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HAMAP rule MF_04145

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General rule information [?]

Accession MF_04145
Dates 17-JAN-2020 (Created)
1-JUN-2023 (Last updated, Version 9)
Scope(s) Viruses
Template(s) P54308 (TERL_BPSPP); [ Recover all ]
Triggered by HAMAP; MF_04145 (Get profile general information and statistics)

Propagated annotation [?]

Identifier, protein and gene names [?]

Identifier TERL
Protein name RecName: Full=Terminase, large subunit;
AltName: Full=DNA-packaging protein;
RecName: Full=Endonuclease;
RecName: Full=ATPase;

Comments [?]

FUNCTIONThe 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 adapter and the stopper protein that form the connector.
case <FTGroup:1>
COFACTOR Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Note=Binds 2 divalent metal cations per subunit. Mn(2+) is preferred over Mg(2+).;
end case
SUBUNITMonomer. Interacts with the terminase small subunit; the active complex is probably heterooligomeric. Interacts with the portal protein.
DOMAINThe N-terminus contains an ATPase domain and the C-terminus contains an endonuclease domain.

Keywords [?]

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

Cross-references [?]

Pfam PF04466; Terminase_3; 1;
Pfam PF17288; Terminase_3C; 1;
NCBIfam TIGR01547; phage_term_2; 1;

Features [?]

From: TERL_BPSPP (P54308)
Key From To Description Tag Condition FTGroup
REGION 1 198 /note="ATPase activity"
REGION 232 422 /note="Nuclease activity and binding to the portal protein"
MOTIF 33 40 /note="Walker A motif" G-[GS]-[AR]-[AG]-S-[AGK]-[AGK]-S
MOTIF 130 135 /note="Walker B motif" x-[CAGLM]-W-[IFY]-E-E
ACT_SITE 135 135 /note="For ATPase activity" E
BINDING 266 266 /ligand="Mn(2+)"
/ligand_note="catalytic; for nuclease activity"
D 1
BINDING 266 266 /ligand="Mn(2+)"
/ligand_note="catalytic; for nuclease activity"
D 1
BINDING 321 321 /ligand="Mn(2+)"
/ligand_note="catalytic; for nuclease activity"
D 1
BINDING 400 400 /ligand="Mn(2+)"
/ligand_note="catalytic; for nuclease activity"
H 1
BINDING 403 403 /ligand="Mn(2+)"
/ligand_note="catalytic; for nuclease activity"
D 1

Additional information [?]

Size range 370-540 amino acids
Related rules None
Fusion Nter: None Cter: None

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