Enzymatic production of difructose dianhydride IV from sucrose and relevant enzymes and genes coding for them

Z. mobilis E. coli E. coli Disclosed is the production of difructose dianhydride IV from sugar. A sugar solution is subjected to reaction at room temperature or lower in an acidic buffer of pH 3.0-7.0 in the presence of a levansucrase derived from to produce levan. The levansucrase is prepared by culturing BL21 (DE3)/pEL12 (KCTC 8661), harvesting and homogenizing the cells, and isolating levansucrase from the cell homogenate. Levan is purified from the reaction solution and subjected to reaction at 25-50° C. for 3-10 hours in an acidic buffer of pH 3.0-7.0 in the presence of a levan fructotransferase to produce difructose dianhydride IV. The levan fructotransferase is obtained from JUD81 (KCTC 0877BP). Also, disclosed are a gene coding for the levan fructotransferase and an expression vector pUDAF81 carrying the gene.