Figure 1.

The α- and β-anomers of maltose and the pathway for the enzymatic determination of α- and β-maltose. A, α and β refer to the position of the hydroxide of the hemiacetal at the reducing end of the molecule. In the α-anomer, the OH attached to the anomeric carbon is on the opposite side of the sugar ring from the CH₂OH group. In the β-anomer, the OH is on the same side of the ring as the CH₂OH group. B, Maltose epimerase catalyzes the interconversion of α- and β-maltose. Therefore, it is the strict specificity of maltose phosphorylase for α-maltose and the order in which these enzymes are added to the assay buffer that make the determination of α- and β-maltose possible.