Structural Biology

Biography

Biography: Soheila J Maleki

Abstract

Food allergy is on the rise and the prevalence of       peanut allergy       has more than tripled in the U.S. in the last 20 years. Mea nwhile, little is known about why certain proteins in foods are      allergenic      and others are not. Also, it is important to know what happens  to the      allergenicity      of food products after pr ocessing. To assess     processing-induced changes    , the major allergen s were purified from raw (R), and roasted (Ro) peanuts and the structure and     IgE     binding were compared with various    ELISA    and   immunoblots   with  allergic sera ,  circular dic     hroism , mass spectroscopy and e nzymatic digestion. While the structure of the allergens purified following roasting did not show significant changes compared to the raw, the IgE binding and SPT to the roasted samples peanuts were higher. Although allergen structure was found to be more important than linear sequence, it is likely that the roasting-induced chemical modifications are more important for enhanced IgE binding and  immunogenicity  than the structural changes to the major peanut allergens. Mass spectroscopic analysis was utilized to identify specific processing-induced chemical modif ications of the peanut allergens that may contribute to the observed effects. Thermally processed peanut proteins are chemically modified, covalently cross-linked, less soluble, more resistant to digestive enzymes, bind higher levels of IgE, and cause higher skin prick test (SPT) reactivity than raw peanut proteins. This knowledge may be useful in the development of more specific and improved diagnostic, therapeutic and detection tools and potentially lead to development of processes that can result in reduced allergenicity of a food.