Tryptase alpha/beta-1 (TPSAB1) is a 275-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: Q15661.
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The mean pLDDT of this model is 91.3 (very high overall). pLDDT is AlphaFold's per-residue confidence score from 0 to 100. In MolViewer, choose the B-factor color scheme to color the model by pLDDT, because AlphaFold stores it in the B-factor column.
| pLDDT band | Meaning | Share of residues |
|---|---|---|
| Above 90 | Very high: backbone and side chains are usually accurate | 85% |
| 70 to 90 | Confident: backbone generally right | 3% |
| 50 to 70 | Low: treat with caution | 6% |
| Below 50 | Very low: often disordered regions | 6% |
What pLDDT means and how to read it
Tryptase is the major neutral protease present in mast cells and is secreted upon the coupled activation-degranulation response of this cell type. May play a role in innate immunity. Isoform 2 cleaves large substrates, such as fibronectin, more efficiently than isoform 1, but seems less efficient toward small substrates (PubMed:18854315)
Homotetramer. The active tetramer is converted to inactive monomers at neutral and acidic pH in the absence of heparin. Low concentrations of inactive monomers become active monomers at pH 6.0 in the presence of heparin. When the concentration of active monomers is higher, they convert to active monomers and then to active tetramers. These monomers are active and functionally distinct from the…
Secreted
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 2F9N | X-ray | 1.6 Å | A/B/C/D=31-275 |
| 4MPU | X-ray | 1.65 Å | A/B=31-275 |
| 5F03 | X-ray | 1.94 Å | A/B=31-275 |
| 4MPW | X-ray | 1.95 Å | A/B=31-275 |
| 4MPX | X-ray | 2.0 Å | A/B=31-275 |
| 4A6L | X-ray | 2.05 Å | A/B/C/D=31-275 |
| 2ZEC | X-ray | 2.06 Å | A/B/C/D=31-273 |
| 2F9O | X-ray | 2.1 Å | A/B/C/D=31-275 |
| 6O1F | X-ray | 2.15 Å | A=31-275 |
| 1LTO | X-ray | 2.2 Å | A/B/C/D=31-275 |
| 4MQA | X-ray | 2.25 Å | A/B=31-275 |
| 2F9P | X-ray | 2.3 Å | A/B/C/D=31-275 |
| 4MPV | X-ray | 2.31 Å | A/B=31-275 |
| 8VGK | EM | 2.4 Å | A/B/C/D=31-275 |
| 2ZEB | X-ray | 2.5 Å | A/B/C/D=31-273 |
| 8VGJ | EM | 2.5 Å | A/B/C/D=31-275 |
| 6P0P | X-ray | 2.55 Å | A/B=1-275 |
| 8VGI | EM | 2.7 Å | A/B/C/D=31-275 |
| 5WI6 | X-ray | 2.72 Å | A/B/C/D=31-275 |
| 8VGH | EM | 2.9 Å | A/B/C/D=31-275 |
Showing 20 of 22 experimental structures (best resolution first).
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