Beta-2-microglobulin (B2M) is a 118-residue protein from Sus scrofa. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: Q07717.
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The mean pLDDT of this model is 93.7 (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 | 80% |
| 70 to 90 | Confident: backbone generally right | 15% |
| 50 to 70 | Low: treat with caution | 5% |
| Below 50 | Very low: often disordered regions | 0% |
What pLDDT means and how to read it
Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system (By similarity)
Heterodimer of an alpha chain and a beta chain. Beta-2-microglobulin is the beta-chain of major histocompatibility complex class I molecules (By similarity)
Secreted
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 5NQ0 | X-ray | 1.1 Å | B=21-118 |
| 5NPZ | X-ray | 1.43 Å | B=21-118 |
| 5H94 | X-ray | 1.48 Å | B/E=21-118 |
| 5NQ2 | X-ray | 1.54 Å | B=21-118 |
| 9M01 | X-ray | 1.56 Å | B=21-118 |
| 7EMD | X-ray | 1.7 Å | B=21-118 |
| 6KWL | X-ray | 1.8 Å | B=21-118 |
| 6KWO | X-ray | 1.8 Å | B=22-118 |
| 7EMA | X-ray | 1.8 Å | B=21-118 |
| 7EM9 | X-ray | 1.9 Å | B=21-118 |
| 7EMC | X-ray | 1.9 Å | B/E/H=21-118 |
| 7EMB | X-ray | 1.97 Å | B=21-118 |
| 8W6L | X-ray | 2.03 Å | B=21-118 |
| 3QQ4 | X-ray | 2.1 Å | B=21-118 |
| 5YLX | X-ray | 2.2 Å | B=21-118 |
| 8JV0 | X-ray | 2.2 Å | B/E=21-118 |
| 6A6H | X-ray | 2.31 Å | B=21-118 |
| 9UL1 | X-ray | 2.32 Å | B=22-118 |
| 6KWN | X-ray | 2.4 Å | B=21-118 |
| 8GQV | X-ray | 2.4 Å | B/E=21-118 |
Showing 20 of 25 experimental structures (best resolution first).
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