Covalent polyphenol modification of a reactive cysteine in the major apple allergen Mal d 1.
Food Chem
; 410: 135374, 2023 Jun 01.
Article
em En
| MEDLINE
| ID: mdl-36608553
ABSTRACT
Naturally occurring polyphenols can modify the molecular properties of food allergens. For the major apple allergen Mal d 1 it has been postulated that chemical reactions with polyphenols cause permanent changes in the tertiary structure, causing a loss of conformational IgE epitopes and reducing allergenicity. In our study, we investigated the effect that reactions with oxidized polyphenols have on the structure of Mal d 1 by mass spectrometry and NMR spectroscopy. We showed that a surface-exposed cysteine residue in this allergen spontaneously reacts with oxidized polyphenols under formation of a defined covalent adduct. Chemical modification of Mal d 1 did not destabilize or perturb the three-dimensional fold, nor did it interfere with ligand binding to its internal pocket. A structural model of the chemically modified apple allergen is presented, which reveals that the bound polyphenol partially covers a conformational IgE epitope on the protein surface.
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Base de dados:
MEDLINE
Assunto principal:
Malus
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article