LMPD Database

LMP000430

UniProt Annotations

Entry Information
Gene Namecytochrome P450, family 1, subfamily A, polypeptide 2
Protein EntryCP1A2_HUMAN
UniProt IDP05177
SpeciesHuman
Comments
Comment typeDescription
Alternative ProductsEvent=Alternative splicing; Named isoforms=2; Name=1; IsoId=P05177-1; Sequence=Displayed; Name=2; IsoId=P05177-2; Sequence=VSP_017123;
Biophysicochemical PropertiesKinetic parameters: KM=4 uM for 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole ; KM=21 uM for 2-amino-3-methylimidazo[4,5-f]quinoline ; KM=26 uM for 2-amino-2,4-dimethylimidazo[4,5-f]quinoline ; KM=27 uM for 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline ; KM=71 uM for 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine ; KM=25 uM for phenacetin ;
Catalytic ActivityRH + reduced flavoprotein + O(2) = ROH + oxidized flavoprotein + H(2)O.
CofactorName=heme; Xref=ChEBI
FunctionCytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Most active in catalyzing 2-hydroxylation. Caffeine is metabolized primarily by cytochrome CYP1A2 in the liver through an initial N3-demethylation. Also acts in the metabolism of aflatoxin B1 and acetaminophen. Participates in the bioactivation of carcinogenic aromatic and heterocyclic amines. Catalizes the N-hydroxylation of heterocyclic amines and the O- deethylation of phenacetin.
InductionBy nicotine, omeprazole, phenobarbital, primidone and rifampicin.
PolymorphismThe CYP1A2*1F allele which is quite common (40 to 50%) is due to a substitution of a base in the non-coding region of the CYP1A2 gene and has the effect of decreasing the enzyme inducibility. Individuals who are homozygous for the CYP1A2*1F allele are 'slow' caffeine metabolizers. Thus for these individual increased intake of caffeine seems to be associated with a concomitant increase in the risk of non-fatal myocardial infraction (MI).
SimilarityBelongs to the cytochrome P450 family.
Subcellular LocationEndoplasmic reticulum membrane; Peripheral membrane protein. Microsome membrane; Peripheral membrane protein.
Tissue SpecificityLiver.
Web ResourceName=Cytochrome P450 Allele Nomenclature Committee; Note=CYP1A2 alleles; URL="http://www.cypalleles.ki.se/cyp1a2.htm";
Web ResourceName=NIEHS-SNPs; URL="http://egp.gs.washington.edu/data/cyp1a2/";