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Effect of heat treatment on the conformational stability of intact and cleaved forms of the peanut allergen Ara h 6 in relation to its IgE-binding potency

de Jongh, H.H.J. (author), de Jong, G.A.H. (author), Apostolovic, D. (author), Taylor, S.L. (author), Baumert, J.L. (author), Koppelman, S.J. (author)

This work reports on the effect of heat treatment on the protein conformational stability of intact and post-translationally cleaved peanut allergen Ara h 6 in relation to IgE-binding. Intact and post-translationally cleaved Ara h 6 are structurally similar and their strong resistance to denaturant-induced unfolding is comparable. Only upon...

article 2020

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Purification and Characterization of Naturally Occurring Post-Translationally Cleaved Ara h 6 an Allergen That Contributes Substantially to the Allergenic Potency of Peanut

de Jong, G.A.H. (author), Jayasena, S. (author), Johnson, P. (author), Marsh, J. (author), Apostolovic, D. (author), van Hage, M. (author), Nordlee, J. (author), Baumert, J. (author), Taylor, S.L. (author), Roucairol, C. (author), de Jongh, H. (author), Koppelman, S.J. (author)

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...

article 2018

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Release of major peanut allergens from their matrix under various pH and simulated saliva conditions—Ara h2 and ara h6 are readily bio-accessible

Koppelman, S.J. (author), Smits, M. (author), Tomassen, M. (author), de Jong, G.A.H. (author), Baumert, J. (author), Taylor, S.L. (author), Witkamp, R. (author), Veldman, R.J. (author), Pieters, R. (author), Wichers, H. (author)

The oral mucosa is the first immune tissue that encounters allergens upon ingestion of food. We hypothesized that the bio-accessibility of allergens at this stage may be a key determinant for sensitization. Light roasted peanut flour was suspended at various pH in buffers mimicking saliva. Protein concentrations and allergens profiles were...

article 2018

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A subset of walnut allergic adults is sensitized to walnut 11S globulin Jug r 4

Blankestijn, M.A. (author), den Hartog Jager, C.F. (author), Blom, W.M. (author), Otten, H.G. (author), de Jong, G.A.H. (author), Gaspari, M. (author), Houben, G.F. (author), Knulst, A.C. (author), Verhoeckx, K.C.M. (author)

Background: The role of sensitization to commercially available allergens of English walnut (Juglans regia) Jug r 1, 2 and 3 in walnut allergy has been previously investigated in walnut allergic adults and was unable to explain all cases of walnut allergy. Objectives: Identify recognized walnut allergens, other than the ones previously...

article 2018

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Detection of peanut allergen in human blood after consumption of peanuts is skewed by endogenous immunoglobulins

Janssen-Duijghuijsen, L.M. (author), Wichers, H.J. (author), van Norren, K. (author), Keijer, J. (author), Baumert, J.L. (author), de Jong, G.A.H. (author), Witkamp, R.F. (author), Koppelman, S.J. (author)

Some studies have suggested that allergens may appear in the circulation after ingestion of allergenic food sources. The reported levels of allergen in serum, however, are low, and conclusions between studies differ. Here, we investigated factors that determine the detection of allergens in serum after consumption of peanuts. Ten healthy...

article 2017

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Conformational stability of digestion-resistant peptides of peanut conglutins reveals the molecular basis of their allergenicity

Danijela Apostolovic, D. (author), Dragana Stanic-Vucinic, D. (author), de Jongh, H.H.J. (author), de Jong, G.A.H. (author), Mihailovic, J. (author), Radosavljevic, J. (author), Radibratovic, M. (author), Nordlee, J.A. (author), Baumert, J.L. (author), Milcic, M. (author), Taylor, S.L. (author), Garrido Clua, N. (author), Cirkovic Velickovic, T. (author), Koppelman, S.J. (author)

Conglutins represent the major peanut allergens and are renowned for their resistance to gastro-intestinal digestion. Our aim was to characterize the digestion-resistant peptides (DRPs) of conglutins by biochemical and biophysical methods followed by a molecular dynamics simulation in order to better understand the molecular basis of food...

article 2016

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Allergenicity attributes of different peanut market types

Koppelman, S.J. (author), Jayasena, S. (author), Luykx, D. (author), Schepens, E. (author), Apostolovic, D. (author), de Jong, G.A.H. (author), Isleib, T.G. (author), Nordlee, J. (author), Baumert, J. (author), Taylor, S.L. (author), Cheng, H. (author), Maleki, S. (author)

Four different market classes of peanut (Runner, Virginia Spanish, and Valencia) are commonly consumed in Western countries, but for some consumers peanuts are a main cause of food-induced anaphylaxis. Limited information is available on the comparative allergenicity of these distinct market classes. The aim of this study was to compare...

article 2016

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Recovery of protein from green leaves: verview of crucial steps for utilisation

Tamayo Tenorio, A. (author), Gieteling, J. (author), de Jong, G.A.H. (author), Boom, R.M. (author), van der Goot, A.J. (author)

Plant leaves are a major potential source of novel food proteins. Till now, leaf protein extraction methods mainly focus on the extraction of soluble proteins, like rubisco protein, leaving more than half of all protein unextracted. Here, we report on the total protein extraction from sugar beet leaves (Beta vulgaris L.) by a traditional thermal...

article 2016

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Characterization of Heat-Set Gels from RuBisCO in Comparison to Those from Other Proteins

Martin, A.H. (author), Nieuwland, M. (author), de Jong, G.A.H. (author)

To anticipate a future shortage in functional proteins, it is important to study the functionality of new alternative protein sources. Native RuBisCO was extracted from spinach, and its gelation behavior was compared to other native proteins from animal and plant origins. Protein gels were analyzed for their mechanical gel properties during...

article 2014

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House dust mite (Der p 10) and crustacean allergic patients may react to food containing Yellow mealworm proteins

Verhoeckx, K.C.M. (author), van Broekhoven, S. (author), den Hartog-Jager, C.F. (author), Gaspari, M. (author), de Jong, G.A.H. (author), Wichers, H.J. (author), van Hoffen, E. (author), Houben, G.F. (author), Knulst, A.C. (author)

Scope: Due to the imminent growth of the world population, shortage of protein sources for human consumption will arise in the near future. Alternative and sustainable protein sources (e.g. insects) are being explored for the production of food and feed. In this project, the safety of Yellow mealworms (Tenebrio molitor L.) for human consumption...

article 2014

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Reduction and alkylation of peanut allergen isoforms Ara h 2 and Ara h 6; Characterization of intermediate- and end products

Apostolovic, D. (author), Luykx, D. (author), Warmenhoven, H. (author), Verbart, D. (author), Stanic-Vucinic, D. (author), de Jong, G.A.H. (author), Velickovic, T.C. (author), Koppelman, S.J. (author)

Conglutins, the major peanut allergens, Ara h 2 and Ara h 6, are highly structured proteins stabilized by multiple disulfide bridges and are stable towards heat-denaturation and digestion. We sought a way to reduce their potent allergenicity in view of the development of immunotherapy for peanut allergy. Isoforms of conglutin were purified,...

article 2013

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Natural Ingredients and Foods: A Practical Approach for Qualification

Heeres, H.L. (author), de Jong, G.A.H. (author), Hübner, F. (author), Wassink, G. (author)

The term “natural” in food labelling is increasingly used by producers to indicate that their products are “natural”. The use of this term is not well regulated in many countries, leading to confusion among consumers as well as food producers and legislators and to a lack of guidance for food producers. The authors prepared a pragmatic method...

article 2013

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Parvalbumin in fish skin-derived gelatin: Is there a risk for fish allergic consumers?

Koppelman, S.J. (author), Nordlee, J.A. (author), Lee, P.W. (author), Happe, R.P. (author), Hessing, M. (author), Norland, R. (author), Manning, T. (author), Deschene, R. (author), de Jong, G.A.H. (author), Taylor, S.L. (author)

The major allergen parvalbumin was purified from cod muscle tissues, and polyclonal antibodies were raised towards it. The antibodies were tested for specificity and an enzyme-linked immunosorbent assay (ELISA) was developed using these antibodies. The ELISA was applied to measure parvalbumin in cod skin, the starting material for fish gelatin...

article 2012

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Impact of protein pre-treatment conditions on the iron encapsulation efficiency of whey protein cold-set gel particles

Martin, A.H. (author), de Jong, G.A.H. (author)

This paper investigates the possibility for iron fortification of food using protein gel particles in which iron is entrapped using cold-set gelation. The aim is to optimize the iron encapsulation efficiency of whey protein by giving the whey protein different heat treatment prior to gelation with iron. The effect of the heat treatment...

article 2012

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Enhancing the in vitro Fe2+ bio-accessibility using ascorbate and cold-set whey protein gel particles

Martin, A.H. (author), de Jong, G.A.H. (author)

article 2012

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Reducing the sodium content of meat products

de Jong, G.A.H. (author), Verkleij, T.J. (author)

conference paper 2011

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Digestion of peanut allergens Ara h 1, Ara h 2, Ara h 3, and Ara h 6: A comparative in vitro study and partial characterization of digestion-resistant peptides

TNO Kwaliteit van Leven (author), Koppelman, S.J. (author), Hefle, S.L. (author), Taylor, S.L. (author), de Jong, G.A.H. (author)

Scope: There are differences in stability to pepsin between the major allergens in peanut; however, data are from different reports using different digestion models. This study provides a comprehensive comparison of the digestibility of the major peanut allergens.Methods and results: Peanut allergens Ara h 1, Ara h 2, Ara h 3 and Ara h 6 were...

article 2010

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Purification and immunoglobulin E-binding properties of peanut allergen Ara h 6: Evidence for cross-reactivity with Ara h 2

Koppelman, S.J. (author), de Jong, G.A.H. (author), de Laaper-Ertmann, M. (author), Peeters, K.A.B.M. (author), Knulst, A.C. (author), Hefle, S.L. (author), Knol, E.F. (author), TNO Kwaliteit van Leven (author)

Background: IgE-binding peanut proteins smaller than 15 kDa were previously identified as potential allergens in the majority of our peanut allergic population. Objective: To characterize the novel allergen in order to determine whether it was similar to one of the thus far identified recombinant peanut allergens (Ara h 1-7). Methods: An IgE...

article 2005

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The effect of the food matrix on In Vivo immune responses to purified peanut allergens

van Wijk, F. (author), Nierkens, S. (author), Hassing, I. (author), Feijen, M. (author), Koppelman, S.J. (author), de Jong, G.A.H. (author), Pieters, R. (author), Knippels, L.M.J. (author), TNO Kwaliteit van Leven (author)

There is little knowledge about the factors that determine the allergenicity of food proteins. One aspect that remains to be elucidated is the effect of the food matrix on immune responses to food proteins. To study the intrinsic immunogenicity of allergens and the influence of the food matrix, purified peanut allergens (Ara h 1, Ara h 2, Ara h...

article 2005

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Transglutaminase-Mediated Modification of Glutamine and Lysine Residues in Native Bovine β-Lactoglobulin

Nieuwenhuizen, W.F. (author), Dekker, H.L. (author), Gröneveld, T. (author), de Koster, C.G. (author), de Jong, G.A.H. (author), TNO Voeding (author)

Bovine β-lactoglobulin (BLG) is a major component in whey and its physical properties are important for the texture of many dairy-based foods. Modification of proteins with transglutaminase from Streptoverticillium mobaraense (MTGase) can be used to alter their physical properties. MTGase-mediated modification of native BLG was until now,...

article 2004