A stabilized molten globule protein

A predominant conformational isomer of non-native cl-lactalbumin (alpha -LA) has been purified by thermal denaturation of the native alpha -LA using the technique of disulfide scrambling. This unique isomer retains a substantial content of alpha -helical structure. It is stabilized by two native disulfide bonds within the alpha -helical domain and two scrambled non-native disulfide bonds at the beta -sheet domain. This denatured isomer of alpha -LA exhibits structural characteristics that are consistent with the well-documented molten globule state. The ability to prepare a stabilized and structurally defined molten globule provides a useful model for studying the folding and unfolding pathways of proteins. (C) 2000 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.