FIGURE 4.

Identification of maltohexaose produced using maltotetraose as the acceptor. A large scale incubation was prepared with maltotetraose (2 mg), 50 nmol of [¹⁴C]-maltose-1-P (150,000 cpm), 25 mm Tris buffer, and enzyme (50 μg) in a final volume of 0.5 ml. After an incubation of 60 min, reactions were stopped by heating, and the methanol supernatant liquid was taken to dryness. The residue was dissolved in 2 ml of water and treated with mixed-bed ion-exchange resin to remove salt and other charged molecules. The neutral fraction was subjected to paper chromatography on Whatman 3MM paper in solvent A. Standards of various maltooligosaccharides were run on the same papers to determine the size of any newly formed malto-oligosaccharides. The radioactive band was cut into 1-cm strips and subjected to scintillation counting. Standard sugars were as follows: maltohexose (HEX), maltopentose (PEN), maltotetraose (TET), and maltotriose (TRI).