Cytochrome P450 reductase (POR)

Cytochrome P450 reductase (POR) is a membrane-bound diflavin oxidoreductase that catalyzes the transfer of electrons from NADPH to all microsomal cytochrome P450 enzymes and other endoplasmic reticulum-associated heme proteins, such as heme oxygenase. It contains both FAD and FMN cofactors within distinct domains and is essential for the activity of cytochrome P450s in the metabolism of drugs, steroids, lipids, and xenobiotics. In humans, the POR gene is located on chromosome 7q11.23. Structural flexibility, enabled by hinge regions between domains, allows POR to interact with multiple cytochrome P450 isoforms and deliver electrons sequentially, facilitating the catalytic activities of these enzymes in detoxification and biosynthetic processes. Mutations in POR can cause disorders including altered steroidogenesis, skeletal malformations, and atypical drug responses due to changes in cytochrome P450–mediated metabolism

Other names

NADPH–cytochrome P450 reductaseNADPH:ferrihemoprotein oxidoreductaseNADPH:hemoprotein oxidoreductaseNADPH:P450 oxidoreductaseP450 reductasePORCPRCYPOR

Facilitates electron transfer from NADPH to microsomal cytochrome P450 enzymes and other heme proteins, enabling enzymatic activity such as hydroxylation, demethylation, and epoxidation in xenobiotic and endobiotic metabolism