Detecting potential IgE-reactive sites on food proteins using a sequence and structure database, SDAP-food.
The high incidence of food allergies, including oral allergy syndrome, represent major considerations when introducing new crops and foods. A new structural database of allergenic proteins, SDAP-Food, http://fermi.utmb.edu/SDAP/, has been developed to aid in predicting the IgE-binding potential of novel food proteins and cross-reactivities among known allergens. The site is designed to facilitate the first steps of a decision tree approach to determine the allergenicity of a given protein, based on the sequence and structural similarity to known allergens and their IgE binding sites. Immunological tests can then be used to confirm the predictions. A hierarchical procedure for identifying potential allergens, using a physical property-based sequence similarity index, has been designed to identify regions that resemble known IgE binding sites. As an example, SDAP tools were used to find food allergen sequences similar to an IgE binding site of the Jun a 3 allergen from mountain cedar pollen. The SDAP sequence similarity search matched the Jun a 3 epitope to regions in several food allergens, including cherry (Pru av 2), apple (Mal d 2) and pepper (Cap a 1), which are, like Jun a 3, members of the plant pathogenesis-related (PR-5) protein family. Homology modeling, using our EXDIS/DIAMOD/FANTOM program suite, indicated a similar surface location and structure for the potential epitope region on all of these allergens. The quantitative approach presented here can be used as part of a screening process for potential allergenicity of recombinant food products.
Ivanciuc
Ovidiu
O
Sealy Center for Structural Biology, Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-1157, USA.
Mathura
Venkatarajan
V
Midoro-Horiuti
Terumi
T
Braun
Werner
W
Goldblum
Randall M
RM
Schein
Catherine H
CH
D000485:Allergens / Q000737:chemistry / Q000276:immunology; D000595:Amino Acid Sequence; D001665:Binding Sites; D030562:Databases, Protein; D005502:Food; D005512:Food Hypersensitivity / Q000276:immunology*; D007073:Immunoglobulin E / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry* / Q000276:immunology*; D011058:Pollen / Q000737:chemistry / Q000276:immunology; D016415:Sequence Alignment
D000485:Allergens; D010940:Plant Proteins; D007073:Immunoglobulin E