Structure of the Major Apple Allergen Mal d 1.
More than 70% of birch pollen-allergic patients develop allergic cross-reactions to the major allergen found in apple fruits (Malus domestica), the 17.5 kDa protein Mal d 1. Allergic reactions against this protein result from initial sensitization to the major allergen from birch pollen, Bet v 1. Immunologic cross-reactivity of Bet v 1-specific IgE antibodies with Mal d 1 after apple consumption can subsequently provoke severe oral allergic syndromes. This study presents the three-dimensional NMR solution structure of Mal d 1 (isoform Mal d 1.0101, initially cloned from 'Granny Smith' apples). This protein is composed of a seven-stranded antiparallel β-sheet and three α-helices that form a large internal cavity, similar to Bet v 1 and other cross-reactive food allergens. The Mal d 1 structure provides the basis for elucidating the details of allergic cross-reactivity between birch pollen and apple allergens on a molecular level.
Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck , Innrain 80/82, A-6020 Innsbruck, Austria.
Linda
L
Ahammer
Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck , Innrain 80/82, A-6020 Innsbruck, Austria.
Sarina
S
Grutsch
Institute of General, Inorganic and Theoretical Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck , Innrain 80/82, A-6020 Innsbruck, Austria.
Anna S
AS
Kamenik
Institute of General, Inorganic and Theoretical Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck , Innrain 80/82, A-6020 Innsbruck, Austria.
Klaus R
http://orcid.org/0000-0002-0985-2299
KR
Liedl
Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck , Innrain 80/82, A-6020 Innsbruck, Austria.
Martin
http://orcid.org/0000-0002-2177-983X
M
Tollinger
D052179:Antigens, Plant / Q000737:chemistry* / Q000276:immunology; D027845:Malus / Q000737:chemistry* / Q000276:immunology; D008958:Models, Molecular; D010940:Plant Proteins / Q000737:chemistry* / Q000276:immunology; D000072757:Protein Conformation, beta-Strand
D052179:Antigens, Plant; C095551:MALD1 protein, Malus domestica; D010940:Plant Proteins
Mal d 1; Malus domestica; allergen; structure