On the equilibrium between monomeric alpha-lactalbumin and the chaperoningcomplex of alpha-crystallin

In chaperoning dithiothreitol denatured alpha -lactabumin, alpha -crystalli n forms a chaperoning complex. In order to study the kinetics of such chape roning it needs to be established whether the formation of the chaperoning complex is a reversible or irreversible process. The chaperoning reaction w as studied by dynamic light scattering as a function of concentration and w eight ratio of alpha -lactalbumin/alpha -crystallin. HPLC and subsequent SD S-PAGE gel electrophoresis experiments established that the chaperoning com plex formed contains both alpha -crystallin and alpha -lactalbumin. Upon re chromatographing the chaperoning complex, the presence of monomeric alpha - lactalbumin has been demonstrated in addition to the chaperoning complex it self, This and equilibrium dialysis experiments demonstrated conclusively t he existence of an equilibrium between monomeric partially denatured alpha -lactalbumin and the chaperoning complex made of alpha -lactalbumin and alp ha -crystallin. (C) 2001 Academic Press.