Analysis of the Structural and Immunological Stability of 2S Albumin, Nonspecific Lipid Transfer Protein, and Profilin Allergens from Mustard Seeds.

Departamento de Bioquímica y Biología Molecular, Facultad de Química, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain.
Journal of Agricultural and Food Chemistry (Impact Factor: 3.11). 05/2012; DOI: 10.1021/jf300555h
Source: PubMed

ABSTRACT This work investigates the resistance to proteolysis and heating of the yellow mustard (Sinapis alba L.) allergens Sin a 1 (2S albumin), Sin a 3 (nonspecific lipid transfer protein, LTP), and Sin a 4 (profilin) to explain their potential capability to induce primary sensitization at the gastrointestinal level. Sin a 1 and Sin a 3 resisted gastric digestion showing no reduction of the IgE reactivity. Intestinal digestion of Sin a 1 and Sin a 3 produced a limited proteolysis but retained significant IgE-binding reactivity. Sin a 1 was stable after heating, and although Sin a 3 was modified, most of its structure was recovered after cooling back. These two allergens would be therefore able to sensitize by ingestion. Sin a 4 was completely digested by gastric treatment and its conformational structure markedly modified at 85 °C. Thus, this allergen can be described as a nonsensitizing mustard allergen.

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