Team:Linkoping Sweden/Project/Culprit

Peanut allergy appears early in life and tends to persist indefinitely compared to other foodallergies. Symptoms ranging from utricaria to severe, systemic anaphylaxis. Different proteins are associated with these clinical reactions. The ara h 1 protein is an important allergen and recognized by 90 % of peanut-sensitive persons. It is 418 aminoacids in length and belongs to the vicilin family of seed storage proteins. The structure consist of two sets of opposing antiparallel β-sheets with terminal regions of α-helical bundles. Ara h 1 is stable to digestion and survives intact in many food processing methods. It contains protease digestion sites which are inaccessible due to the compact tertiary structure.

The body thinks that the protein is a immunological threat and generates IgE, immunoglobin E. IgE binds to ara h 1 protein and activate mastcells to realease histamines, causing an allergic reaction. The mastcell receptors cross-link, inducing a signal transduction that result in degranualtion. Ara h 1 protein consists of 23 IgE-binding epitopes, varying from 6-8 aminoacids in length. There is no common aminoacid sequence between the epitopes. The most critical part of the sequence is the hydrophobic residues. Substituation of a single aminoacid leads to loss of IgE-bindning.