PARTIALLY FOLDED STRUCTURE OF MONOMERIC BOVINE BETA-LACTOGLOBULIN

Bovine beta-LG (beta-lactoglobulin) has been studied under a variety o f solution conditions by one- and two-dimensional NMR spectroscopy. At highly acidic pH (pH = 2) and low ionic strength the protein is prese nt in a monomeric form, exhibiting a highly structured beta-sheet core and less ordered regions as evidenced by both CD data and the NOESY s pectra. Marginal protection was observed for most of the amide protons as a result of high conformational mobility. This structural state of beta-LG may be considered as an attractive model for a partially fold ed structure occurring late in the folding process of the protein.