HLA class I histocompatibility antigen, B alpha chain (HLA-B) is a 362-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P01889.
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The mean pLDDT of this model is 88.1 (confident 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 | 78% |
| 70 to 90 | Confident: backbone generally right | 6% |
| 50 to 70 | Low: treat with caution | 5% |
| Below 50 | Very low: often disordered regions | 12% |
What pLDDT means and how to read it
Antigen-presenting major histocompatibility complex class I (MHCI) molecule. In complex with B2M/beta 2 microglobulin displays primarily viral and tumor-derived peptides on antigen-presenting cells for recognition by alpha-beta T cell receptor (TCR) on HLA-B-restricted CD8-positive T cells, guiding antigen-specific T cell immune response to eliminate infected or transformed cells (PubMed:23209413, PubMed:25808313, PubMed:29531227, PubMed:9620674). May also present self-peptides derived from the signal sequence of secreted or membrane proteins, although T cells specific for these peptides are usually inactivated to prevent autoreactivity (PubMed:18991276, PubMed:7743181). Both the peptide…
Heterotrimer that consists of an alpha chain HLA-B, a beta chain B2M and a peptide (peptide-HLA-B-B2M) (PubMed:15657948, PubMed:17057332, PubMed:22020283, PubMed:24600035, PubMed:25808313, PubMed:29531227). Early in biogenesis, HLA-B-B2M dimer interacts with the components of the peptide-loading complex composed of TAPBP, TAP1-TAP2, TAPBPL, PDIA3/ERP57 and CALR (PubMed:26416272, PubMed:26439010,…
Cell membrane, Endoplasmic reticulum membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 1K5N | X-ray | 1.09 Å | A=25-300 |
| 4U1M | X-ray | 1.18 Å | A=25-301 |
| 3CZF | X-ray | 1.2 Å | A=25-300 |
| 6MT3 | X-ray | 1.21 Å | A=25-300 |
| 3BWA | X-ray | 1.3 Å | A=25-300 |
| 3LN4 | X-ray | 1.3 Å | A=25-298 |
| 3SPV | X-ray | 1.3 Å | A=25-300 |
| 6MT6 | X-ray | 1.31 Å | A=25-300 |
| 2BVP | X-ray | 1.35 Å | A=25-300 |
| 6MTL | X-ray | 1.35 Å | A=25-300 |
| 4U1J | X-ray | 1.38 Å | A=25-301 |
| 6PYW | X-ray | 1.38 Å | A=25-300 |
| 2A83 | X-ray | 1.4 Å | A=25-300 |
| 4QRS | X-ray | 1.4 Å | A=25-300 |
| 4QRT | X-ray | 1.4 Å | A=25-300 |
| 5WMQ | X-ray | 1.4 Å | A=25-300 |
| 6P2C | X-ray | 1.4 Å | A=25-300 |
| 4XXC | X-ray | 1.43 Å | A=25-303 |
| 5IB2 | X-ray | 1.44 Å | A=25-300 |
| 6PYJ | X-ray | 1.44 Å | A=25-300 |
Showing 20 of 237 experimental structures (best resolution first).
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