The investigation of protein flexibility of various soybean cultivars in relation to physicochemical and conformational properties

The conformation and physicochemical attributes of proteins play important roles in determining their flexibility. This study investigates the structural flexibility of twelve different soybean proteins. Results suggest that amino acids not only affects protein flexibility but its spatial structure as well. In addition, β-conglycinin protein contained more flexible subunits than glycinin. The HN-87, HN-48, HH-44 and HH-53 proteins were more flexible with lower α-helix content. Other key factors that influence higher structural flexibility include higher surface hydrophobicity and fewer disulfide bonds. Furthermore, more flexible proteins ensured the unfolding of the polypeptide chain backbone and endowed them with excellent emulsifying characteristics. In all, flexible proteins showed stronger surface activity than rigid ones. These findings thus provide clear evidence on the structural flexibility-functional properties interactions of different soybean proteins.