Related Experiment Video
Updated: Jul 1, 2025
08:58
Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques
Published on: July 5, 2018
12.7K
Novel post-translationally cleaved Ara h 2 proteoforms: Purification, characterization and IgE-binding properties
Stef J Koppelman1, Govardus A H de Jong2, Justin Marsh1
1Food Allergy Research and Resource Program, Department of Food Science & Technology, University of Nebraska, 279 Food Innovation Center, Lincoln, NE 68588-6207, USA.
International Journal of Biological Macromolecules
|March 6, 2024
Summary
Newly discovered peanut allergen Ara h 2 proteoforms, resulting from post-translational cleavage, exhibit similar IgE-binding and allergenicity to intact Ara h 2. These findings are crucial for understanding peanut allergy triggers.
Area of Science:
- Food allergy research
- Protein biochemistry
- Immunology
Background:
- Peanut allergy is a significant health concern, with 2S albumins Ara h 2 and Ara h 6 being major allergens.
- Existing knowledge describes several isoforms of these peanut allergens.
Purpose of the Study:
- To identify and characterize novel proteoforms of the peanut allergen Ara h 2.
- To investigate the structural and allergenic properties of these newly identified Ara h 2 proteoforms.
Main Methods:
- Protein extraction and liquid chromatography were employed to isolate Ara h 2-homologous proteins.
- High-resolution mass spectrometry was used to pinpoint cleavage sites.
- Far-UV circular dichroism (CD) spectroscopy assessed protein structure.
- IgE-binding assays were performed using sera from peanut-sensitized individuals.
Main Results:
- Hitherto unknown Ara h 2 proteoforms with additional post-translational cleavage were identified.
- The cleavage site was located on a non-structured loop, with cleaved forms found in common peanut genotypes.
- These cleaved Ara h 2 proteoforms demonstrated comparable IgE-binding potency and structural similarity to intact Ara h 2.
Conclusions:
- Newly identified cleaved proteoforms of Ara h 2 are structurally similar to the intact allergen.
- These novel proteoforms exhibit comparable IgE-binding capacity, suggesting similar allergenic potential.
- The identified Ara h 2 proteoforms represent relevant contributors to peanut allergenicity.
