Allergic cross-reactivity made visible: solution structure of the major cherry allergen Pru av 1.
Birch pollinosis is often accompanied by hypersensitivity to fruit as a consequence of the cross-reaction of pollen allergen-specific IgE antibodies with homologous food proteins. To provide a basis for examining the cross-reactivity on a structural level, we used heteronuclear multidimensional NMR spectroscopy to determine the high-resolution three-dimensional structure of the major cherry allergen, Pru av 1, in solution. Based on a detailed comparison of the virtually identical structures of Pru av 1 and Bet v 1, the major birch pollen allergen, we propose an explanation for a significant aspect of the observed cross-reactivity pattern among the family of allergens under consideration. The large hydrophobic cavity expected to be important for the still unknown physiological function of Bet v 1 is conserved in Pru av 1. Structural homology to a domain of human MLN64 associated with cholesterol transport suggests phytosteroids as putative ligands for Pru av 1. NMR spectroscopy provides experimental evidence that Pru av 1 interacts with phytosteroids, and molecular modeling shows that the hydrophobic cavity is large enough to accommodate two such molecules.
Neudecker
P
P
Lehrstuhl für Biopolymere, Universität Bayreuth, D-95440 Bayreuth, Germany.
Schweimer
K
K
Nerkamp
J
J
Scheurer
S
S
Vieths
S
S
Sticht
H
H
Rösch
P
P
D000485:Allergens; D000595:Amino Acid Sequence; D052179:Antigens, Plant; D003429:Cross Reactions; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology* / Q000628:therapy; D007167:Immunotherapy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D010940:Plant Proteins / Q000737:chemistry* / Q000276:immunology; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000276:immunology; D017386:Sequence Homology, Amino Acid
D000485:Allergens; D052179:Antigens, Plant; C109472:PRUA1 protein, Prunus avium; D010940:Plant Proteins; D011994:Recombinant Proteins