The reaction between proteins and reducing sugars in the ‘dry’ state. Relative reactivity of the α- and ∈-amino groups of insulin

In a study ofthe reaction between casein and glucose in freeze-dried systems Lea & Hannan (1950) obtained an indication that the few terminal a-amino groups present in casein possess a reactivity towards glucose of the same order as that of the 6-amino groups of the lysine residues. Gottschalk & Partridge (1950), on the other hand, found that in the reaction between amino-acids and reducing sugars the reactivity of the amino group increases as