Cytochrome P450 2C9 (CYP2C9)

Cytochromes 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 (PubMed:25994031). This enzyme contributes to the wide pharmacokinetics variability of the metabolism of drugs such as S-warfarin, diclofenac, phenytoin, tolbutamide and losartan (PubMed:25994031).