Immunoglobulin heavy variable 3-33 (IGHV3-33) is a 117-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P01772.
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The mean pLDDT of this model is 90.9 (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 | 83% |
| 70 to 90 | Confident: backbone generally right | 1% |
| 50 to 70 | Low: treat with caution | 15% |
| Below 50 | Very low: often disordered regions | 1% |
What pLDDT means and how to read it
V region of the variable domain of immunoglobulin heavy chains that participates in the antigen recognition (PubMed:24600447). Immunoglobulins, also known as antibodies, are membrane-bound or secreted glycoproteins produced by B lymphocytes. In the recognition phase of humoral immunity, the membrane-bound immunoglobulins serve as receptors which, upon binding of a specific antigen, trigger the clonal expansion and differentiation of B lymphocytes into immunoglobulins-secreting plasma cells. Secreted immunoglobulins mediate the effector phase of humoral immunity, which results in the elimination of bound antigens (PubMed:20176268, PubMed:22158414). The antigen binding site is formed by the…
Immunoglobulins are composed of two identical heavy chains and two identical light chains; disulfide-linked
Secreted, Cell membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 2FB4 | X-ray | 1.9 Å | H=20-117 |
| 7CZT | EM | 2.7 Å | H/I=20-117 |
| 2IG2 | X-ray | 3.0 Å | H=20-117 |
| 2RCJ | X-ray | A/B/E/F/I/J/M/N/Q/R=20-117 |
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