New insight into the effects of different glycation treatments on the structure and IgG‐binding capacity of α‐lactalbumin

Abstract

SummaryAlpha‐lactalbumin (α‐LA) is one of the allergens in cow's milk. Glycation modifications can be used to modulate the allergenicity of α‐LA and to clarify the effects of glycation of three reducing sugars (D‐fructose, D‐ribose, and D‐xylose) on the structure and immunoglobulin G (IgG)‐binding capacity of α‐LA. In this study, the colorimetric and spectroscopic methods reflect the degree of glycation. The structural properties of the glycation products were characterised using spectroscopic and chromatographic methods. The IgG‐binding capacity was determined by an indirect competitive enzyme‐linked immunosorbent assay. The results showed a decrease in free amino groups content, an increase in molecular weight. The α‐helix content was reduced, but the β‐sheet and irregular coil content increased, resulting in a more loosened protein structure. All three reducing sugar glycation products had higher IgG‐binding capacity, suggesting that glycation has the potential to enhance α‐LA allergenicity. This study provides different perspectives on the allergenicity of cow's milk allergens modified by different sugar glycations.