Reactivity and Ionization Constants of the Lysine Residues in Apovitellenin I of Emu Egg Yolk Low-density Lipoprotein by Competitive Labelling

Abstract

Competitive labelling with [14C]acetic anhydride over a range of pH values has been used to explore the surface topography of the apovitellenin I moiety in emu egg yolk low-density lipoprotein. The reaction of the lysine e-amino groups with acetic anhydride has been related to pH in a set of titration curves; from these, the reactivities relative to alanine and the ionization constants of all but the amino terminallysines have been determined.