Development of an inexpensive, simple purification method for ω-5 gliadin from wheat flour

ω-5 gliadin is a major causative allergen associated with various types of wheat allergy, including wheat-dependent exercise-induced anaphylaxis. Recently, ω-5 gliadin-deficient wheat has been developed. However, several wheat protein studies do not use standard ω-5 gliadin because its naturally derived form is expensive, and purifying it in-house is time-consuming. Therefore, we sought to develop an inexpensive, simple method for purifying ω-5 gliadin on a small scale.▪We compared ω-5 gliadin-deficient wheat with normal wheat and screened for ω-5 gliadin bands using acid-polyacrylamide gel electrophoresis (A-PAGE) on a mini-slab electrophoresis apparatus.▪The ω-5 gliadin band was excised and sealed in dialysis tubing, and the protein was electroeluted using agarose gel electrophoresis. After electroelution, the eluted solution was filtered, dialyzed, and then freeze-dried.▪The main band of collected proteins migrated at approximately 55 kDa in SDS-PAGE, and the most intense band was identified as ω-5 gliadin using nano-LC-MS/MS.