1RDD

CRYSTAL STRUCTURE OF ESCHERICHIA COLI RNASE HI IN COMPLEX WITH MG2+ AT 2.8 ANGSTROMS RESOLUTION: PROOF FOR A SINGLE MG2+ SITE

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Structure Motif: Primary M-CSA Annotation

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1rdda_	Alpha and beta proteins (a/b)	Ribonuclease H-like motif	Ribonuclease H-like	Ribonuclease H	RNase H (RNase HI)	(Escherichia coli ) [TaxId: 562 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Ribonuclease H-like	8043698	3000143	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	RNase_H	e1rddA1	A: mixed a+b and a/b	X: Ribonuclease H-like	H: Ribonuclease H-like (From Topology)	T: Ribonuclease H-like	F: RNase_H	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.30.420.10	Alpha Beta	2-Layer Sandwich	Nucleotidyltransferase	domain 5	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF00075	RNase H (RNase_H)	RNase H	RNase H digests the RNA strand of an RNA/DNA hybrid. Important enzyme in retroviral replication cycle, and often found as a domain associated with reverse transcriptases. Structure is a mixed alpha+beta fold with three a/b/a layers.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	RIBONUCLEASE H	cation binding magnesium ion binding ion binding binding metal ion binding small molecule binding endonuclease activity RNA endonuclease activity, producing 5'-phosphomonoesters catalytic activity, acting on RNA RNA-DNA hybrid ribonuclease activity catalytic activity, acting on a nucleic acid RNA nuclease activity hydrolase activity nuclease activity cation binding magnesium ion binding ion binding binding metal ion binding small molecule binding endonuclease activity RNA endonuclease activity, producing 5'-phosphomonoesters catalytic activity, acting on RNA RNA-DNA hybrid ribonuclease activity catalytic activity, acting on a nucleic acid RNA nuclease activity hydrolase activity nuclease activity hydrolase activity, acting on ester bonds RNA endonuclease activity endonuclease activity, active with either ribo- or deoxyribonucleic acids and producing 5'-phosphomonoesters catalytic activity organic cyclic compound binding nucleic acid binding	DNA replication, removal of RNA primer catabolic process RNA metabolic process primary metabolic process DNA metabolic process nucleic acid metabolic process macromolecule catabolic process organic cyclic compound catabolic process nucleobase-containing compound catabolic process nucleobase-containing compound metabolic process organic cyclic compound metabolic process DNA replication organic substance metabolic process nucleic acid catabolic process DNA replication, removal of RNA primer catabolic process RNA metabolic process primary metabolic process DNA metabolic process nucleic acid metabolic process macromolecule catabolic process organic cyclic compound catabolic process nucleobase-containing compound catabolic process nucleobase-containing compound metabolic process organic cyclic compound metabolic process DNA replication organic substance metabolic process nucleic acid catabolic process metabolic process macromolecule metabolic process organic substance catabolic process RNA catabolic process	intracellular anatomical structure cytoplasm cellular anatomical entity

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR036397	Ribonuclease H superfamily	Homologous Superfamily
A	IPR022892	Ribonuclease HI	Family
A	IPR002156	Ribonuclease H domain	Domain
A	IPR012337	Ribonuclease H-like superfamily	Homologous Superfamily

Structure Motif Annotation: Mechanism and Catalytic Site Atlas M-CSA Database Homepage

Chains	Enzyme Name	Description	Catalytic Residues
A	ribonuclease HI M-CSA #163	Members of the RNase H family hydrolyze the P-O3' bond of the RNA strand of an RNA-DNA hybrid duplex in the presence of divalent cations such as Mg(II) and Mn(II). RNase HI is found in Escherichia coli and is structurally homologous to the RNase H domain of HIV-1 reverse transcriptase, a target for anti-HIV therapy. Two alternative mechanisms have been proposed for this enzyme. One is a two-metal-ion mechanism where one of the two metal ions activates the attacking hydroxide ion and the other is a general acid-base mechanism where an amino acid residue fulfils this role. Computational studies seem to favour the two metal ion proposal, however NMR and kinetic studies suggest only one metal binds to this protein and that the protein is inactivated by subsequent metal binding events.	Defined by 6 residues: ASP:A-10GLY:A-11GLU:A-48ASP:A-70HIS:A-124ASP:A-134 \| Explore in 3D: M-CSA Motif Definition Search M-CSA Motif EC: 3.1.26.4 (PDB Primary Data) Search M-CSA Motif + EC 3.1.26.4

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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 R01GM133198.