1ORO

A FLEXIBLE LOOP AT THE DIMER INTERFACE IS A PART OF THE ACTIVE SITE OF THE ADJACENT MONOMER OF ESCHERICHIA COLI OROTATE PHOSPHORIBOSYLTRANSFERASE

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	d1oroa_	Alpha and beta proteins (a/b)	PRTase-like	PRTase-like	Phosphoribosyltransferases (PRTases)	Orotate PRTase	(Escherichia coli ) [TaxId: 562 ],	SCOPe (2.08)
B	d1orob_	Alpha and beta proteins (a/b)	PRTase-like	PRTase-like	Phosphoribosyltransferases (PRTases)	Orotate PRTase	(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	SCOP2 Family	Phosphoribosyltransferases (PRTases)	8019860	4000253	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	PRTase-like	8032240	3000060	SCOP2 (2022-06-29)
B	SCOP2B Superfamily	PRTase-like	8032240	3000060	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	PF00156	e1oroA1	A: a/b three-layered sandwiches	X: PRTase-like (From Topology)	H: PRTase-like (From Topology)	T: PRTase-like	F: PF00156	ECOD (1.6)
B	PF00156	e1oroB1	A: a/b three-layered sandwiches	X: PRTase-like (From Topology)	H: PRTase-like (From Topology)	T: PRTase-like	F: PF00156	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.40.50.2020	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold		CATH (4.3.0)
B	3.40.50.2020	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold		CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF00156	Phosphoribosyl transferase domain (Pribosyltran)	Phosphoribosyl transferase domain	This family includes a range of diverse phosphoribosyl transferase enzymes. This family includes: Adenine phosphoribosyl-transferase EC:2.4.2.7, Swiss:P07672. Hypoxanthine-guanine-xanthine phosphoribosyl-transferase Swiss:P51900. Hypoxanthine phosph ...	This family includes a range of diverse phosphoribosyl transferase enzymes. This family includes: Adenine phosphoribosyl-transferase EC:2.4.2.7, Swiss:P07672. Hypoxanthine-guanine-xanthine phosphoribosyl-transferase Swiss:P51900. Hypoxanthine phosphoribosyl-transferase EC:2.4.2.8 Swiss:P36766. Ribose-phosphate pyrophosphokinase i EC:2.7.6.1 Swiss:P09329. Amidophosphoribosyltransferase EC:2.4.2.14 Swiss:P00496. Orotate phosphoribosyl-transferase EC:2.4.2.10 Swiss:P11172. Uracil phosphoribosyl-transferase EC:2.4.2.9 Swiss:P25532. Xanthine-guanine phosphoribosyl-transferase EC:2.4.2.22 Swiss:P00501. In Arabidopsis, At the very N-terminus of this domain is the P-Loop NTPase domain [1].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	OROTATE PHOSPHORIBOSYLTRANSFERASE	cation binding magnesium ion binding ion binding binding metal ion binding small molecule binding identical protein binding protein binding protein homodimerization activity protein dimerization activity pentosyltransferase activity glycosyltransferase activity transferase activity orotate phosphoribosyltransferase activity cation binding magnesium ion binding ion binding binding metal ion binding small molecule binding identical protein binding protein binding protein homodimerization activity protein dimerization activity pentosyltransferase activity glycosyltransferase activity transferase activity orotate phosphoribosyltransferase activity catalytic activity	nucleotide biosynthetic process organonitrogen compound biosynthetic process pyrimidine nucleotide metabolic process nucleobase-containing compound metabolic process organic substance metabolic process nucleobase-containing small molecule metabolic process organic substance biosynthetic process phosphate-containing compound metabolic process small molecule metabolic process pyrimidine-containing compound biosynthetic process phosphorus metabolic process nucleoside phosphate metabolic process pyrimidine-containing compound metabolic process organonitrogen compound metabolic process nucleotide biosynthetic process organonitrogen compound biosynthetic process pyrimidine nucleotide metabolic process nucleobase-containing compound metabolic process organic substance metabolic process nucleobase-containing small molecule metabolic process organic substance biosynthetic process phosphate-containing compound metabolic process small molecule metabolic process pyrimidine-containing compound biosynthetic process phosphorus metabolic process nucleoside phosphate metabolic process pyrimidine-containing compound metabolic process organonitrogen compound metabolic process cellular metabolic process primary metabolic process nucleobase-containing compound biosynthetic process nucleotide metabolic process organic cyclic compound metabolic process biosynthetic process organophosphate metabolic process organophosphate biosynthetic process organic cyclic compound biosynthetic process nucleoside phosphate biosynthetic process metabolic process cellular process pyrimidine nucleotide biosynthetic process glycosyl compound metabolic process carbohydrate derivative metabolic process nucleoside biosynthetic process pyrimidine nucleoside metabolic process carbohydrate derivative biosynthetic process glycosyl compound biosynthetic process small molecule biosynthetic process ribonucleoside biosynthetic process nucleoside metabolic process nucleobase-containing small molecule biosynthetic process pyrimidine ribonucleoside metabolic process pyrimidine ribonucleoside biosynthetic process pyrimidine nucleoside biosynthetic process ribonucleoside metabolic process nucleobase biosynthetic process pyrimidine nucleobase biosynthetic process pyrimidine nucleobase metabolic process nucleobase metabolic process 'de novo' pyrimidine nucleobase biosynthetic process ribose phosphate metabolic process 'de novo' UMP biosynthetic process ribonucleotide biosynthetic process UMP biosynthetic process ribonucleotide metabolic process ribonucleoside monophosphate metabolic process UMP metabolic process nucleoside monophosphate metabolic process ribose phosphate biosynthetic process pyrimidine ribonucleotide metabolic process pyrimidine nucleoside monophosphate metabolic process pyrimidine ribonucleoside monophosphate metabolic process nucleoside monophosphate biosynthetic process pyrimidine ribonucleoside monophosphate biosynthetic process pyrimidine nucleoside monophosphate biosynthetic process ribonucleoside monophosphate biosynthetic process pyrimidine ribonucleotide biosynthetic process	intracellular anatomical structure cytoplasm cellular anatomical entity cytosol

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR000836	Phosphoribosyltransferase domain	Domain
A, B	IPR004467	Orotate phosphoribosyl transferase domain	Domain
A, B	IPR023031	Orotate phosphoribosyltransferase	Family
A, B	IPR029057	Phosphoribosyltransferase-like	Homologous Superfamily

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

Chains	Enzyme Name	Description	Catalytic Residues
A	orotate phosphoribosyltransferase M-CSA #873	Orotate phosphoribosyltransferase (OPRTase) is involved in the biosynthesis of pyrimidine nucleotides. In the pyrimidine synthesis pathway, OPRT catalyses the reversible phosphoribosyl transfer from 5'-phospho-alpha-D-ribose 1'-diphosphate (PRPP) to orotic acid (OA), forming pyrophosphate and orotidine 5'-monophosphate (OMP). The mechanism of PRTases has been the subject of much debate over the years. However, stereochemical results argue against mechanisms which invoke a covalent enzyme-phosphoribosyl intermediate. Kinetic studies argue against a direct SN2-type displacement. Thus, a two-step, SN1-type mechanisms with oxocarbonium-like transition states or intermediates has been proposed as the most likely mechanism. However, there is still much debate as to the exact roles of the residues involved.	Defined by 2 residues: LYS:A-103HIS:A-105 \| Explore in 3D: M-CSA Motif Definition Search M-CSA Motif EC: 2.4.2.10 (PDB Primary Data) Search M-CSA Motif + EC 2.4.2.10

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.