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Protein

DNA topoisomerase 1

Gene

topA

Organism
Bacillus halodurans (strain ATCC BAA-125 / DSM 18197 / FERM 7344 / JCM 9153 / C-125)
Status
Reviewed-Annotation score: -Protein inferred from homologyi

Functioni

Releases the supercoiling and torsional tension of DNA, which is introduced during the DNA replication and transcription, by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-OH DNA strand. The free DNA strand then undergoes passage around the unbroken strand, thus removing DNA supercoils. Finally, in the religation step, the DNA 3'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone.UniRule annotation

Catalytic activityi

ATP-independent breakage of single-stranded DNA, followed by passage and rejoining.UniRule annotation

Cofactori

Mg2+UniRule annotationNote: Binds two Mg2+ per subunit.UniRule annotation

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Metal bindingi9Magnesium 1; catalyticUniRule annotation1
Metal bindingi82Magnesium 1; catalyticUniRule annotation1
Metal bindingi82Magnesium 2UniRule annotation1
Metal bindingi84Magnesium 2UniRule annotation1
Active sitei298O-(5'-phospho-DNA)-tyrosine intermediateUniRule annotation1

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri579 – 605C4-type 1Add BLAST27
Zinc fingeri619 – 647C4-type 2Add BLAST29
Zinc fingeri660 – 683C4-type 3Add BLAST24

GO - Molecular functioni

GO - Biological processi

Keywordsi

Molecular functionDNA-binding, Isomerase, Topoisomerase
LigandMagnesium, Metal-binding, Zinc

Names & Taxonomyi

Protein namesi
Recommended name:
DNA topoisomerase 1UniRule annotation (EC:5.99.1.2UniRule annotation)
Alternative name(s):
DNA topoisomerase IUniRule annotation
Omega-protein
Relaxing enzyme
Swivelase
Untwisting enzyme
Gene namesi
Name:topAUniRule annotation
Ordered Locus Names:BH2467
OrganismiBacillus halodurans (strain ATCC BAA-125 / DSM 18197 / FERM 7344 / JCM 9153 / C-125)
Taxonomic identifieri272558 [NCBI]
Taxonomic lineageiBacteriaFirmicutesBacilliBacillalesBacillaceaeBacillus
Proteomesi
  • UP000001258 Componenti: Chromosome

Subcellular locationi

GO - Cellular componenti

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00001451411 – 690DNA topoisomerase 1Add BLAST690

Proteomic databases

PRIDEiQ9KA23

Interactioni

Subunit structurei

Monomer.UniRule annotation

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sitei33Interaction with DNAUniRule annotation1
Sitei139Interaction with DNAUniRule annotation1
Sitei140Interaction with DNAUniRule annotation1
Sitei143Interaction with DNAUniRule annotation1
Sitei148Interaction with DNAUniRule annotation1
Sitei155Interaction with DNAUniRule annotation1
Sitei300Interaction with DNAUniRule annotation1
Sitei490Interaction with DNAUniRule annotation1

Protein-protein interaction databases

STRINGi272558.BH2467

Structurei

3D structure databases

ProteinModelPortaliQ9KA23
SMRiQ9KA23
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini3 – 121ToprimUniRule annotationAdd BLAST119

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni163 – 168Interaction with DNAUniRule annotation6

Sequence similaritiesi

Belongs to the type IA topoisomerase family.UniRule annotation

Zinc finger

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri579 – 605C4-type 1Add BLAST27
Zinc fingeri619 – 647C4-type 2Add BLAST29
Zinc fingeri660 – 683C4-type 3Add BLAST24

Keywords - Domaini

Repeat, Zinc-finger

Phylogenomic databases

eggNOGiENOG4105C73 Bacteria
COG0550 LUCA
COG0551 LUCA
HOGENOMiHOG000004018
KOiK03168
OMAiPECKYTR
OrthoDBiPOG091H02BN

Family and domain databases

CDDicd00186 TOP1Ac, 1 hit
cd03363 TOPRIM_TopoIA_TopoI, 1 hit
Gene3Di1.10.290.10, 1 hit
1.10.460.10, 2 hits
2.70.20.10, 2 hits
HAMAPiMF_00952 Topoisom_1_prok, 1 hit
InterProiView protein in InterPro
IPR000380 Topo_IA
IPR003601 Topo_IA_2
IPR023406 Topo_IA_AS
IPR013497 Topo_IA_cen
IPR013824 Topo_IA_cen_sub1
IPR013825 Topo_IA_cen_sub2
IPR013826 Topo_IA_cen_sub3
IPR023405 Topo_IA_core_domain
IPR003602 Topo_IA_DNA-bd_dom
IPR013498 Topo_IA_Znf
IPR005733 TopoI_bac-type
IPR028612 Topoisom_1_IA
IPR006171 TOPRIM_domain
IPR034149 TOPRIM_TopoI
PANTHERiPTHR42785 PTHR42785, 1 hit
PfamiView protein in Pfam
PF01131 Topoisom_bac, 1 hit
PF01751 Toprim, 1 hit
PF01396 zf-C4_Topoisom, 3 hits
PRINTSiPR00417 PRTPISMRASEI
SMARTiView protein in SMART
SM00437 TOP1Ac, 1 hit
SM00436 TOP1Bc, 1 hit
SM00493 TOPRIM, 1 hit
SUPFAMiSSF56712 SSF56712, 1 hit
TIGRFAMsiTIGR01051 topA_bact, 1 hit
PROSITEiView protein in PROSITE
PS00396 TOPOISOMERASE_I_PROK, 1 hit
PS50880 TOPRIM, 1 hit

Sequencei

Sequence statusi: Complete.

Q9KA23-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MADYLVIVES PAKAKTIGKY LGKKYTVKAS MGHVRDLPKS QMGVDIEDEY
60 70 80 90 100
SPRYITIRGK GPVLKELKSA AKKVKRVYLA ADPDREGEAI AWHLAHSLDI
110 120 130 140 150
DETSECRVVF NEITKQAIKD AFKSPRPINM DLVDAQQARR VLDRLVGYNI
160 170 180 190 200
SPLLWKKVKK GLSAGRVQSV AVKMIIDREK EIQAFEPEEY WSIQGTFALD
210 220 230 240 250
GEPFEAKFYG TNGKKVELKS EDDVNNVLAK LKGDQFHVDS VQKKERKRNP
260 270 280 290 300
VSPFTTSSLQ QEAARKLNFR AKKTMMLAQQ LYEGIDLGKE GTVGLITYMR
310 320 330 340 350
TDSTRISDTA KAETKEYIES KFGKEYAQNG TKAVKKDKKS QDAHEAIRPT
360 370 380 390 400
SVERDPKSLK EYLSRDQLRL YKLIWERLVA SQMAPAIMDT MTVDLSNEGV
410 420 430 440 450
LFRATGSKVK FPGFMKVYIE GNDEGKKEED RLLPNLQEGQ TVTKEEIEPS
460 470 480 490 500
QHFTQPPPRY TEARLVKTME ELGIGRPSTY APTLDTIQKR GYVALDERRF
510 520 530 540 550
VPTELGEIVL ELMTEFFPEI LDVEFTAKME DDLDSIEEGK QQWIKIIDDF
560 570 580 590 600
YKGFEERLKV AEEEMKEVEI KDEPTGEMCE KCGHEMVYKM GRYGKFMACS
610 620 630 640 650
NFPDCRNTKP IVKEIGVKCP KCEKGEIVER KSKKRRVFYG CNQYPECDFV
660 670 680 690
SWDKPIARSC PKCSSYLVEK RTKKQVQVQC SSCDYKEEAN
Length:690
Mass (Da):78,911
Last modified:October 1, 2000 - v1
Checksum:iEE3E9EE0B5546256
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
BA000004 Genomic DNA Translation: BAB06186.1
PIRiC83958
RefSeqiWP_010898620.1, NC_002570.2

Genome annotation databases

EnsemblBacteriaiBAB06186; BAB06186; BAB06186
KEGGibha:BH2467

Similar proteinsi

Entry informationi

Entry nameiTOP1_BACHD
AccessioniPrimary (citable) accession number: Q9KA23
Entry historyiIntegrated into UniProtKB/Swiss-Prot: December 1, 2000
Last sequence update: October 1, 2000
Last modified: May 23, 2018
This is version 121 of the entry and version 1 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

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