Immunochemical and computational characterization of the major soybean allergen Gly m Bd 30K

CANDREVA ANGELA MARÍA; CURCIARELLO RENATA; GONZÁLEZ, VIRGINIA; PARISI, GUSTAVO; PETRUCCELLI SILVANA; DOCENA, GUILLERMO H.

Viña del Mar, CHILE

Congreso; 9th Latin American Congress of Immunology; 2009

Asociación Latinoamericana de Inmunología, Sociedad Chilena de Inmunología, IUIS

Soy proteins are widely used by food industry. More than 15 allergens have been identified, being Gly m Bd 30K themajor soy allergen. Information regarding the structure and allergenic epitopes may be relevant to understand themolecular basis of the pathology and the previously cross-reactivity with bovine caseins described by our group. Ourobjective was to obtain Gly m Bd 30K as a recombinant protein and to obtain a computational model for epitopemapping.We used a cDNA library of immature soybean, the vectors pENTR SD/TOPO and pDEST-HIS-MBP and several strainsof E.coli BL21 for protein expression. It was obtained as soluble protein and then used in different immunoenzymaticmethods (EAST, ELISA, immunoblotting) with patient sera and cow´s milk-specific polyclonal and monoclonalantibodies. Three peptides containing bioinformatically-proposed IgE epitopes were also cloned and resulted to berecognized by the antibodies. Gly m Bd 30K was modeled and two epitopes were located in the surface.The recombinant Gly m Bd 30K obtained resulted to be immunochemically antigenic and allergenic, two epitopes weremapped and for the first time we built a three dimensional model for this soy allergen. This information may beimportant to reduce its immunoreactivity by genetic engineering.