Comparison of acid‐induced conformation changes between 7S and 11S globulin in soybean seeds

The acid‐induced conformation changes between 7 and 11 S globulin, the major storage proteins in soybean seeds, were compared by ultraviolet difference spectra, ultracentrifugation and optical rotatory dispersion. Maximum denaturation occurred at approximately pH 2 in both and dissociation of the proteins into subunits and unfolding of the polypeptide chains were observed simultaneously. However, both proteins showed apparent differences in their readiness to undergo acid‐induced denaturation. The differences were particularly remarkable in the presence of 0.1 ionic strength sodium chloride.