Biochem/physiol Actions

Cytochrome P450 is a heterogeneous family of isozymes whose primary function is to oxidize small molecules, both as a function of intermediary metabolism (e.g., fatty acids) and to detoxify exogenous compounds (drugs or toxins). Some isoforms have narrow substrate specificity, while others are promiscuous.

Other Notes

Microsomes containing recombinant human CYP3A4 and recombinant rabbit NADPH-P450 reductase

Physical form

Solution in 100 mM potassium phosphate buffer, pH 7.4.

Unit Definition

One unit will convert 1 nanomole of testosterone to 6β-hydroxytestosterone per minute at pH 7.4 at 37 °C.