We constructed enzyme variants of the α-glucosidases from Aspergillus oryzae (AoryAgdS) and Aspergillus sojae (AsojAgdL) by mutating the amino acid residue at position 450. AoryAgdS_H450R acquired the ability to produce considerable amounts of α-1,6-transglucosylation products, whereas AsojAgdL_R450H changed to produce more α-1,3- and α-1,4-transglucosylation products than α-1,6-products. The 450th amino acid residue is critical for the transglucosylation of these α-glucosidases.
Keywords: Aspergillus; site-directed mutagenesis; transglucosylation; α-glucosidase.
© The Author(s) 2021. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.