Project Number: 6435-43440-020-00
Start Date: Jan 28, 2005
End Date: Nov 30, 2009
Peanuts, tree nuts, and legumes will be subjected to processing, and the allergens will be compared for changes in digestibility and antibody binding (IgE); structural alterations (e.g. changes in secondary structure, cross-linking); solubility and degradation; and functional properties (e.g. oligomerization, enzymatic ability). The prominent allergens from the selected nuts and legumes will be cloned, expressed, and purified and then subjected to specific chemical treatments that mimic reactions that occur during processing. Alterations to structure, function, and allergic properties will be assessed. Amino acid sequences thought to be modified during processing will be altered through specific reactions to confirm modification, and the structural properties will be assessed via circular dichrosim and molecular modeling methods. Protein homology models will be developed for the selected allergens from the different nuts and legumes, and used to determine particular structural or chemical changes empirically determined to alter IgE binding. The structure of small allergens, for which structural information is unavailable for homology modeling, will be subjected to nuclear magnetic resonance (NMR) to resolve their structure. Based on these protein models and empirical data, known functional foods, will be selected and assessed for interfering with antibody recognition of various allergens. Enzyme linked immunosorbent assays will be optimized for recognition of allergens in various food products and processing lines following different processes. To enable regulatory agencies to adopt proper labeling guidelines for manufacturers, threshold dose determination protocols will be developed for processed forms of peanut, tree nut, and soy allergens. Small-scale threshold dose studies will be carried out, and the results will be used to develop computational and statistical models to estimate population thresholds.