| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new amylase for baking, containing a specific amino acid sequence, having α-amylase activity, and a specific thermostability suitable for baking, providing a bread having an increased volume and improved softness, effective for preventing bread aging. SOLUTION: This variant α-amylase contains an amino acid sequence in which one or plural amino acids are deleted from, inserted into or substituted for those of an amino acid sequence of the formula, has α-amylase activity, remaining α-amylase activity after treatment at 65 deg.C for 30 minutes lower than 80% before the treatment and thermostability suitable for use in baking, is effective for increasing bread volume, improving softness are preventing aging and is useful for baking. The enzyme is obtained by treating a DNA encoding the enzyme or a cell containing the DNA with a mutagenic substance, transducing the obtained variant DNA into a host cell, screening and selecting an α-amylase having a desirable thermostability. |
