Hemagglutinin (HA) is a 565-residue protein from Influenza A virus. This is its AlphaFold structure prediction, created 3 Sept 2026. UniProt accession: P03452.
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The mean pLDDT of this model is 77.8 (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 | 40% |
| 70 to 90 | Confident: backbone generally right | 31% |
| 50 to 70 | Low: treat with caution | 18% |
| Below 50 | Very low: often disordered regions | 11% |
What pLDDT means and how to read it
Binds to sialic acid-containing receptors on the cell surface, bringing about the attachment of the virus particle to the cell. This attachment induces virion internalization either through clathrin-dependent endocytosis or through clathrin- and caveolin-independent pathway. Plays a major role in the determination of host range restriction and virulence. Class I viral fusion protein. Responsible for penetration of the virus into the cell cytoplasm by mediating the fusion of the membrane of the endocytosed virus particle with the endosomal membrane. Low pH in endosomes induces an irreversible conformational change in HA2, releasing the fusion hydrophobic peptide. Several trimers are…
Homotrimer of disulfide-linked HA1-HA2. Interacts with human CACNA1C (PubMed:29779930)
Virion membrane, Host apical cell membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 9PHD | X-ray | 1.59 Å | C=18-343, D=344-519 |
| 5VLI | X-ray | 1.8 Å | A=17-343, B=344-519 |
| 9PHS | X-ray | 2.02 Å | A/C/E=18-343, B/D/F=344-519 |
| 8VQQ | X-ray | 2.05 Å | A=18-338, B=344-565 |
| 1RVX | X-ray | 2.2 Å | A/C/E/G/I/K=14-338, B/D/F/H/J/L=344-503 |
| 8VQM | X-ray | 2.21 Å | A=18-339, B=344-565 |
| 8VQN | X-ray | 2.21 Å | A=18-339, B=344-565 |
| 1RVZ | X-ray | 2.25 Å | A/C/E/G/I/K=14-338, B/D/F/H/J/L=344-503 |
| 5W5S | X-ray | 2.28 Å | A=18-343, B=344-519 |
| 8VQL | X-ray | 2.29 Å | A=18-339, B=344-565 |
| 1RU7 | X-ray | 2.3 Å | A/C/E/G/I/K=18-338, B/D/F/H/J/L=344-503 |
| 9PIB | X-ray | 2.35 Å | A/C/E/G=18-343, B/D/F/H=344-519 |
| 9DXX | X-ray | 2.37 Å | A=18-343, B=344-519 |
| 5W5U | X-ray | 2.46 Å | A=18-343, B=344-519 |
| 5W6T | X-ray | 2.59 Å | A=18-343, B=344-519 |
| 6WCR | X-ray | 2.68 Å | A=18-343, B=344-519 |
| 5W6R | X-ray | 2.73 Å | A/C/E/G=18-343, B/D/F/H=344-519 |
| 8SD2 | X-ray | 2.81 Å | A=18-343, B=344-519 |
| 9PHQ | X-ray | 2.87 Å | A=18-343, B=344-519 |
| 5W6U | X-ray | 2.88 Å | A=18-343, B=344-519 |
Showing 20 of 23 experimental structures (best resolution first).
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