| Prostaglandin-endoperoxide synthase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.14.99.1 | ||||||||
| CAS no. | 9055-65-6 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
| Cyclooxygenase 1 | |||||||
|---|---|---|---|---|---|---|---|
 Crystallographic structure of prostaglandin H2 synthase-1 complex with flurbiprofen[1] | |||||||
| Identifiers | |||||||
| Symbol | PTGS1 | ||||||
| Alt. symbols | COX-1 | ||||||
| NCBI gene | 5742 | ||||||
| HGNC | 9604 | ||||||
| OMIM | 176805 | ||||||
| PDB | 1CQE | ||||||
| RefSeq | NM_080591 | ||||||
| UniProt | P23219 | ||||||
| Other data | |||||||
| EC number | 1.14.99.1 | ||||||
| Locus | Chr. 9 q32-q33.3 | ||||||
| |||||||
| Cyclooxygenase 2 | |||||||
|---|---|---|---|---|---|---|---|
 Cyclooxygenase-2 (prostaglandin synthase-2) in complex with a COX-2 selective inhibitor[2] | |||||||
| Identifiers | |||||||
| Symbol | PTGS2 | ||||||
| Alt. symbols | COX-2 | ||||||
| NCBI gene | 5743 | ||||||
| HGNC | 9605 | ||||||
| OMIM | 600262 | ||||||
| PDB | 6COX | ||||||
| RefSeq | NM_000963 | ||||||
| UniProt | P35354 | ||||||
| Other data | |||||||
| EC number | 1.14.99.1 | ||||||
| Locus | Chr. 1 q25.2-25.3 | ||||||
| |||||||
Cyclooxygenase (COX), officially known as prostaglandin-endoperoxide synthase (PTGS), is an enzyme (specifically, a family of isozymes, EC 1.14.99.1) that is responsible for biosynthesis of prostanoids, including thromboxane and prostaglandins such as prostacyclin, from arachidonic acid. A member of the animal-type heme peroxidase family, it is also known as prostaglandin G/H synthase. The specific reaction catalyzed is the conversion from arachidonic acid to prostaglandin H2 via a short-living prostaglandin G2 intermediate.[3][4]
Pharmaceutical inhibition of COX can provide relief from the symptoms of inflammation and pain.[3] Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, exert their effects through inhibition of COX. Those that are specific to the COX-2 isozyme are called COX-2 inhibitors. The active metabolite (AM404) of paracetamol is a COX inhibitor, a fact to which some or all of its therapeutic effect has been attributed.[5]
In medicine, the root symbol "COX" is encountered more often than "PTGS". In genetics, "PTGS" is officially used for this family of genes and proteins because the root symbol "COX" was already used for the cytochrome c oxidase family. Thus, the two isozymes found in humans, PTGS1 and PTGS2, are frequently called COX-1 and COX-2 in medical literature. The names "prostaglandin synthase (PHS)", "prostaglandin synthetase (PHS)", and "prostaglandin-endoperoxide synthetase (PES)" are older terms still sometimes used to refer to COX.
- ^ PDB: 1CQE; Picot D, Loll PJ, Garavito RM (January 1994). "The X-ray crystal structure of the membrane protein prostaglandin H2 synthase-1". Nature. 367 (6460): 243–9. Bibcode:1994Natur.367..243P. doi:10.1038/367243a0. PMID 8121489. S2CID 4340064.
- ^ PDB: 6COX; Kurumbail RG, Stevens AM, Gierse JK, McDonald JJ, Stegeman RA, Pak JY, Gildehaus D, Miyashiro JM, Penning TD, Seibert K, Isakson PC, Stallings WC (1996). "Structural basis for selective inhibition of cyclooxygenase-2 by anti-inflammatory agents". Nature. 384 (6610): 644–8. Bibcode:1996Natur.384..644K. doi:10.1038/384644a0. PMID 8967954. S2CID 4326310.
- ^ a b Litalien C, Beaulieu P (2011). "Chapter 117 – Molecular Mechanisms of Drug Actions: From Receptors to Effectors". In Fuhrman BP, Zimmerman JJ (eds.). Pediatric Critical Care (4th ed.). Philadelphia, PA: Elsevier Saunders. pp. 1553–1568. doi:10.1016/B978-0-323-07307-3.10117-X. ISBN 978-0-323-07307-3.
Arachidonic acid is a component of membrane phospholipids released either in a one-step process, after phospholipase A2 (PLA2) action, or a two-step process, after phospholipase C and DAG lipase actions. Arachidonic acid is then metabolized by cyclooxygenase (COX) and 5-lipoxygenase, resulting in the synthesis of prostaglandins and leukotrienes, respectively. These intracellular messengers play an important role in the regulation of signal transduction implicated in pain and inflammatory responses.
- ^ Liu J, Seibold SA, Rieke CJ, Song I, Cukier RI, Smith WL (June 2007). "Prostaglandin endoperoxide H synthases: peroxidase hydroperoxide specificity and cyclooxygenase activation". The Journal of Biological Chemistry. 282 (25): 18233–44. doi:10.1074/jbc.M701235200. PMID 17462992.
- ^ Högestätt ED, Jönsson BA, Ermund A, Andersson DA, Björk H, Alexander JP, Cravatt BF, Basbaum AI, Zygmunt PM (September 2005). "Conversion of acetaminophen to the bioactive N-acylphenolamine AM404 via fatty acid amide hydrolase-dependent arachidonic acid conjugation in the nervous system" (PDF). The Journal of Biological Chemistry. 280 (36): 31405–12. doi:10.1074/jbc.M501489200. PMID 15987694. S2CID 10837155.