P14565 · TRAI1_ECOLI
- ProteinMultifunctional conjugation protein TraI
- GenetraI
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids1756 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Conjugative DNA transfer (CDT) is the unidirectional transfer of ssDNA plasmid from a donor to a recipient cell. It is the central mechanism by which antibiotic resistance and virulence factors are propagated in bacterial populations. Part of the relaxosome, which facilitates a site- and strand-specific cut in the origin of transfer by TraI, at the nic site. Relaxosome formation requires binding of IHF and TraY to the oriT region, which then facilitates binding of TraI relaxase. TraI forms a covalent 5'-phosphotyrosine intermediate linkage to the ssDNA. The transesterified T-strand moves from the donor cell to the recipient cell in a 5'to 3' direction, with the DNA helicase activity of TraI unwinding the DNA. DNA transfer occurs via the conjugative pore (transferosome) an intercellular junction mediated by a type IV secretion system, with TraD providing the means to link the relaxosome to the conjugative pore. The relaxase completes DNA transfer by reversing the covalent phosphotyrosine linkage and releasing the T-strand.
TraI has also been identified as DNA helicase I. DNA. helicase I is a potent, highly processive DNA-dependent ATPase, able to unwind about 1.1 kb dsDNA per second in a 5' to 3' manner.
Catalytic activity
- ATP + H2O = ADP + H+ + phosphate
Cofactor
Activity regulation
Nicking activity (relaxase) is inhibited by bisphosphonates such as the non-competitive inhibitor imidobisphosphate (PNP), etidronic acid (ETIDRO) and clodronic acid (CLODRO). The latter 2 are competitive inhibitors, and are already used clinically to treat bone loss (marketed as Didronel and Bonefos). All 3 compounds also inhibit conjugation and kill F plasmid-containing cells. They are specific to dual tyrosine relaxases such as those found in F and related R conjugative plasmids.
Features
Showing features for active site, binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Active site | 16 | O-(5'-phospho-DNA)-tyrosine intermediate; for relaxase activity | ||||
Sequence: Y | ||||||
Active site | 17 | Relaxase | ||||
Sequence: Y | ||||||
Binding site | 146 | Mg2+ (UniProtKB | ChEBI); catalytic | ||||
Sequence: H | ||||||
Binding site | 157 | Mg2+ (UniProtKB | ChEBI); catalytic | ||||
Sequence: H | ||||||
Binding site | 159 | Mg2+ (UniProtKB | ChEBI); catalytic | ||||
Sequence: H | ||||||
Binding site | 992-999 | ATP (UniProtKB | ChEBI) | ||||
Sequence: GYAGVGKT |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytoplasm | |
Molecular Function | ATP binding | |
Molecular Function | ATP hydrolysis activity | |
Molecular Function | DNA binding | |
Molecular Function | DNA helicase activity | |
Molecular Function | DNA topoisomerase type I (single strand cut, ATP-independent) activity | |
Molecular Function | metal ion binding |
Keywords
- Molecular function
- Biological process
- Ligand
Names & Taxonomy
Protein names
- Recommended nameMultifunctional conjugation protein TraI
Including 2 domains:
- Recommended nameDNA relaxase TraI
- EC number
- Alternative names
- Recommended nameDNA helicase I
- EC number
Gene names
Encoded on
- Plasmid F
Organism names
- Organism
- Strains
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Escherichia
Accessions
- Primary accessionP14565
- Secondary accessions
Subcellular Location
Phenotypes & Variants
Disruption phenotype
Loss of conjugative DNA transfer.
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 1 | Loss of ssDNA binding. | ||||
Sequence: Missing | ||||||
Mutagenesis | 3 | 1000-fold reduced affinity for ssDNA. | ||||
Sequence: S → A | ||||||
Mutagenesis | 16 | Loss of DNA nicking ability; still binds ssDNA. | ||||
Sequence: Y → F | ||||||
Mutagenesis | 17 | Loss of DNA nicking ability; still binds ssDNA. | ||||
Sequence: Y → F | ||||||
Mutagenesis | 23 | Reduced DNA nicking ability. | ||||
Sequence: Y → F | ||||||
Mutagenesis | 24 | Reduced DNA nicking ability. | ||||
Sequence: Y → F | ||||||
Mutagenesis | 88 | 10000-fold reduced affinity for ssDNA. | ||||
Sequence: K → A | ||||||
Mutagenesis | 159 | Loss of oriT cleavage. | ||||
Sequence: H → E | ||||||
Mutagenesis | 237 | 300-fold reduced affinity for ssDNA. | ||||
Sequence: R → A | ||||||
Mutagenesis | 241 | 1500-fold reduced affinity for ssDNA. | ||||
Sequence: I → A | ||||||
Mutagenesis | 998 | No helicase activity, nicks DNA, loss of DNA transfer activity. | ||||
Sequence: K → M | ||||||
Mutagenesis | 1517-1525 | 10,000-fold reduction in conjugative DNA transfer. | ||||
Sequence: Missing | ||||||
Mutagenesis | 1518-1525 | 100,000-fold reduction in conjugative DNA transfer. | ||||
Sequence: PGRKYPQP → GGRKYGQG | ||||||
Mutagenesis | 1574-1575 | 200-fold reduction in conjugative DNA transfer; when associated with A-1603. | ||||
Sequence: LQ → AA | ||||||
Mutagenesis | 1603 | 200-fold reduction in conjugative DNA transfer; when associated with 1574-A-A-1575. | ||||
Sequence: V → A | ||||||
Mutagenesis | 1721-1756 | More than 100-fold reduction in conjugative DNA transfer. | ||||
Sequence: Missing |
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000024504 | 1-1756 | Multifunctional conjugation protein TraI | |||
Sequence: MMSIAQVRSAGSAGNYYTDKDNYYVLGSMGERWAGRGAEQLGLQGSVDKDVFTRLLEGRLPDGADLSRMQDGSNRHRPGYDLTFSAPKSVSMMAMLGGDKRLIDAHNQAVDFAVRQVEALASTRVMTDGQSETVLTGNLVMALFNHDTSRDQEPQLHTHAVVANVTQHNGEWKTLSSDKVGKTGFIENVYANQIAFGRLYREKLKEQVEALGYETEVVGKHGMWEMPGVPVEAFSGRSQTIREAVGEDASLKSRDVAALDTRKSKQHVDPEIKMAEWMQTLKETGFDIRAYRDAADQRADLRTLTPGPASQDGPDVQQAVTQAIAGLSERKVQFTYTDVLARTVGILPPENGVIERARAGIDEAISREQLIPLDREKGLFTSGIHVLDELSVRALSRDIMKQNRVTVHPEKSVPRTAGYSDAVSVLAQDRPSLAIVSGQGGAAGQRERVAELVMMAREQGREVQIIAADRRSQMNMKQDERLSGELITGRRQLLEGMAFTPGSTVIVDQGEKLSLKETLTLLDGAARHNVQVLITDSGQRTGTGSALMAMKDAGVNTYRWQGGEQRPATIISEPDRNVRYARLAGDFAASVKAGEESVAQVSGVREQAILTQAIRSELKTQGVLGLPEVTMTALSPVWLDSRSRYLRDMYRPGMVMEQWNPETRSHDRYVIDRVTAQSHSLTLRDAQGETQVVRISSLDSSWSLFRPEKMPVADGERLRVTGKIPGLRVSGGDRLQVASVSEDAMTVVVPGRAEPATLPVSDSPFTALKLENGWVETPGHSVSDSATVFASVTQMAMDNATLNGLARSGRDVRLYSSLDETRTAEKLARHPSFTVVSEQIKTRAGETSLETAISHQKSALHTPAQQAIHLALPVVESKKLAFSMVDLLTEAKSFAAEGTGFTELGGEINAQIKRGDLLYVDVAKGYGTGLLVSRASYEAEKSILRHILEGKEAVMPLMERVPGELMEKLTSGQRAATRMILETSDRFTVVQGYAGVGKTTQFRAVMSAVNMLPESERPRVVGLGPTHRAVGEMRSAGVDAQTLASFLHDTQLQQRSGETPDFSNTLFLLDESSMVGNTDMARAYALIAAGGGRAVASGDTDQLQAIAPGQPFRLQQTRSAADVAIMKEIVRQTPELREAVYSLINRDVERALSGLESVKPSQVPRQEGAWAPEHSVTEFSHSQEAKLAEAQQKAMLKGEAFPDVPMTLYEAIVRDYTGRTPEAREQTLIVTHLNEDRRVLNSMIHDVREKAGELGKEQVMVPVLNTANIRDGELRRLSTWETHRDALVLVDNVYHRIAGISKDDGLITLQDAEGNTRLISPREAVAEGVTLYTPDTIRVGTGDRMRFTKSDRERGYVANSVWTVTAVSGDSVTLSDGQQTREIRPGQEQAEQHIDLAYAITAHGAQGASETFAIALEGTEGNRKLMAGFESAYVALSRMKQHVQVYTDNRQGWTDAINNAVQKGTAHDVFEPKPDREVMNAERLFSTARELRDVAAGRAVLRQAGLAGGDSPARFIAPGRKYPQPYVALPAFDRNGKSAGIWLNPLTTDDGNGLRGFSGEGRVKGSGDAQFVALQGSRNGESLLADNMQDGVRIARDNPDSGVVVRIAGEGRPWNPGAITGGRVWGDIPDNSVQPGAGNGEPVTAEVLAQRQAEEAIRRETERRADEIVRKMAENKPDLPDGKTEQAVREIAGQERDRAAITEREAALPEGVLREPQRVREAVREIARENLLQERLQQMERDMVRDLQKEKTLGGD |
Interaction
Subunit
Monomer. Part of the relaxosome, a complex composed of plasmid-encodes TraI, TraM, TraY and host-encoded IHF bound to the F plasmid origin of transfer (oriT). Directly contacts coupling protein TraD. Seems to directly contact TraM via its C-terminus.
Structure
Family & Domains
Features
Showing features for region, coiled coil.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 1-330 | DNA relaxase | ||||
Sequence: MMSIAQVRSAGSAGNYYTDKDNYYVLGSMGERWAGRGAEQLGLQGSVDKDVFTRLLEGRLPDGADLSRMQDGSNRHRPGYDLTFSAPKSVSMMAMLGGDKRLIDAHNQAVDFAVRQVEALASTRVMTDGQSETVLTGNLVMALFNHDTSRDQEPQLHTHAVVANVTQHNGEWKTLSSDKVGKTGFIENVYANQIAFGRLYREKLKEQVEALGYETEVVGKHGMWEMPGVPVEAFSGRSQTIREAVGEDASLKSRDVAALDTRKSKQHVDPEIKMAEWMQTLKETGFDIRAYRDAADQRADLRTLTPGPASQDGPDVQQAVTQAIAGLSER | ||||||
Region | 950-1500 | DNA helicase I | ||||
Sequence: GKEAVMPLMERVPGELMEKLTSGQRAATRMILETSDRFTVVQGYAGVGKTTQFRAVMSAVNMLPESERPRVVGLGPTHRAVGEMRSAGVDAQTLASFLHDTQLQQRSGETPDFSNTLFLLDESSMVGNTDMARAYALIAAGGGRAVASGDTDQLQAIAPGQPFRLQQTRSAADVAIMKEIVRQTPELREAVYSLINRDVERALSGLESVKPSQVPRQEGAWAPEHSVTEFSHSQEAKLAEAQQKAMLKGEAFPDVPMTLYEAIVRDYTGRTPEAREQTLIVTHLNEDRRVLNSMIHDVREKAGELGKEQVMVPVLNTANIRDGELRRLSTWETHRDALVLVDNVYHRIAGISKDDGLITLQDAEGNTRLISPREAVAEGVTLYTPDTIRVGTGDRMRFTKSDRERGYVANSVWTVTAVSGDSVTLSDGQQTREIRPGQEQAEQHIDLAYAITAHGAQGASETFAIALEGTEGNRKLMAGFESAYVALSRMKQHVQVYTDNRQGWTDAINNAVQKGTAHDVFEPKPDREVMNAERLFSTARELRDVAAGRAV | ||||||
Region | 1534-1756 | Required for DNA transfer, may interact with TraM | ||||
Sequence: RNGKSAGIWLNPLTTDDGNGLRGFSGEGRVKGSGDAQFVALQGSRNGESLLADNMQDGVRIARDNPDSGVVVRIAGEGRPWNPGAITGGRVWGDIPDNSVQPGAGNGEPVTAEVLAQRQAEEAIRRETERRADEIVRKMAENKPDLPDGKTEQAVREIAGQERDRAAITEREAALPEGVLREPQRVREAVREIARENLLQERLQQMERDMVRDLQKEKTLGGD | ||||||
Coiled coil | 1717-1753 | |||||
Sequence: QRVREAVREIARENLLQERLQQMERDMVRDLQKEKTL |
Domain
Has 4 domains; the relaxase domain (residues 1-330), an unknown domain (residues 330-990), the helicase domain (residues 990-1450) and the C-terminal domain (1450-1756) which is required for conjugative DNA transfer, possibly via interaction with TraM.
Sequence similarities
To TraI of plasmid IncFII R100.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence & Isoform
- Sequence statusComplete
This entry describes 2 isoforms produced by Alternative initiation.
P14565-1
This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
- NametraI
- Length1,756
- Mass (Da)192,016
- Last updated1990-11-01 v2
- ChecksumAA07D61DB2BFD9FA
P14565-2
- NametraI*
- Differences from canonical
- 1-954: Missing
Sequence caution
Features
Showing features for alternative sequence, sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Alternative sequence | VSP_018971 | 1-954 | in isoform traI* | |||
Sequence: Missing | ||||||
Sequence conflict | 69-74 | in Ref. 4; AAA83930 | ||||
Sequence: MQDGSN → CRMAVT |
Keywords
- Coding sequence diversity
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
M54796 EMBL· GenBank· DDBJ | AAA98085.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
M54796 EMBL· GenBank· DDBJ | AAA98086.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U01159 EMBL· GenBank· DDBJ | AAC44186.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AP001918 EMBL· GenBank· DDBJ | BAA97974.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
M29254 EMBL· GenBank· DDBJ | AAA83930.1 EMBL· GenBank· DDBJ | Genomic DNA | Different initiation | |
X57430 EMBL· GenBank· DDBJ | CAA40677.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U01159 EMBL· GenBank· DDBJ | AAC44187.1 EMBL· GenBank· DDBJ | Genomic DNA |