A0A2Z5WK49 · A0A2Z5WK49_9CAUD
- ProteinTerminase, large subunit
- Gene17_1
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids523 (go to sequence)
- Protein existenceInferred from homology
- Annotation score3/5
Function
function
The terminase large subunit acts as an ATP driven molecular motor necessary for viral DNA translocation into empty capsids and as an endonuclease that cuts the viral genome to initiate and to end a packaging reaction. The terminase lies at a unique vertex of the procapsid and is composed of two subunits, a small terminase subunit involved in viral DNA recognition (packaging sequence), and a large terminase subunit possessing endonucleolytic and ATPase activities. Both terminase subunits heterooligomerize and are docked on the portal protein to form the packaging machine. The terminase large subunit exhibits endonuclease activity and cleaves the viral genome concatemer once the capsid is full (headful packaging). Once the capsid is packaged with the DNA, the terminase complex is substituted by the tail.
Cofactor
Note: ATPase activity requires 1 Mg2+ ion per subunit. Nuclease activity probably requires 2 Mg2+ ions per subunit.
Activity regulation
Stimulated up to 50 to 100-fold by the terminase small subunit.
Features
Showing features for binding site, active site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 51 | ATP (UniProtKB | ChEBI) | ||||
Sequence: Q | ||||||
Binding site | 56 | ATP (UniProtKB | ChEBI) | ||||
Sequence: Q | ||||||
Binding site | 115 | ATP (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Active site | 169 | For ATPase activity | ||||
Sequence: E | ||||||
Binding site | 314 | Mg2+ 2 (UniProtKB | ChEBI); catalytic; for nuclease activity | ||||
Sequence: D | ||||||
Binding site | 314 | Mg2+ 1 (UniProtKB | ChEBI); catalytic; for nuclease activity | ||||
Sequence: D | ||||||
Site | 322 | Modulates nuclease activity | ||||
Sequence: D | ||||||
Binding site | 371 | Mg2+ 2 (UniProtKB | ChEBI); catalytic; for nuclease activity | ||||
Sequence: E | ||||||
Binding site | 455 | Mg2+ 1 (UniProtKB | ChEBI); catalytic; for nuclease activity | ||||
Sequence: D |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | viral terminase, large subunit | |
Molecular Function | ATP binding | |
Molecular Function | ATP hydrolysis activity | |
Molecular Function | endonuclease activity | |
Molecular Function | metal ion binding | |
Biological Process | chromosome organization | |
Biological Process | viral DNA genome packaging |
Keywords
- Molecular function
- Biological process
- Ligand
Names & Taxonomy
Protein names
- Recommended nameTerminase, large subunit
- Alternative names
Including 2 domains:
- Recommended nameATPase
- EC number
- Recommended nameEndonuclease
- EC number
Gene names
Organism names
- Organism
- Taxonomic lineageViruses > Duplodnaviria > Heunggongvirae > Uroviricota > Caudoviricetes > Straboviridae > Tevenvirinae > Tequatrovirus > Tequatrovirus pp01
Accessions
- Primary accessionA0A2Z5WK49
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Interaction
Subunit
Interacts with the terminase small subunit; the active complex is composed of a pentamer of terminase large subunits and a dodecamer of terminase small subunits. Interacts with the portal protein.
Structure
Family & Domains
Features
Showing features for region, motif, domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 44-214 | ATPase activity | ||||
Sequence: DYGVIKVQLRDYQRDMLKIMSSKRMTVCNLSRQLGKTTVVAIFLAHFVCFNKDKAVGILAHKGSMSAEVLDRTKQAIELLPDFLQPGIVEWNKGSIELDNGSSIGAYASSPDAVRGNSFAMIYIDECAFIPNFHDSWLAIQPVISSGRRSKIIITTTPNGLNHFYDIWTAA | ||||||
Motif | 74-80 | Walker A motif | ||||
Sequence: SRQLGKT | ||||||
Motif | 164-169 | Walker B motif | ||||
Sequence: MIYIDE | ||||||
Motif | 198-200 | ATPase coupling | ||||
Sequence: TTT | ||||||
Region | 273-472 | Nuclease activity | ||||
Sequence: SGTLISGMKLAVMDFIEVTPDDHGFHRFKSPEPDRKYIATLDCSEGRGQDYHALHIIDVTDDVWEQVGVLHSNTISHLILPDIVMRYLVEYNECPVYIELNSTGVSVAKSLYMDLEYEGVICDSYTDLGMKQTKRTKAVGCSTLKDLIEKDKLIIHHRATIQEFRTFSEKGVSWAAEEGYHDDLVMSLVIFGWLSTQSKF | ||||||
Domain | 312-485 | Terminase large subunit gp17-like C-terminal | ||||
Sequence: TLDCSEGRGQDYHALHIIDVTDDVWEQVGVLHSNTISHLILPDIVMRYLVEYNECPVYIELNSTGVSVAKSLYMDLEYEGVICDSYTDLGMKQTKRTKAVGCSTLKDLIEKDKLIIHHRATIQEFRTFSEKGVSWAAEEGYHDDLVMSLVIFGWLSTQSKFIDYADKDDMRLAS |
Domain
The N-terminus contains an ATPase domain. The C-terminus contains an endonuclease domain.
Sequence similarities
Belongs to the Tequatrovirus large terminase family.
Family and domain databases
Sequence
- Sequence statusComplete
- Length523
- Mass (Da)59,283
- Last updated2018-10-10 v1
- Checksum4F2E0AC805F3944E