P03007 · DPO3E_ECOLI
- ProteinDNA polymerase III subunit epsilon
- GenednaQ
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids243 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. The epsilon subunit contain the editing function and is a proofreading 3'-5' exonuclease (PubMed:6340117).
Contacts both the beta sliding clamp (dnaN) and the polymerase subunit (dnaE), stabilizing their interaction (PubMed:26499492).
Contacts both the beta sliding clamp (dnaN) and the polymerase subunit (dnaE), stabilizing their interaction (PubMed:26499492).
Catalytic activity
- a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1)
Cofactor
Mn2+ (UniProtKB | Rhea| CHEBI:29035 )
Note: Binds 2 divalent metal cations. Magnesium or manganese.
Features
Showing features for binding site, active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 12 | a divalent metal cation 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 12 | a divalent metal cation 2 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 12 | substrate | ||||
Sequence: D | ||||||
Binding site | 14 | a divalent metal cation 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: E | ||||||
Binding site | 14 | substrate | ||||
Sequence: E | ||||||
Binding site | 61 | substrate | ||||
Sequence: E | ||||||
Binding site | 66 | substrate | ||||
Sequence: H | ||||||
Active site | 162 | Proton acceptor | ||||
Sequence: H | ||||||
Binding site | 167 | a divalent metal cation 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 167 | substrate | ||||
Sequence: D |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytosol | |
Cellular Component | DNA polymerase III complex | |
Cellular Component | DNA polymerase III, core complex | |
Cellular Component | replisome | |
Molecular Function | 3'-5' exonuclease activity | |
Molecular Function | DNA binding | |
Molecular Function | DNA-directed DNA polymerase activity | |
Molecular Function | exonuclease activity | |
Molecular Function | metal ion binding | |
Biological Process | DNA replication proofreading | |
Biological Process | DNA-templated DNA replication | |
Biological Process | lagging strand elongation | |
Biological Process | leading strand elongation |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameDNA polymerase III subunit epsilon
- EC number
Gene names
Organism names
- Organism
- Strains
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Escherichia
Accessions
- Primary accessionP03007
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Phenotypes & Variants
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 15 | In mutD5, reduces suppression of AZT sensitivity of holC or yoaA knockouts, reduces exonuclease activity. | ||||
Sequence: T → I | ||||||
Mutagenesis | 183-187 | Increases binding to beta sliding clamp (dnaN), increases stability of enzyme complex. | ||||
Sequence: TSMAF → LSLPL |
Chemistry
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000105483 | 1-243 | DNA polymerase III subunit epsilon | |||
Sequence: MSTAITRQIVLDTETTGMNQIGAHYEGHKIIEIGAVEVVNRRLTGNNFHVYLKPDRLVDPEAFGVHGIADEFLLDKPTFAEVADEFMDYIRGAELVIHNAAFDIGFMDYEFSLLKRDIPKTNTFCKVTDSLAVARKMFPGKRNSLDALCARYEIDNSKRTLHGALLDAQILAEVYLAMTGGQTSMAFAMEGETQQQQGEATIQRIVRQASKLRVVFATDEEIAAHEARLDLVQKKGGSCLWRA |
Proteomic databases
Interaction
Subunit
In a ternary complex this subunit contacts both the beta sliding clamp (dnaN) and the polymerase subunit (dnaE) (PubMed:26499492).
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:6340117).
The polymerase is tethered to the template via the dimeric beta sliding clamp processivity factor. The clamp loader (also called gamma complex) assembles the beta sliding clamp onto the primed template and plays a central role in the organization and communication at the replication fork. The clamp-loading complex contains delta, delta', psi and chi, and 3 copies of either or both of two different DnaX proteins, gamma and tau. The DNA replisome complex has a single clamp loader (3 tau and 1 each of delta, delta', psi and chi subunits) which binds 3 Pol III cores (1 core on the leading strand and 2 on the lagging strand) each with a beta sliding clamp dimer. Additional proteins in the replisome are other copies of gamma, psi and chi, Ssb, DNA helicase and RNA primase (PubMed:20413500, PubMed:22157955).
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:6340117).
The polymerase is tethered to the template via the dimeric beta sliding clamp processivity factor. The clamp loader (also called gamma complex) assembles the beta sliding clamp onto the primed template and plays a central role in the organization and communication at the replication fork. The clamp-loading complex contains delta, delta', psi and chi, and 3 copies of either or both of two different DnaX proteins, gamma and tau. The DNA replisome complex has a single clamp loader (3 tau and 1 each of delta, delta', psi and chi subunits) which binds 3 Pol III cores (1 core on the leading strand and 2 on the lagging strand) each with a beta sliding clamp dimer. Additional proteins in the replisome are other copies of gamma, psi and chi, Ssb, DNA helicase and RNA primase (PubMed:20413500, PubMed:22157955).
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | P03007 | dnaE P10443 | 25 | EBI-549131, EBI-549111 | |
BINARY | P03007 | dnaN P0A988 | 6 | EBI-549131, EBI-542385 | |
BINARY | P03007 | dnaX P06710 | 6 | EBI-549131, EBI-549140 | |
BINARY | P03007 | holA P28630 | 3 | EBI-549131, EBI-549153 | |
BINARY | P03007 | holE P0ABS8 | 13 | EBI-549131, EBI-549182 |
Protein-protein interaction databases
Structure
Sequence
- Sequence statusComplete
- Length243
- Mass (Da)27,099
- Last updated1988-04-01 v1
- Checksum4211C9A00744964F
Sequence caution
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
X04027 EMBL· GenBank· DDBJ | CAA27661.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
K00985 EMBL· GenBank· DDBJ | AAA24564.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U70214 EMBL· GenBank· DDBJ | AAB08637.1 EMBL· GenBank· DDBJ | Genomic DNA | Different initiation | |
U00096 EMBL· GenBank· DDBJ | AAC73320.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AP009048 EMBL· GenBank· DDBJ | BAA77886.1 EMBL· GenBank· DDBJ | Genomic DNA |