CHARACTERIZATION OF MONOCLONAL-ANTIBODIES AGAINST BETA-CONGLYCININ FROM SOYA BEAN (GLYCINE-MAX) AND THEIR USE AS PROBES FOR THERMAL-DENATURATION

A panel of four monoclonal antibodies (Mabs) was raised against beta-conglycinin, the 7S globulin from soya bean. The antibodies were characterised by using direct and competitive enzyme-linked immunosorbent assays (ELISAs), immunoblotting procedures and by analysis of subunit fractions obtained after anion exchange chromatography. All the Mabs were specific for beta-conglycinin, recognising the acidic alpha- and alpha'-subunits. One of the Mabs (IRFN 0089) was used to probe the structural changes that take place during thermal denaturation of beta-conglycinin. A two-site ELISA was developed to observe structural changes in beta-conglycinin with heating. Antibody recognition of heated conglycinin increased with temperature reaching a maximum at 65 degrees C; beta-conglycinin heated to this temperature was recognised three-fold better than unheated beta-conglycinin. At a higher temperature (65-95 degrees C) beta-conglycinin immunoreactivity remained at least two-fold higher than that of the unheated protein. Differential scanning calorimetry data showed the maximum binding of Mab 0089 to correspond with the thermal transition of the beta-conglycinin molecule. The use of the panel of antibodies as structural probes is discussed together with further possible applications of this technology in food chemistry.