Molecular cloning and characterization of the α-glucosidase II from Bombyx mori and Spodoptera frugiperda

► We cloned glucosidase II subunit genes from Bombyx mori (BmGlcIIα and BmGlcIIβ) and Spodoptera frugiperda (SfGlcIIα). ► Recombinant glucosidase II subunits (rBmGlcIIα, rBmGlcIIβ, and rSfGlcIIα) were produced by a baculovirus expression system. ► rBmGlcIIα and rSfGlcIIα hydrolyzed p-nitrophenyl α-d-glucopyranoside but not N-glycan. ► The formation of a rBmGlcIIα/rBmGlcIIβ complex was required for N-glycan cleavage. ► rBmGlcIIα was less sensitive than rSfGlcIIα to α-glucosidase inhibitors in mulberry leaves.