Alternaria alternata allergen Alt a 1: A unique β-barrel protein dimer found exclusively in fungi

摘要: Background Alternaria species is one of the most common molds associated with allergic diseases, and 80% species–sensitive patients produce IgE antibodies to a major protein allergen, Alt 1. The structure function 1 unknown. Objective We sought obtain high-resolution using x-ray crystallography investigate structural relationships between other allergens proteins reported in Protein Data Bank. Methods X-ray was used determine by custom-designed set crystallization conditions. An initial model determined application Ta 6 Br 12 2+ cluster single-wavelength anomalous diffraction. Bioinformatic analyses were compare sequence that proteins. Results unique β-barrel comprising 11 β-strands forms "butterfly-like" dimer linked single disulfide bond large (1345 A 2 ) interface. Intramolecular bonds are conserved among homologs. Currently, has no equivalent Bioinformatics suggest found exclusively fungi. Four previously putative IgE-binding peptides have been located on structure. Conclusions unique, dimeric appears define new family unknown location antibody–binding epitopes agreement analysis will allow mechanistic structure/function studies immunologic directed toward immunotherapy for patients.