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Inverse relation between structural flexibility and IgE reactivity of Cor a 1 hazelnut allergens.

ABSTRACT: A major proportion of allergic reactions to hazelnuts (Corylus avellana) are caused by immunologic cross-reactivity of IgE antibodies to pathogenesis-related class 10 (PR-10) proteins. Intriguingly, the four known isoforms of the hazelnut PR-10 allergen Cor a 1, denoted as Cor a 1.0401-Cor a 1.0404, share sequence identities exceeding 97% but possess different immunologic properties. In this work we describe the NMR solution structures of these proteins and provide an in-depth study of their biophysical properties. Despite sharing highly similar three-dimensional structures, the four isoforms exhibit remarkable differences regarding structural flexibility, hydrogen bonding and thermal stability. Our experimental data reveal an inverse relation between structural flexibility and IgE-binding in ELISA experiments, with the most flexible isoform having the lowest IgE-binding potential, while the isoform with the most rigid backbone scaffold displays the highest immunologic reactivity. These results point towards a significant entropic contribution to the process of antibody binding.

SUBMITTER: Fuhrer S

PROVIDER: S-EPMC7892832 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Inverse relation between structural flexibility and IgE reactivity of Cor a 1 hazelnut allergens.

Führer Sebastian S Kamenik Anna S AS Zeindl Ricarda R Nothegger Bettina B Hofer Florian F Reider Norbert N Liedl Klaus R KR Tollinger Martin M

Scientific reports 20210218 1

A major proportion of allergic reactions to hazelnuts (Corylus avellana) are caused by immunologic cross-reactivity of IgE antibodies to pathogenesis-related class 10 (PR-10) proteins. Intriguingly, the four known isoforms of the hazelnut PR-10 allergen Cor a 1, denoted as Cor a 1.0401-Cor a 1.0404, share sequence identities exceeding 97% but possess different immunologic properties. In this work we describe the NMR solution structures of these proteins and provide an in-depth study of their bio ...[more]

PMID: 33603065

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Inverse relation between structural flexibility and IgE reactivity of Cor a 1 hazelnut allergens.

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Inverse relation between structural flexibility and IgE reactivity of Cor a 1 hazelnut allergens.

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