Evidence for Interactions among Soybean Protein, Actin and α-Actinin

Abstract

To improve the utilization of soybean proteins in meat products, the interaction of α-actinin and soybean protein with actin was investigated by cosedimentation and viscosity experiments. Analyses of the sedimented proteins clearly demonstrated that soybean proteins can bind to F-actin filaments to some extent under neutral (7.5) or slightly acidic (5.5) pH conditions at 25°C. However, no interaction between α-actinin and soybean proteins was observed. In the presence or absence of soybean protein, no appreciable differences were obsered in the amount of α-actinin that bound to F-actin under neutral pH condition. However, the amount of α-actinin that bound to F-actin in the absence of soybean proteins under acidic pH condition. These results indicated that α-actinin and soybean protein can bind to actin filaments simultaneously. By viscometry it was confirmed that α-actinin and soybean proteins can bind to F-actin.