Inhibition of Leucine and Lysine Aminopeptidase by Atopic Allergens

Abstract

MANY atopic allergens—the biologically active substances involved in the syndrome of atopy in man (asthma, hay fever, atopic eczema)—have been shown to incorporate 1-deoxy-2-ketose side chains attached at the sugar carbon C1 to the ε-amino groups of lysine residues in the peptide chain of the protein or glycoprotein carrier molecules^1–3. Recent syntheses have shown that the selective coupling of reducing sugar to the ε-amino functions of lysine side chains in the β-lactoglobulin molecule does in fact increase the specific activity of the protein during skin tests in milk-sensitive individuals⁴. The blockade of a few amine or amide groups by combination with monosaccharides would also provide a plausible explanation for the occurrence of, and for the physicochemical difference between, the “iso-allergens” in extracts of grass pollen⁵.