Conclusions:
These results establish vicilin precursors as a family of evolutionarily
distant, yet structurally similar proteins whose allergenic potential
cannot be easily assessed using traditional sequence homology metrics.
The cross-reactive peptides in the LSs are located in the most ordered
region of the structures and are related in their PCPs to immunodominant
epitopes of 2S-albumins. Concurrently, the widespread prevalence of what
we refer to as repeat sequences, in a variety of common food sources,
highlights the need for a combination of structural, bioinformatics and
immunological tools to identify potential cross-reactivity between
taxonomically distant allergen families. This emphasizes that while the
α-hairpin structure is common and is likely to harbor important
conformational epitopes, the location and sequence of the amino acids
within the structure are likely to have a significant impact on the IgE
binding affinity, the digestion sites, and the clinical relevance of IgE
cross-reactivity.