Alpha-glucosidase with specificity for isomaltose, maltose, and palatinose. Hydrolysis of (1->6)-alpha-D-glucosidic linkages in some oligosaccharides produced from starch and glycogen by alpha-amylase, and in isomaltose. Transcriptionally regulated by PDR8. Expression is increased in response to the addition of maltose, isomaltose, and alpha-methylglucopyranoside. Belongs to the glycosyl hydrolase 13 family.