Table 1.
Examples of wheat-derived peptide sequences identified in human urine.
| Wheat peptide sequencea | Uniprot protein accession(s)b | Protein name(s) | Mass (Da) | # of participants with peptide |
|---|---|---|---|---|
| GQQQPFPPQQPYPQPQPFPS | GDA0_WHEAT; GDA1_WHEAT; GDA2_WHEAT; GDA9_WHEAT | α/β-gliadin; α-gliadin | 2292.0962 | 8 |
| GQQQPFPPQQPYPQPQPFP | GDA0_WHEAT; GDA1_WHEAT; GDA2_WHEAT; GDA9_WHEAT | α/β-gliadin; α-gliadin | 2205.0642 | 7 |
| SQQPEQTISQQPQQPFPQQPHQPQQPYPQQQPYGSSL | A0A290XYU3_WHEAT; U5UA46_WHEAT; R9XT67_WHEAT; R9XUY1_WHEAT | ω-gliadin | 4284.0259 | 6 |
| SCHVMQQQCC | GDB1_WHEAT; GLTC_WHEAT; GDB3_WHEAT; GLTB_WHEAT | γ-gliadin; LMW glutenin | 1336.4781 | 6 |
| LGQQQPFPPQQPYPQPQPFPSQQP | GDA1_WHEAT; A0A0K2QJX_WHEAT; A0A0E3Z7F7_WHEAT, A0A1K0JNE4_WHEAT | α/β-gliadin; α-gliadin | 2758.3500 | 5 |
| SQQPQQPFPQQPHQPQQPYPQ | B6ETR9_WHEAT; A0A290XYU3_WHEAT; U5UA46_WHEAT; R9XT67_WHEAT | ω-gliadin; LMW glutenin | 2512.1882 | 5 |
| SCHVMQQQCCQ | GDB1_WHEAT; GLTC_WHEAT; GDB3_WHEAT; GLTB_WHEAT | γ-gliadin; LMW glutenin | 1464.5367 | 5 |
| PyrQTFPHQPQQQVPQPQQPQQP | GDB2_WHEAT; B6DQB5_WHEAT; R9XWD0_WHEAT; R9XUB9_WHEAT | γ-gliadin | 2348.1296 | 5 |
| PQQPPFSQQQQQQQQQQQPPFSQQQQPVL | Q5MFQ2_WHEAT; D0EVP4_WHEAT; Q5MFQ1_WHEAT; Q5MFQ6_WHEAT | LMW glutenin | 3457.6763 | 3 |
| TQQPQQPFPQQPQQPFPQQPQQPFPQ | R9XUS6_WHEAT; A0A290XZ20_WHEAT; A0A290XZ51_WHEAT; A0A290XZ34_WHEAT | γ-gliadin | 3098.4998 | 3 |
| TQQPQQPFPQQPQQPFPQTQQPQQPFPQ | GDB2_WHEAT; B6DQB5_WHEAT, R9XV87_WHEAT; R9XWD0_WHEAT | γ-gliadin | 3327.6060 | 3 |
| QPFPPQQPYPQPQPFP | GDA0_WHEAT; GDA1_WHEAT; GDA2_WHEAT; GDA9_WHEAT | α/β-gliadin; α-gliadin | 1891.9257 | 2 |
| P[I/L]QPQQPFPQQPQQPFPQPQc | B6ETR9_WHEAT; A0A290XYW6_WHEAT; R9XT67_WHEAT; R9XUY1_WHEAT | ω-gliadin | 2354.1807 | 2 |
| FLQPQQPFPQQPQQPYPQQPQQPFPQ | GDB0_WHEAT, R9XV78_WHEAT; Q9FS77_WHEAT, B6UKM8_WHEAT | γ-gliadin | 3145.5410 | 1 |
| CHVMQQQCCQd | GDB1_WHEAT; GLTC_WHEAT; GDB3_WHEAT; GLTB_WHEAT | γ-gliadin; LMW glutenin | 1393.5000 | 1 |
| PyrQQQQPPFSQQPPISQQQQPPFSQQQQPQF | GLTA_WHEAT, D2DII3_WHEAT, Q6SPZ1_WHEAT, Q6SPZ3_WHEAT | LMW glutenin | 3416.6174 | 1 |
aResidues in bold indicate CeD-relevant T-cell epitopes, as defined in ref. 37. All Cys residues were detected in their carbamidomethylated forms due to derivatization with iodoacetamide during sample workup. “PyrQ” indicates glutamine residues that had undergone cyclization into pyroglutamic acid.
bFor peptides mapping to more than four proteins in the UniProt database, only the first four accession codes are displayed. All identified peptide sequences and full details relating to peptide identification in each participants’ urine are provided in Supplementary Datasets 3 and 4.
cThe UniProt database contained otherwise identical peptides containing Leu and Ile at the same position. These two amino acids are isobaric and indistinguishable by our MS/MS method and thus the sequence is reported as [I/L].
dThe Met in this peptide was detected in its oxidized form.