Molluscan shellfish, including oysters, often cause allergic reactions in sensitive people throughout the world. It has been demonstrated that arginine kinase (AK) was one of the major allergens of oyster. The present study aimed to evaluate the immunoreactivity and structure of oyster arginine kinase (AK) as affected by heat treatment, pH change, and in vitro digestion. What’s more, the IgE-binding epitopes of this allergen were also predicted and validated.
Thermal and pH assays revealed that AK was unstable at temperature > 40°C or pH ≤5.0 by SDS-PAGE and Circular Dichroism (CD), while the digestibility assays suggested that AK was easier to be digested by pepsin than by trypsin and chymotrypsin. The potential epitopes were predicted through immunoinformatics tools and seven linear epitopes were identified by indirect competition enzyme-linked immunosorbent assay (icELISA) with pooled sera and individual serum from oyster allergic patients. The critical amino acids in each epitope were also confirmed using mutant peptides. These linear epitopes and critical amino acids were apt to distribute on the outer surface of homology-based AK model. Moreover, the three denaturants (SDS, β-Me and urea) can destroy the spatial structure of AK and increase or reduce its allergenicity by denaturation treatments.
Processing conditions lay the foundation for the variation of allergenicity. Seven linear epitopes and the critical amino acids of them were identified by indirect competitive enzyme-linked immunosorbent assay (icELISA). These findings will be helpful in allergy diagnosis and development of hypoallergenic products in the near future. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.