Small ribosomal subunit protein bS21 (rpsU) is a 71-residue protein from Escherichia coli (strain K12). This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P68679.
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The mean pLDDT of this model is 88.2 (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 | 56% |
| 70 to 90 | Confident: backbone generally right | 37% |
| 50 to 70 | Low: treat with caution | 7% |
| Below 50 | Very low: often disordered regions | 0% |
What pLDDT means and how to read it
Probably involved in recognition of ribosome rescue factor SmrB in stalled/collided disomes; fusion of protein fragments to its N-terminus decreases ribosome rescue in the presence of SmrB (PubMed:35264790)
Part of the 30S ribosomal subunit (PubMed:10094780, PubMed:16272117, PubMed:27906160, PubMed:27906161, PubMed:27934701, PubMed:7556101, PubMed:765257). In stalled ribosomes contacts ribosome rescue factor SmrB (PubMed:35264790)
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 8B0X | EM | 1.55 Å | U=1-71 |
| 9Q87 | EM | 1.55 Å | U=1-71 |
| 8CGJ | EM | 1.79 Å | U=1-71 |
| 8FTO | EM | 1.85 Å | U=1-71 |
| 9GHE | EM | 1.87 Å | U=1-71 |
| 8CGU | EM | 1.89 Å | U=1-71 |
| 8AYE | EM | 1.96 Å | U=1-71 |
| 7K00 | EM | 1.98 Å | U=1-71 |
| 8QOA | EM | 2.0 Å | U=1-71 |
| 9FDA | EM | 2.0 Å | U=1-71 |
| 8G6W | EM | 2.02 Å | U=1-71 |
| 8BIL | EM | 2.04 Å | y=1-71 |
| 8BIM | EM | 2.04 Å | y=1-71 |
| 8CEP | EM | 2.04 Å | U=1-71 |
| 8CAI | EM | 2.08 Å | U=1-71 |
| 9H8G | EM | 2.09 Å | U=1-71 |
| 4YBB | X-ray | 2.1 Å | AU/BU=2-57 |
| 8EMM | EM | 2.1 Å | U=1-71 |
| 8BGE | EM | 2.11 Å | y=1-71 |
| 8CGR | EM | 2.12 Å | U=1-71 |
Showing 20 of 502 experimental structures (best resolution first).
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