DNA polymerase III subunit chi (holC) is a 147-residue protein from Escherichia coli (strain K12). This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P28905.
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The mean pLDDT of this model is 95.9 (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 | 93% |
| 70 to 90 | Confident: backbone generally right | 8% |
| 50 to 70 | Low: treat with caution | 0% |
| Below 50 | Very low: often disordered regions | 0% |
What pLDDT means and how to read it
Part of the beta sliding clamp loading complex, which hydrolyzes ATP to load the beta clamp onto primed DNA to form the DNA replication pre-initiation complex (PubMed:2040637). DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. Genetically identified as involved in the repair of replication forks and tolerance of the chain-terminating nucleoside analog 3' AZT (PubMed:26544712, PubMed:33582602, PubMed:34181484). This subunit may stabilize YoaA and/or stimulate the helicase activity of YoaA (PubMed:36509145)
The DNA polymerase III holoenzyme complex contains at least 10 different subunits organized into 3 functionally essential subassemblies: the Pol III core, the beta sliding clamp processivity factor and the clamp-loading complex. The Pol III core (subunits alpha, epsilon and theta) contains the polymerase and the 3'-5' exonuclease proofreading activities (PubMed:2040637). The polymerase is…
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