However, other reducing
agents such as ascorbate may also participate in this
reduction (Zhang et al. 1992). Lenzen et al. (1987)
proposed that one of the SH-containing compounds
essential for proper glucose-induced insulin secretion is
glucokinase (EC 2.7.1.2), being very vulnerable to
alloxan. Alloxan reacts with two -SH groups in the sugarbinding
side of glucokinase resulting in the formation of
the disulfide bond and inactivation of the enzyme.
Glucose can protect glucokinase against the inactivation
hindering the access of alloxan to the -SH groups of the
enzyme