Sequence Analysis and Biochemical Characterization of Two Non-specific Lipid Transfer Proteins from Tartary Buckwheat Seeds

Abstract Plant non-specific lipid transfer proteins (nsLTPs) exert various biological activities that are valuable for agronomy, industrial manufacturing, and medicine. In this study, two nsLTPs derived from Tartary buckwheat, namely FtLTP1a and FtLTP1b, were produced by gene cloning, expression and purification. Sequence analysis and biochemical characteristics of the proteins, including lipid binding ability, α-amylase inhibition activity, antifungal activity, and allergenic activity, were investigated. Both FtLTP1a and FtLTP1b exhibited similar lipid binding and antifungal properties, but only FtLTP1b showed weak inhibitory activity against α-amylase from the porcine pancreas. Finally, the binding ability of the two protein to IgE antibodies in serum samples from nine patients allergic to buckwheat was assayed using ELISA to investigate their allergenic activity. The data suggested that FtLTP1b not only specifically bound to IgE in serum but also cross-reacted with artemisia pollen allergen (W6). These findings can give constructive suggestions for understanding of cross-reactivity and specificity of nsLTPs.