Protein engineering of glucoamylase to increase ph optimum, substrate specificity and thermostability

Abstract From the Canadian patent

A fungal glucoamylase including a mutation pair Asn20Cys coupled with Ala27Cys forming a disulfide bond between the two members of the pair. The mutation provides increased thermal stability and reduced isomaltose formation to the enzyme. A fungal glucoamylase including a 311-314Loop mutation wherein , reduced isomaltose formation is provided by the mutation is also provided. A , fungal glucoamylase including a mutation Ser411Ala wherein increased pH optimum and reduced isomaltose formation is provided by the mutation is also , provided. Combinations of the mutations in engineered glucoamylases are also provided as are combinations with other glucoamylase mutations that provide …