Association-dissociation of glycinin in urea, guanidine hydrochloride and sodium dodecyl sulphate solutions.

The effect of urea, guanidine hydrochloride and sodium dodecyl sulphate on glycinin, the high molecular weight protein fraction from soybean has been investigated by analytical ultracentrifugation. Urea and guanidine hydrochloride dissociate the protein to a '2S' protein through the intermediary 7S and 4S proteins. However, in sodium dodecyl sulphate the protein directly dissociates to a 2S protein. Analysis of the data by calculation of per cent fraction and S20,w value indicates that dissociation and denaturation of glycinin occur simultaneously in the presence of the above reagents but to different extents.