Sialidase A (nanA) is a 1035-residue protein from Streptococcus pneumoniae (strain ATCC BAA-255 / R6). This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P62576.
Explore in 3D Color by confidence AlphaFold DB UniProt
The mean pLDDT of this model is 81.2 (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 | 72% |
| 70 to 90 | Confident: backbone generally right | 4% |
| 50 to 70 | Low: treat with caution | 1% |
| Below 50 | Very low: often disordered regions | 24% |
What pLDDT means and how to read it
Secreted, cell wall
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 2W20 | X-ray | 1.49 Å | A/B=321-791 |
| 3H71 | X-ray | 1.7 Å | A/B=317-793 |
| 3H72 | X-ray | 1.7 Å | A/B=317-793 |
| 3H73 | X-ray | 1.7 Å | A/B=317-793 |
| 6QZH | X-ray | 2.1 Å | A=322-791, A=796-802 |
MolViewer loads the AlphaFold model straight from AlphaFold DB into your browser. Show it as a cartoon, color by pLDDT, measure distances and angles, and load a PDB structure next to it to compare.