On the Reactivity of Disulfide Groups of Gliadin and Glutenin

Gliadin and glutenin were treated with various concentrations of 2-mercaptoethanol (ME) at pH 6.0 and their effects on protein disulfides were investigated. The treatment caused polymerization of gliadin, demonstrating the involvement of its disulfides in SH-SS exchange reaction. A plot of SH liberation of protein against ME concentration revealed the existence of a group of glutenin disulfides which reacted rapidly and quantitatively even in the low concentrations of ME, where reaction of the other disulfides was very slow. Most of gliadin disulfides were slowly reacting disulfides.