Q08880 (DPO3E_BUCAP) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
DNA polymerase III subunit epsilon
EC=2.7.7.7

Gene names

Name:	dnaQ
Synonyms:	mutD
Ordered Locus Names:	BUsg_240

Organism

Buchnera aphidicola subsp. Schizaphis graminum (strain Sg) [Complete proteome] [HAMAP]

Taxonomic identifier

198804 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Buchnera › Buchnera aphidicola › Buchnera aphidicola (Schizaphis graminum)

Protein attributes

Sequence length	233 AA.
Sequence status	Complete.
Protein existence	Inferred from homology

General annotation (Comments)

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 By similarity.
Catalytic activity	Deoxynucleoside triphosphate + DNA(n) = diphosphate + DNA(n+1).
Cofactor	Binds 2 divalent metal cations. Magnesium or manganese By similarity.
Subunit structure	The DNA polymerase holoenzyme is a complex that contains 10 different types of subunits. These subunits are 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. The polymerase is tethered to the template via the sliding clamp processivity factor. The clamp-loading complex assembles the beta processivity factor onto the primer template and plays a central role in the organization and communication at the replication fork. This complex contains delta, delta', psi and chi, and copies of either or both of two different DnaX proteins, gamma and tau. The composition of the holoenzyme is, therefore: (alpha,epsilon,theta)[2]-(gamma/tau)[3]-delta,delta', psi,chi-beta[4] By similarity.
Sequence caution	The sequence AAM67799.1 differs from that shown. Reason: Erroneous initiation.

Ontologies

Keywords
Biological process	DNA replication
Ligand	Magnesium Manganese Metal-binding
Molecular function	DNA-directed DNA polymerase Exonuclease Hydrolase Nuclease Nucleotidyltransferase Transferase
Technical term	Complete proteome
Gene Ontology (GO)
Biological_process	DNA replication Inferred from electronic annotation. Source: UniProtKB-KW nucleic acid phosphodiester bond hydrolysis Inferred from electronic annotation. Source: GOC
Cellular_component	intracellular Inferred from electronic annotation. Source: InterPro
Molecular_function	DNA binding Inferred from electronic annotation. Source: InterPro DNA-directed DNA polymerase activity Inferred from electronic annotation. Source: UniProtKB-KW exonuclease activity Inferred from electronic annotation. Source: UniProtKB-KW metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 233	233	DNA polymerase III subunit epsilon		PRO_0000105481
Sites
	Active site	161	1	Proton acceptor By similarity
	Metal binding	11	1	Divalent metal cation 1; catalytic By similarity
	Metal binding	11	1	Divalent metal cation 2; catalytic By similarity
	Metal binding	13	1	Divalent metal cation 1; catalytic By similarity
	Metal binding	166	1	Divalent metal cation 1; catalytic By similarity
	Binding site	11	1	Substrate By similarity
	Binding site	13	1	Substrate By similarity
	Binding site	60	1	Substrate By similarity
	Binding site	65	1	Substrate By similarity
	Binding site	166	1	Substrate By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q08880 [UniParc]. Last modified November 1, 1997. Version 2. Checksum: F722E4C65DB1E583	FASTA	233	27,170
	10 20 30 40 50 60 MNNTQRIIVL DTETTGMNSV GPPYLNHRII EIGAIEIINR RFTGKKFHTY IKPNRLIESD 70 80 90 100 110 120 ASKIHGITDD FLSDKPSFKD IAKDFFNYIK NSELIIHNAS FDVGFINQEF SMLTKKIQDI 130 140 150 160 170 180 SNFCNIIDTL KIARKLFPGK KNTLDALCMR YKIKNSHRVL HGAILDAFLL GKLYLLMTSG 190 200 210 220 230 QESIIFNKNI QNERNFRYIK KSITKKHRFL KIIKANKTEL KLHNEYLKFL KEK

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Evolution of dnaQ, the gene encoding the editing 3' to 5' exonuclease subunit of DNA polymerase III holoenzyme in Gram-negative bacteria." Huang Y., Braithwaite D.K., Ito J. FEBS Lett. 400:94-98(1997) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"50 million years of genomic stasis in endosymbiotic bacteria." Tamas I., Klasson L., Canbaeck B., Naeslund A.K., Eriksson A.-S., Wernegreen J.J., Sandstroem J.P., Moran N.A., Andersson S.G.E. Science 296:2376-2379(2002) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: Sg.
[3]	"Buchnera aphidicola (a prokaryotic endosymbiont of aphids) contains a putative 16S rRNA operon unlinked to the 23S rRNA-encoding gene: sequence determination, and promoter and terminator analysis." Munson M.A., Baumann L., Baumann P. Gene 137:171-178(1993) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-179.

Cross-references

Sequence databases
EMBL GenBank DDBJ	U77464 Genomic DNA. Translation: AAC44791.1. AE013218 Genomic DNA. Translation: AAM67799.1. Different initiation. L18927 Genomic DNA. Translation: AAA17435.1.
PIR	I40594.
RefSeq	NP_660588.1. NC_004061.1.
3D structure databases
ProteinModelPortal	Q08880.
SMR	Q08880. Positions 6-178.
ModBase	Search...
Protein-protein interaction databases
STRING	198804.BUsg240.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
EnsemblBacteria	AAM67799; AAM67799; BUsg_240.
GeneID	1005441.
KEGG	bas:BUsg240.
PATRIC	21247281. VBIBucAph100086_0251.
Organism-specific databases
CMR	Search...
Phylogenomic databases
eggNOG	COG0847.
KO	K02342.
OMA	HGITNEF.
ProtClustDB	CLSK315823.
Enzyme and pathway databases
BioCyc	BAPH198804:GHMG-301-MONOMER.
Family and domain databases
InterPro	IPR006054. DnaQ. IPR006309. DnaQ_proteo. IPR006055. Exonuclease. IPR013520. Exonuclease_RNaseT/DNA_pol3. IPR012337. RNaseH-like_dom. [Graphical view]
Pfam	PF00929. RNase_T. 1 hit. [Graphical view]
SMART	SM00479. EXOIII. 1 hit. [Graphical view]
SUPFAM	SSF53098. RNaseH_fold. 1 hit.
TIGRFAMs	TIGR00573. dnaq. 1 hit. TIGR01406. dnaQ_proteo. 1 hit.
ProtoNet	Search...

Entry information

Entry name

DPO3E_BUCAP

Accession

Primary (citable) accession number: Q08880

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1994
Last sequence update:	November 1, 1997
Last modified:	May 1, 2013
This is version 90 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program