Cor a 14, the allergenic 2S albumin from hazelnut, is highly thermostable and resistant to gastrointestinal digestion. Issue 10 (6th August 2015)

• Record Type: Journal Article
• Authors: Pfeifer, Sabine; Bublin, Merima; Dubiela, Pawel; Hummel, Karin; Wortmann, Judith; Hofer, Gerhard; Keller, Walter; Radauer, Christian; Hoffmann‐Sommergruber, Karin
• Is Part Of: Molecular nutrition & food research. Volume 59:Issue 10(2015:Oct.)
• Page Start: 2077
• Page End: 2086
• Publication Date: 2015-08-06
• Subjects: Food -- Biotechnology -- Periodicals; Food -- Microbiology -- Periodicals; Nutrition -- Periodicals; Food -- Toxicology -- Periodicals; Nutrition -- Periodicals; Food Microbiology -- Periodicals; Food Technology -- Periodicals; Molecular Biology -- Periodicals; 664.0705
• DOI: 10.1002/mnfr.201500071
• Languages: English
• ISSNs: 1613-4125

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="mnfr2442-sec-0010" sec-type="section"> <title>Scope</title> <p>Allergens from nuts frequently induce severe allergic reactions in sensitive individuals. The aim of this study was to elucidate the physicochemical characteristics of natural Cor a 14, the 2S albumin from hazelnut.</p> </sec> <sec id="mnfr2442-sec-0020" sec-type="section"> <title>Methods and results</title> <p>Cor a 14 was purified from raw hazelnuts using a combination of precipitation and chromatographic techniques. The protein was analyzed using gel electrophoresis, MS, and far‐UV circular dichroism (CD) analyses. The immunoglobulin E (IgE) binding of native, heat‐treated, and in vitro digested Cor a 14 was studied. We identified two different Cor a 14 isoforms and showed microclipping at the C‐terminus. CD spectra at room temperature showed the typical characteristics of 2S albumins, and temperatures of more than 80°C were required to start unfolding of Cor a 14 demonstrating its high stability to heat treatment. In vitro digestion experiments revealed that Cor a 14 is resistant to proteolytic degradation. Native and heat‐treated protein was recognized by sera from hazelnut allergic patients. However, denaturation of the allergen led to significantly reduced IgE binding.</p> </sec> <sec id="mnfr2442-sec-0030" sec-type="section"> <title>Conclusion</title> <p>We identified two different isoforms of Cor a 14 displaying high stability under heating and gastric and duodenal conditions. Data from IgE‐binding experiments revealed the existence of both, linear and conformational epitopes.</p> </sec> </abstract>