CYP2B6

Cytochrome P450 2B6 is an enzyme that in humans is encoded by the CYP2B6 gene.^[5] CYP2B6 is a member of the cytochrome P450 group of enzymes. Along with CYP2A6, it is involved with metabolizing nicotine, along with many other substances.^[5]

CYP2B6
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 3IBD, 3QOA, 3QU8, 3UA5, 4I91, 4RQL, 4RRT, 4ZV8
Identifiers
Aliases	CYP2B6, CPB6, CYP2B, CYP2B7, CYP2B7P, CYPIIB6, EFVM, IIB1, P450, cytochrome P450 family 2 subfamily B member 6, Cytochrome P450 2B6
External IDs	OMIM: 123930; MGI: 88598; HomoloGene: 73894; GeneCards: CYP2B6; OMA:CYP2B6 - orthologs
Gene location (Human) Chr. Chromosome 19 (human)[1] Band 19q13.2 Start 40,991,282 bp[1] End 41,018,398 bp[1]
Gene location (Mouse) Chr. Chromosome 7 (mouse)[2] Band 7 A3|7 14.11 cM Start 25,597,045 bp[2] End 25,626,049 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in right lobe of liver buccal mucosa cell mucosa of paranasal sinus nasal epithelium kidney tubule tendon of biceps brachii mucosa of ileum mucosa of transverse colon olfactory zone of nasal mucosa metanephric glomerulus Top expressed in right lung lobe duodenum lacrimal gland parotid gland submandibular gland intestinal villus skin of abdomen Ileal epithelium skin of external ear jejunum More reference expression data BioGPS n/a
Gene ontology Molecular function iron ion binding arachidonic acid epoxygenase activity oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen metal ion binding heme binding oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen oxidoreductase activity steroid hydroxylase activity monooxygenase activity Cellular component organelle membrane endoplasmic reticulum membrane membrane intracellular membrane-bounded organelle endoplasmic reticulum cytoplasm Biological process steroid metabolic process epoxygenase P450 pathway cellular ketone metabolic process xenobiotic metabolic process organic acid metabolic process Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 1555 13088 Ensembl ENSG00000197408 ENSMUSG00000030483 UniProt P20813 P12791 RefSeq (mRNA) NM_000767 NM_009999 RefSeq (protein) NP_000758 n/a Location (UCSC) Chr 19: 40.99 – 41.02 Mb Chr 7: 25.6 – 25.63 Mb PubMed search [3] [4]
Wikidata
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Function

This gene, CYP2B6, encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum and its expression is induced by phenobarbital. The enzyme is known to metabolize some xenobiotics, such as the anti-cancer drugs cyclophosphamide and ifosphamide.^[5]

Gene

Transcript variants for this gene have been described; however, it has not been resolved whether these transcripts are in fact produced by this gene or by a closely related pseudogene, CYP2B7. Both the gene and the pseudogene are located in the middle of a CYP2A pseudogene found in a large cluster of cytochrome P450 genes from the CYP2A, CYP2B and CYP2F subfamilies on chromosome 19q.^[5]

CYP2B6 ligands

Following is a table of selected substrates, inducers and inhibitors of CYP2B6.

Inhibitors of CYP2B6 can be classified by their potency, such as:

• Strong inhibitor being one that causes at least a 5-fold increase in the plasma AUC values, or more than 80% decrease in clearance.^[6]
• Moderate inhibitor being one that causes at least a 2-fold increase in the plasma AUC values, or 50-80% decrease in clearance.^[6]
• Weak inhibitor being one that causes at least a 1.25-fold but less than 2-fold increase in the plasma AUC values, or 20-50% decrease in clearance.^[6]

Substrates	Inhibitors	Inducers
alfentanil[7] (opioid analgesic) bupropion[8][7] (antidepressant) clopidogrel[9] cyclophosphamide[7][8] (alkylating antineoplastic agent) efavirenz[7][8] (NNRTI) ifosfamide[7][8] (alkylating antineoplastic agent) ketamine[10] (dissociative anaesthetic) methadone[8] (opiate replacement therapy) methoxetamine[11] (dissociative agent, NMDA receptor antagonist) nevirapine[7] (NNRTI) propofol[7] (anesthetic) selegiline[12] sertraline[13] (antidepressant) sorafenib[8] (protein kinase inhibitor) tamoxifen[7] (SERM) valproic acid[7] (anticonvulsant) verapamil (minor/moderate sensitive substrates)[14][15]	Strong: orphenadrine[7][16] (anticholinergic) Artemisia annua[17] Moderate: selegiline[18] Unspecified potency chlorpyrifos (insecticide) clopidogrel (antiplatelet)[12] clotrimazole (antifungal)[12] curcumin (supplement)[19][20] (constituent of turmeric) ethinylestradiol (estrogen, contraceptive) fluoxetine (antidepressant)[21] fluvoxamine (antidepressant)[21] itraconazole (antifungal)[12] ketoconazole (antifungal)[21] memantine[22] (NMDA antagonist) paroxetine (antidepressant)[21] raloxifene (SERM)[12] sertraline (antidepressant)[12][21] thiotepa[8] (anticancer) ticlopidine[8] (antiplatelet)	carbamazepine[7] (anticonvulsant, mood stabilizer) phenobarbital[8] (anticonvulsant) phenytoin[8] (antiepileptic) rifampicin[7][8] (bactericidal) efavirenz[7] (virostatic)