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HAMAP rule MF_04147

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General rule information [?]

Accession MF_04147
Dates 7-FEB-2020 (Created)
19-NOV-2022 (Last updated, Version 6)
Name TERL_T7
Viruses; Caudoviricetes
Templates P03694 (TERL_BPT7); P10310 (TERL_BPT3): [Recover all]

Propagated annotation [?]

Identifier, protein and gene names [?]

Protein name
RecName: Full=Terminase, large subunit;
AltName: Full=DNA-packaging protein;
RecName: Full=ATPase;
EC 3.6.4.-;
RecName: Full=Endonuclease;
EC 3.1.21.-;

Comments [?]

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 at a unique and precise dsDNA sequence 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 DNA is packaged, the terminase detaches from the portal and gets replaced by the tail to finish maturation of the virion.
Cofactor Mg(2+)
Subunit Homopentamer. Interacts with the terminase small subunit; the active complex is probably heterooligomeric. Interacts with the portal protein.
Domain The ATPase region is in the N-terminus, whereas the nuclease region is in the central part. The C-terminus is involved in prohead binding.
Similarity Belongs to the Teseptimavirus large terminase family.

Keywords [?]

case <FTGroup:1>
end case

Gene Ontology [?]

GO:0098009; Cellular component: viral terminase, large subunit.
GO:0004519; Molecular function: endonuclease activity.
GO:0046872; Molecular function: metal ion binding.
GO:0004518; Molecular function: nuclease activity.
GO:0051276; Biological process: chromosome organization.
GO:0019073; Biological process: viral DNA genome packaging.

Features [?]

From: TERL_BPT7 (P03694)
Key     From     To       Description   Tag   Condition   FTGroup
REGION     1     229       ATPase activity        
REGION     344     429       Nuclease activity        
REGION     571     586       Involved in prohead binding        
MOTIF     58     65       Walker A motif     [AG]-F-R-G-[AIV]-[AG]-K-[ST]  
MOTIF     156     161       Walker B motif     [ILV]-[ILM]-[ILV]-[AF]-D-D  
BINDING     364     364       /ligand="Mg(2+)" /ligand_id="ChEBI:CHEBI:18420" /ligand_label="1" /ligand_note="catalytic; for nuclease activity     D   1
BINDING     364     364       /ligand="Mg(2+)" /ligand_id="ChEBI:CHEBI:18420" /ligand_label="2" /ligand_note="catalytic; for nuclease activity     D   1
BINDING     420     420       /ligand="Mg(2+)" /ligand_id="ChEBI:CHEBI:18420" /ligand_label="2" /ligand_note="catalytic; for nuclease activity     E   1
BINDING     518     518       /ligand="Mg(2+)" /ligand_id="ChEBI:CHEBI:18420" /ligand_label="1" /ligand_note="catalytic; for nuclease activity     D   1

Additional information [?]

Size range 500-680 amino acids
Related rules None
Fusion None