Dihydroorotase

Class of enzymes

carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase

Dihydroorotase (fragment) dimer, Human

Identifiers

Symbol

CAD

NCBI gene

790

HGNC

1424

OMIM

114010

RefSeq

NM_004341

UniProt

P27708

Other data

EC number

3.5.2.3

Locus

Chr. 2 p22-p21

Search for
Structures	Swiss-model
Domains	InterPro

Dihydroorotase (EC 3.5.2.3, carbamoylaspartic dehydrase, dihydroorotate hydrolase) is an enzyme which converts carbamoyl aspartic acid into 4,5-dihydroorotic acid in the biosynthesis of pyrimidines.^[1]^[2] It forms a multifunctional enzyme with carbamoyl phosphate synthetase and aspartate transcarbamoylase. Dihydroorotase is a zinc metalloenzyme.^[3]

References

^ Cooper C, Wilson DW (1954). "Biosynthesis of pyrimidines". Fed. Proc. 13: 194.
^ Lieberman I, Kornberg A (April 1954). "Enzymatic synthesis and breakdown of a pyrimidine, orotic acid. I. Dihydroortic acid, ureidosuccinic acid, and 5-carboxymethylhydantoin" (PDF). The Journal of Biological Chemistry. 207 (2): 911–24. doi:10.1016/S0021-9258(18)65708-4. PMID 13163076.
^ Voet, Donald (2011). Biochemistry. Judith G. Voet. Hoboken, NJ: John Wiley & Sons. ISBN 978-0-470-57095-1. OCLC 690489261.

External links

Dihydroorotase at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
EC 3.5.2.3

Metabolism: amino acid metabolism
nucleotide enzymes

Purine metabolism

Anabolism

R5P→IMP:	Ribose-phosphate diphosphokinase Amidophosphoribosyltransferase Phosphoribosylglycinamide formyltransferase AIR synthetase (FGAM cyclase) Phosphoribosylaminoimidazole carboxylase Phosphoribosylaminoimidazolesuccinocarboxamide synthase IMP synthase
IMP→AMP:	Adenylosuccinate synthase Adenylosuccinate lyase reverse AMP deaminase
IMP→GMP:	IMP dehydrogenase GMP synthase reverse GMP reductase

Nucleotide salvage

Catabolism

Pyrimidine metabolism

Anabolism

CAD Carbamoyl phosphate synthase II Aspartate carbamoyltransferase Dihydroorotase
Dihydroorotate dehydrogenase Orotidine 5'-phosphate decarboxylase/Uridine monophosphate synthetase
CTP synthetase

Catabolism

Deoxyribonucleotides

v t e Enzymes: multienzyme complexes
Photosynthesis	Photosynthetic reaction center complex proteins Photosystem I II
Dehydrogenase	Pyruvate dehydrogenase complex E1 E2 E3 Oxoglutarate dehydrogenase OGDH DLST DLD Branched-chain alpha-keto acid dehydrogenase complex BCKDHA BCKDHB DBT DLD
Other	CAD Carbamoyl phosphate synthase II Aspartate carbamoyltransferase Dihydroorotase P450-containing systems Cytochrome b6f complex Electron transport chain Fatty acid synthetase complex Glycine decarboxylase complex Mitochondrial trifunctional protein HADHA HADHB Phosphoenolpyruvate sugar phosphotransferase system Polyketide synthase Sucrase-isomaltase complex Tryptophan synthase

v t e Hydrolases: carbon-nitrogen non-peptide (EC 3.5)
3.5.1: Linear amides / Amidohydrolases	Asparaginase Glutaminase Urease Biotinidase Aminoacylase ACY1 Aspartoacylase(ACY2) ACY3 Ceramidase Aspartylglucosaminidase Fatty acid amide hydrolase Histone deacetylase Sirtuin
3.5.2: Cyclic amides/ Amidohydrolases	Barbiturase Beta-lactamase Dihydroorotase
3.5.3: Linear amidines/ Ureohydrolases	Arginase Agmatinase Protein-arginine deiminase
3.5.4: Cyclic amidines/ Aminohydrolases	Guanine deaminase Adenosine deaminase AMP deaminase Inosine monophosphate synthase DCMP deaminase GTP cyclohydrolase I Cytidine deaminase AICDA Activation-induced cytidine deaminase
3.5.5: Nitriles/ Aminohydrolases	Nitrilase
3.5.99: Other	Riboflavinase Thiaminase II

v t e Enzymes
Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Diffusion-limited enzyme Cofactor Enzyme catalysis
Regulation	Allosteric regulation Cooperativity Enzyme inhibitor Enzyme activator
Classification	EC number Enzyme superfamily Enzyme family List of enzymes
Kinetics	Enzyme kinetics Eadie–Hofstee diagram Hanes–Woolf plot Lineweaver–Burk plot Michaelis–Menten kinetics
Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list) EC7 Translocases (list)