Abstract: 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 Z. mobilis to produce levan. The levansucrase is prepared by culturing E. coli 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 E. coli JUD81 (KCTC 0877BP). Also, disclosed are a gene coding for the levan fructotransferase and an expression vector pUDAF81 carrying the gene.

Abstract: Disclosed are Hansenula polymorpha mutants useful as host cells through which various proteins can be produced as being intact at high yield and a process for preparing recombinant proteins using the host cells. Using various vectors, Hansenula polymorpha is made to be a mutant which is deprived of methanol assimilating ability and incapable of utilizing methanol as a carbon source. This Hansenula polymorpha mutant is used as a high yield host to produce recombinant proteins without continuous feeding of methanol, with the aid of an expression cassette carrying a promoter capable of inducing the expression at a low concentration of methanol. Further, the mutant is also lacking in carboxypeptidase Y, protease Y and/or carboxypeptidase a activity, so the recombinant protein of interest is not degraded at its carboxyl terminal when being expressed in the cell. Thus, intact recombinant protein can be obtained.

Abstract: Disclosed are Hansenula polymorpha mutants useful as host cells through which various proteins can be produced as being intact at high yield and a process for preparing recombinant proteins using the host cells. Using various vectors, Hansenula polymorpha is made to be a mutant which is deprived of methanol assimilating ability and incapable of utilizing methanol as a carbon source. This Hansenula polymorpha mutant is used as a high yield host to produce recombinant proteins without continuous feeding of methanol, with the aid of an expression at a cassette carrying a promoter capable of inducing the expression at a low concentration of methanol. Further, the mutant is also lacking in carboxypeptidase Y, protease Y and/or carboxypeptidase &agr; activity, so the recombinant protein of interest is not degraded at its carboxyl terminal when being expressed in the cell. Thus, intact recombinant protein can be obtained.

Abstract: The present invention relates to an animal feed containing the 0.04-2 (w/w) % simple polysaccharide on the basis of solid powder. The animal feed according to this invention is effective in improving the condition of evacuation, preventing the diarrhea and promoting the growth of animals.

Abstract: Disclosed are Hansenula polymorpha mutants useful as host cells through which various proteins can be produced as being intact at high yield and a process for preparing recombinant proteins using the host cells. Using various vectors, Hansenula polymorpha is made to be a mutant which is deprived of methanol assimilating ability and incapable of utilizing methanol as a carbon source. This Hansenula polymorpha mutant is used as a high yield host to produce recombinant proteins without continuous feeding of methanol, with the aid of an expression cassette carrying a promoter capable of inducing the expression at a low concentration of methanol. Further, the mutant is also lacking in carboxypeptidase Y, protease Y and/or carboxypeptidase a activity, so the recombinant protein of interest is not degraded at its carboxyl terminal when being expressed in the cell. Thus, intact recombinant protein can be obtained.