@article {F{\"u}hrer2020.11.27.400978, author = {Sebastian F{\"u}hrer and Anna S. Kamenik and Ricarda Zeindl and Bettina Nothegger and Florian Hofer and Norbert Reider and Klaus R. Liedl and Martin Tollinger}, title = {Structural basis for variable IgE reactivities of Cor a 1 hazelnut allergens}, elocation-id = {2020.11.27.400978}, year = {2020}, doi = {10.1101/2020.11.27.400978}, publisher = {Cold Spring Harbor Laboratory}, 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 correlation between structural flexibility and IgE-binding, 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.Competing Interest StatementThe authors have declared no competing interest.}, URL = {https://www.biorxiv.org/content/early/2020/11/27/2020.11.27.400978}, eprint = {https://www.biorxiv.org/content/early/2020/11/27/2020.11.27.400978.full.pdf}, journal = {bioRxiv} }