Proteasome subunit alpha type-3 (PRE9) is a 258-residue protein from Saccharomyces cerevisiae (strain ATCC 204508 / S288c). This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P23638.
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The mean pLDDT of this model is 92.9 (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 | 11% |
| 50 to 70 | Low: treat with caution | 2% |
| Below 50 | Very low: often disordered regions | 4% |
What pLDDT means and how to read it
The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity
The 26S proteasome consists of a 20S proteasome core and two 19S regulatory subunits. The 20S proteasome core is composed of 28 subunits that are arranged in four stacked rings, resulting in a barrel-shaped structure. The two end rings are each formed by seven alpha subunits, and the two central rings are each formed by seven beta subunits. The catalytic chamber with the active sites is on the…
Cytoplasm, Nucleus
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 1RYP | X-ray | 1.9 Å | C/Q=2-245 |
| 8RVQ | EM | 2.02 Å | C/Q=1-258 |
| 4R17 | X-ray | 2.1 Å | B/P=1-258 |
| 8RVL | EM | 2.14 Å | C/Q=1-258 |
| 8U7U | EM | 2.16 Å | C/Q=1-258 |
| 1G65 | X-ray | 2.25 Å | B/P=2-245 |
| 8RVP | EM | 2.28 Å | C/Q=1-258 |
| 4QVP | X-ray | 2.3 Å | B/P=1-258 |
| 5CZ4 | X-ray | 2.3 Å | B/P=1-258 |
| 6HWE | X-ray | 2.3 Å | B/P=1-258 |
| 9GBK | EM | 2.39 Å | C/Q=1-258 |
| 1G0U | X-ray | 2.4 Å | B/P=1-245 |
| 3NZJ | X-ray | 2.4 Å | B/P=1-258 |
| 4QLQ | X-ray | 2.4 Å | B/P=1-258 |
| 4R18 | X-ray | 2.4 Å | B/P=1-258 |
| 4Y70 | X-ray | 2.4 Å | B/P=1-258 |
| 4Y7Y | X-ray | 2.4 Å | B/P=1-258 |
| 4Y8L | X-ray | 2.4 Å | B/P=1-258 |
| 5L5A | X-ray | 2.4 Å | B/P=1-258 |
| 8T0M | EM | 2.4 Å | C/Q=1-258 |
Showing 20 of 376 experimental structures (best resolution first).
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