Print Email Facebook Twitter Purification and Characterization of Naturally Occurring Post-Translationally Cleaved Ara h 6 an Allergen That Contributes Substantially to the Allergenic Potency of Peanut Title Purification and Characterization of Naturally Occurring Post-Translationally Cleaved Ara h 6 an Allergen That Contributes Substantially to the Allergenic Potency of Peanut Author de Jong, G.A.H. Jayasena, S. Johnson, P. Marsh, J. Apostolovic, D. van Hage, M. Nordlee, J. Baumert, J. Taylor, S.L. Roucairol, C. de Jongh, H. Koppelman, S.J. Publication year 2018 Abstract The 2S albumin Ara h 6 is one of the most important peanut allergens. A post-translationally cleaved Ara h 6 (pAra h 6) was purified from Virginia type peanuts, and the cleavage site was mapped using high-resolution mass spectrometry. Compared to intact Ara h 6, pAra h 6 lacks a 5-amino acid stretch, resembling amino acids 43-47 (UniProt accession number Q647G9) in the nonstructured loop. Consequently, pAra h 6 consists of two chains: an N-terminal chain of approximately 5 kDa and a C-terminal chain of approximately 9 kDa, held together by disulfide bonds. Intermediate post-translationally cleaved products, in which this stretch is cleaved yet still attached to one of the subunits, are also present. The secondary structure and immunoglobulin E (IgE) binding of pAra h 6 resembles that of intact Ara h 6, indicating that the loss of the nonstructured loop is not critical for maintaining the protein structure. Commercially available monoclonal and polyclonal immunoglobulin G (IgG) antibodies directed to Ara h 6 react with both intact Ara h 6 and pAra h 6, suggesting that the involved epitopes are not located in the area that is post-translationally cleaved. No differences between intact Ara h 6 and pAra h 6 in terms of IgE binding were found, suggesting that the area that is post-translationally cleaved is not involved in IgE epitopes either. For all main cultivars Runner, Virginia, Valencia, and Spanish, intact Ara h 6 and pAra h 6 occur in peanut at similar levels, indicating that pAra h 6 is a consistent and important contributor to the allergenic potency of peanut. © Copyright 2018 American Chemical Society. Subject Arachis hypogaeaIgEAllergensAntibodiesChainsCovalent bondsEpitopesMass spectrometryPurificationSulfur compoundsArachis hypogaeaHigh resolution mass spectrometryImmunoglobulin GNaturally occurringpeanutPeanut allergensProtein structuresSecondary structuresOilseeds To reference this document use: http://resolver.tudelft.nl/uuid:d1d726ee-b03e-4021-9f1a-6690c7b31cad DOI https://doi.org/10.1021/acs.jafc.8b03140 TNO identifier 954959 ISSN 0021-8561 Source Journal of Agricultural and Food Chemistry, 66 (66), 10855-10863 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.