Skip to Main content Skip to Navigation
Journal articles

Critical structural elements for the antigenicity of wheat allergen LTP1 (Tri a 14) revealed by site-directed mutagenesis

Abstract : Lipid transfer proteins (LTPs) were identified as allergens in a large variety of pollens and foods, including cereals. LTPs belong to the prolamin superfamily and display an α-helical fold, with a bundle of four α-helices held together by four disulfide bonds. Wheat LTP1 is involved in allergic reactions to food. To identify critical structural elements of antibody binding to wheat LTP1, we used site-directed mutagenesis on wheat recombinant LTP1 to target: (i) sequence conservation and/or structure flexibility or (ii) each disulfide bond. We evaluated the modifications induced by these mutations on LTP1 secondary structure by synchrotron radiation circular dichroism and on its antigenicity with patient’s sera and with mouse monoclonal antibodies. Disruption of the C28–C73 disulfide bond significantly affected IgE-binding and caused protein denaturation, while removing C13–C27 bond decreased LTP1 antigenicity and slightly modified LTP1 overall folding. In addition, we showed Lys72 to be a key residue; the K72A mutation did not affect global folding but modified the local 3D structure of LTP1 and strongly reduced IgE-binding. This work revealed a cluster of residues (C13, C27, C28, C73 and K72), four of which embedded in disulfide bonds, which play a critical role in LTP1 antigenicity.
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-03736832
Contributor : Hamza Mameri Connect in order to contact the contributor
Submitted on : Thursday, August 4, 2022 - 4:06:16 PM
Last modification on : Monday, August 29, 2022 - 2:41:34 PM

File

Mameri-SR-2022-CC-BY.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Hamza Mameri, Jean-Charles Gaudin, Virginie Lollier, Olivier Tranquet, Chantal Brossard, et al.. Critical structural elements for the antigenicity of wheat allergen LTP1 (Tri a 14) revealed by site-directed mutagenesis. Scientific Reports, Nature Publishing Group, 2022, 12 (1), pp.12253. ⟨10.1038/s41598-022-15811-5⟩. ⟨hal-03736832⟩

Share

Metrics

Record views

41

Files downloads

0