Annotations: 6Z6D

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	F_UNCLASSIFIED	e6z6dA1	A: a/b three-layered sandwiches	X: P-loop domains-like	H: P-loop domains-related	T: P-loop containing nucleoside triphosphate hydrolases	F: F_UNCLASSIFIED	ECOD (1.6)
A	F_UNCLASSIFIED	e6z6dA2	A: mixed a+b and a/b	X: Ribonuclease H-like	H: Ribonuclease H-like (From Topology)	T: Ribonuclease H-like	F: F_UNCLASSIFIED	ECOD (1.6)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF20441	Terminase large subunit, endonuclease domain (TerL_nuclease)	Terminase large subunit, endonuclease domain	This is the endonuclease domain of Terminase large subunit TerL [1,2], a key component of the DNA packing machinery in tailed bacteriophages and related viruses. TerL comprises a N-terminal ATPase domain (Pfam:PF03354) which powers the DNA translocat ...	This is the endonuclease domain of Terminase large subunit TerL [1,2], a key component of the DNA packing machinery in tailed bacteriophages and related viruses. TerL comprises a N-terminal ATPase domain (Pfam:PF03354) which powers the DNA translocation and this C-terminal endonuclease domain that cuts concatemeric DNA first in the initiation phase in a sequence specific site and later in the completion stage of the DNA packaging process when the capsid is full [1,2]. Cryo-EM studies indicate that TerL forms a pentamer that binds to a dodecameric assembly called portal and attaches to the capsid. It has been proposed that nuclease domains form a radially arranged ring that is proximal to portal, playing a key role in pentamer assembly [2]. This nuclease domain has a RNAse H-like fold and it has been proposed to utilise a two-metal catalysis mechanism like in other RNAse H-like endonucleases such as RNase H, transposases, retroviral integrases and RuvC Holliday junction resolvases [1].	Domain
A	PF03354	Terminase large subunit, ATPase domain (TerL_ATPase)	Terminase large subunit, ATPase domain	Terminase large subunit (TerL) from bacteriophages and evolutionarily related viruses, is an important component of the DNA packing machinery and comprises an ATPase domain, which powers DNA translocation and a nuclease domain that cuts concatemeric ...	Terminase large subunit (TerL) from bacteriophages and evolutionarily related viruses, is an important component of the DNA packing machinery and comprises an ATPase domain, which powers DNA translocation and a nuclease domain that cuts concatemeric DNA [1,2]. TerL forms pentamers in which the ATPase domains form a ring distal to the capsid. This is the ATPase domain which contains a C-terminal subdomain that sits above the ATPase active site, called the "Lid subdomain" with reference to analogous lid subdomains found in other ATPases [3]. It contains a hydrophobic patch (Trp and Tyr residues) that mediates critical interactions in the interface between adjacent ATPase subunits and assists the positioning of the arginine finger residue that catalyses ATP hydrolysis [2,3]. This entry also includes bacterial proteins of unknown function.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Terminase large subunit	endonuclease activity nuclease activity hydrolase activity, acting on ester bonds hydrolase activity catalytic activity	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR046462	Terminase large subunit-like, endonuclease domain	Domain
A	IPR005021	Terminase large subunit-like	Family
A	IPR027417	P-loop containing nucleoside triphosphate hydrolase	Homologous Superfamily
A	IPR046461	Terminase large subunit-like, ATPase domain	Domain

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.