Hydrolysis of raw rice starch by a chimeric α-amylase engineered with α-amylase from Clostridium butyricum T-7

Abstract:

[Objective] To obtain efficient raw rice starch-digesting enzymes. [Methods] α-Amylase AmyP can hydrolyze raw rice starch efficiently. We constructed a chimeric α-amylase (AmyP-Clo) by fusion of the catalytic domain of AmyP and a starch binding domain of α-amylase from Clostridium butyricum T-7. [Results] AmyP-Clo retained the advantages of AmyP, and increased catalytic efficiency towards raw rice starch. The specific activity was (373.9±8.4) U/mg. The final hydrolysis degree was (42.7±1.1)% for the hydrolysis of 5% raw rice starch suspension after 4 h. The maximal fraction of bound protein was (71.1±1.6)%. [Conclusion] AmyP-Clo could efficiently hydrolyze raw rice starch.