SDAP is a Web server that integrates a database of allergenic proteins with various computational tools that can assist structural biology studies related to allergens. SDAP is an important tool in the investigation of the cross-reactivity between known allergens, in testing the FAO/WHO allergenicity rules for new proteins, and in predicting the IgE-binding potential of genetically modified food proteins.
Read an SDAP Overview or select a SDAP function from the left column.
AllergenAI New!
AI-powered allergenicity prediction from protein sequence using deep learning.
Launch AllergenAI →FAO/WHO Allergenicity Test
Evaluate potential allergenicity using the FAO/WHO decision tree (2001).
Run Test →Peptide Match
Find exact peptide sequence matches across all SDAP allergen sequences.
Peptide Match →Peptide Similarity
PD physico-chemical descriptor similarity search against all allergens.
Peptide Similarity →Peptide–Protein PD Index
Compare two protein or peptide sequences using the PD index method.
PD Index →- Liu J, Negi SS, Yang C, Zhou X, Schein CH, Braun W, Kim P. AllergenAI: a deep learning model predicting allergenicity based on protein sequence. BMC Bioinformatics. 2025;26(1):279. [Abstract] [Full Paper]
- Negi SS, Schein CH, Braun W. The updated Structural Database of Allergenic Proteins (SDAP 2.0) provides 3D models for allergens and incorporated Bioinformatics Tools. J Allergy Clin Immunol Glob. 2023;2(4):100162. [Abstract] [Full Paper]
- Schein CH, Negi SS, Braun W. Still SDAPing Along: 20 Years of the Structural Database of Allergenic Proteins. Front. Allergy 3:863172. [Full Paper]
- Ivanciuc O, Schein CH, Braun W. SDAP: Database and Computational Tools for Allergenic Proteins. Nucleic Acids Res. 2003;31(1):359–362. [PubMed]
- Ivanciuc O, Schein CH, Braun W. Data Mining of Sequences and 3D Structures of Allergenic Proteins. Bioinformatics 2002;18(10):1358–1364. [PubMed]
- Negi SS, Goldblum R, Braun W, Horiuti TM. Design of peptides with high affinity binding to a monoclonal antibody. Peptides. 145:170628, 2021. [PubMed]
- Dreskin SC, Koppelman SJ et al. The importance of the 2S albumins for allergenicity and cross-reactivity. J Allergy Clin Immunol 147(4):1154–1163, 2021. [PubMed]
- Lu W, Negi SS, Schein CH et al. Distinguishing allergens from non-allergenic homologues using PCP motifs. Mol Immunol, 9:1–8, 2018. [PubMed]
- Negi SS, Braun W. Cross-React: a new structural bioinformatics method for predicting allergen cross-reactivity. Bioinformatics, 33(7):1014–1020, 2017. [PubMed]
- Ivanciuc O et al. AllerML: Markup language for allergens. Regul. Toxicol. Pharmacol., 60(1):151–160, 2011. [PubMed]
We use the IUIS nomenclature and allergens in SDAP as the official set of allergens. We also include other proteins clearly marked as non-IUIS allergens as a service for allergen researchers exploring proteins that might have a potential allergenic response.
- PD distance: Download PD Distance Perl Script by Surendra Negi
- List of 1908 allergens and isoallergens: List
- 1628 protein sequences for allergens and isoallergens: List
- 109 allergens with PDB structures: List
- 378 AlphaFold 3D models for allergens: List
- 30 allergens with IgE epitope sets: List
- 233 new Pfam allergen classes: List
- Implementation of the FAO/WHO Allergenicity Test
- FASTA search against all SDAP allergens
- Compute sequence similarity for two sequences using the PD index
- Search with a user-provided peptide for similar regions in all SDAP allergens using the PD similarity index