| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject new enzyme, comprising a super thermostable 4-α-glucanotransferase having the optimal temperature close to the boiling point of water, having excellent saccharide transfer actions under high- temperature conditions and useful for industrial production, etc., of high-purity maltooligosaccharides, etc. SOLUTION: This new super thermostable 4-α-glucanotransferase has the optimal pH about 6.0-8.0, the optimal temperature of about 100 deg.C at pH7.5, remains at least >=90% activities after heat treatment at pH7.5 and 100 deg.C for 30min, further actions on transfer of one or several glucose units in α-1,4-glucan to the α-1,4-glucan through 1,4-glucoside bonds and excellent saccharide transfer actions under high-temperature conditions and is useful for industrial preparation of high-purity maltooligosaccharide and synthesis, etc., of various heterooligosaccharides. The enzyme is obtained by providing a DNA fragment containing a gene capable of producing the 4-α-glucanotransferase from a KOD-1 strain (FERM P-15007) and then using a gene recombination technique. |
