.5. The presence of Mg2+, Mo2+, Cu2+, Ca2+ and Zn2+ inhibited the activity of the enzyme while of Co2+, Mn2+, Fe2+, Ni2+ enhanced the activity. Estimation of molecular weight through SDS-PAGE revealed that weight of DPEase was 32 kDa. CONCLUSION: Purified DPease enzymes shows clear bands that demonstrate successful purification using affinity chromatography. It is expected that after pure enzymes are obtained the character of the enzymes working will be maximized.