Proteasome subunit beta type-1 (PSMB1) is a 241-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P20618.
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The mean pLDDT of this model is 91.4 (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 | 88% |
| 70 to 90 | Confident: backbone generally right | 1% |
| 50 to 70 | Low: treat with caution | 3% |
| Below 50 | Very low: often disordered regions | 9% |
What pLDDT means and how to read it
Non-catalytic component of the 20S core proteasome complex involved in the proteolytic degradation of most intracellular proteins. This complex plays numerous essential roles within the cell by associating with different regulatory particles. Associated with two 19S regulatory particles, forms the 26S proteasome and thus participates in the ATP-dependent degradation of ubiquitinated proteins. The 26S proteasome plays a key role in the maintenance of protein homeostasis by removing misfolded or damaged proteins that could impair cellular functions, and by removing proteins whose functions are no longer required. Associated with the PA200 or PA28, the 20S proteasome mediates…
The 26S proteasome consists of a 20S proteasome core and two 19S regulatory subunits (PubMed:25599644, PubMed:26133119, PubMed:27342858, PubMed:27428775, PubMed:27493187, PubMed:34711951). The 20S proteasome core is a barrel-shaped complex made of 28 subunits that are arranged in four stacked rings (PubMed:25599644, PubMed:26133119, PubMed:27342858, PubMed:27428775, PubMed:27493187,…
Cytoplasm, Nucleus
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 5LE5 | X-ray | 1.8 Å | L/Z=29-241 |
| 5LEY | X-ray | 1.9 Å | L/Z=29-241 |
| 5LF4 | X-ray | 1.99 Å | L/Z=29-241 |
| 5LF1 | X-ray | 2.0 Å | L/Z=29-241 |
| 5LF7 | X-ray | 2.0 Å | L/Z=29-241 |
| 8UD9 | EM | 2.04 Å | M/a=29-241 |
| 5LF6 | X-ray | 2.07 Å | L/Z=29-241 |
| 5LF3 | X-ray | 2.1 Å | L/Z=29-241 |
| 8BZL | X-ray | 2.14 Å | L/Z=1-241 |
| 5LEZ | X-ray | 2.19 Å | L/Z=29-241 |
| 5LEX | X-ray | 2.2 Å | L/Z=29-241 |
| 7AWE | X-ray | 2.29 Å | M/a=29-241 |
| 5LF0 | X-ray | 2.41 Å | L/Z=29-241 |
| 7B12 | X-ray | 2.43 Å | 1/M=29-241 |
| 5L5F | X-ray | 2.5 Å | L/Z=126-138 |
| 9K53 | EM | 2.5 Å | S/s=1-241 |
| 9HMN | EM | 2.55 Å | M/W=29-241 |
| 4R3O | X-ray | 2.6 Å | 1/M=29-241 |
| 5L5H | X-ray | 2.6 Å | L/Z=126-138 |
| 5L5O | X-ray | 2.6 Å | L/Z=126-138 |
Showing 20 of 170 experimental structures (best resolution first).
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