O54376 (DPO3B_LACLM) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
DNA polymerase III subunit beta
EC=2.7.7.7

Gene names

Name:	dnaN
Ordered Locus Names:	llmg_0002

Organism

Lactococcus lactis subsp. cremoris (strain MG1363) [Complete proteome] [HAMAP]

Taxonomic identifier

416870 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Firmicutes › Bacilli › Lactobacillales › Streptococcaceae › Lactococcus › Lactococcus lactis › Lactococcus lactis subsp. cremoris

Protein attributes

Sequence length	380 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. This DNA polymerase also exhibits 3' to 5' exonuclease activity. The beta chain is required for initiation of replication once it is clamped onto DNA, it slides freely (bidirectional and ATP-independent) along duplex DNA By similarity.
Catalytic activity	Deoxynucleoside triphosphate + DNA(n) = diphosphate + DNA(n+1).
Subunit structure	DNA polymerase III contains a core (composed of alpha, epsilon and theta chains) that associates with a tau subunit. This core dimerizes to form the POLIII' complex. PolIII' associates with the gamma complex (composed of gamma, delta, delta', psi and chi chains) and with the beta chain to form the complete DNA polymerase III complex By similarity.
Subcellular location	Cytoplasm By similarity.

Ontologies

Keywords
Biological process	DNA replication
Cellular component	Cytoplasm
Molecular function	DNA-directed DNA polymerase Nucleotidyltransferase Transferase
Technical term	Complete proteome
Gene Ontology (GO)
Biological_process	DNA replication Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	DNA polymerase III complex Inferred from electronic annotation. Source: InterPro cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	3'-5' exonuclease activity Inferred from electronic annotation. Source: InterPro DNA binding Inferred from electronic annotation. Source: InterPro DNA-directed DNA polymerase activity 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 – 380	380	DNA polymerase III subunit beta		PRO_0000105441

Sequences

	Sequence		Length	Mass (Da)
	O54376 [UniParc]. Last modified June 1, 1998. Version 1. Checksum: 4877297F3E822644	FASTA	380	42,209
	10 20 30 40 50 60 MIKFSINKTA FQNALKITKQ AIGSKVTIPA LTKLKIEVEE KGITLIGSNG QISIKNFLPA 70 80 90 100 110 120 DNKDASMLIS GTGSVLLEAA FFENVVSQLP EVTLEFIEKE QKQVLLTSGK SEITLKGLDS 130 140 150 160 170 180 EIYPHLQEIS EGSSLKMKVK VLKEIFTETV FAVSTQENRP IFTGVHLETL STGELKAVAT 190 200 210 220 230 240 DSHRMSQRLL PLEDTDLKFD VILPSKSINS FKNVFTNDEE EIEIFISGSQ MLFQNETISY 250 260 270 280 290 300 YSRLIEGSYP DTNRLIPNEA DYTLDLVFDA AQLRHTMDRA RLLTVMTTNG TVKLTVSGDS 310 320 330 340 350 360 VVTTANSPEV GSVHEELTAL SKEGNDLSIS FNPEYLIDAL KVIKAPEVRI RFISNVRPFT 370 380 LQPRNEESGF VQLITPVRTN

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Identification of the lactococcal exonuclease/recombinase and its modulation by the putative Chi sequence." El-Karoui M., Ehrlich S.D., Gruss A. Proc. Natl. Acad. Sci. U.S.A. 95:626-631(1998) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"The complete genome sequence of the lactic acid bacterial paradigm Lactococcus lactis subsp. cremoris MG1363." Wegmann U., O'Connell-Motherway M., Zomer A., Buist G., Shearman C., Canchaya C., Ventura M., Goesmann A., Gasson M.J., Kuipers O.P., van Sinderen D., Kok J. J. Bacteriol. 189:3256-3270(2007) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: MG1363.

Cross-references

Sequence databases
EMBL GenBank DDBJ	U76424 Genomic DNA. Translation: AAC12964.1. AM406671 Genomic DNA. Translation: CAL96610.1.
PIR	T30306.
RefSeq	YP_001031367.1. NC_009004.1.
3D structure databases
ProteinModelPortal	O54376.
SMR	O54376. Positions 1-379.
ModBase	Search...
Protein-protein interaction databases
STRING	416870.llmg_0002.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
EnsemblBacteria	CAL96610; CAL96610; llmg_0002.
GeneID	4798369.
KEGG	llm:llmg_0002.
PATRIC	22280991. VBILacLac4574_0002.
Organism-specific databases
CMR	Search...
Phylogenomic databases
eggNOG	COG0592.
HOGENOM	HOG000071792.
KO	K02338.
OMA	DYNRVIP.
ProtClustDB	PRK05643.
Enzyme and pathway databases
BioCyc	LLAC416870:GCDT-2-MONOMER.
Family and domain databases
InterPro	IPR001001. DNA_polIII_beta. IPR022635. DNA_polIII_beta_C. IPR022637. DNA_polIII_beta_cen. IPR022634. DNA_polIII_beta_N. [Graphical view]
Pfam	PF00712. DNA_pol3_beta. 1 hit. PF02767. DNA_pol3_beta_2. 1 hit. PF02768. DNA_pol3_beta_3. 1 hit. [Graphical view]
PIRSF	PIRSF000804. DNA_pol_III_b. 1 hit.
SMART	SM00480. POL3Bc. 1 hit. [Graphical view]
TIGRFAMs	TIGR00663. dnan. 1 hit.
ProtoNet	Search...

Entry information

Entry name

DPO3B_LACLM

Accession

Primary (citable) accession number: O54376
Secondary accession number(s): A2RH75

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 15, 1998
Last sequence update:	June 1, 1998
Last modified:	May 29, 2013
This is version 75 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program