Neopullulanase that cleaves 1,4-alpha-glucosidic linkages in starch to produce disaccharides or trisaccharides in starch degradation. Hydrolysis of pullulan to panose (6-alpha-D-glucosylmaltose). Binds 1 Ca(2+) ion per subunit. Glycan degradation; starch degradation. Reduction by 30% of the rate of growth on starch. Belongs to the glycosyl hydrolase 13 family.