Effect of Cu2+ on Molecular Structure and IgG Binding Capacity of TBt

Abstract

Abstract: Allergenic protein TBt is a major allergen in tartary buckwheat. In order to study the effect of Cu2+ on the structure and allergenicity of TBt, the interaction between Cu2+ and TBt was analyzed using fluorescence method; the structural change was observed by CD and Native-PAGE; the change of allergenicity was identified by indirect ELISA and inhibitory ELISA. The results of fluorescence spectroscopic analysis indicated that Cu2+ could be bound to TBt forming a stable complex at a molar ratio of 1:1; CD analysis showed secondary structure of TBt did not change, but spatial structure of TBt was changed in Native-PAGE. Briefly, the spatial structures of TBt changed into hexamers form under the effect of Cu2+; Inhibitory ELISA and indirect ELISA showed that TBt became hexamer, a part of epitopes were covered and allergenicity was decreased. These investigations provided a theoretical basis for further studies about regulation role of Cu2+ on plant storage proteins in vivo.

Key words: Tartary buckwheat, Allergenic protein, Metallic ions, Hypoallergenic

CLC Number:

Q516
R392

References

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