Merck

Measurement of cytochrome P450 and NADPH-cytochrome P450 reductase.

Nature protocols (2009-08-08)
F Peter Guengerich, Martha V Martin, Christal D Sohl, Qian Cheng
ABSTRACT

Cytochrome P450 (P450) enzymes are important in the metabolism of steroids, vitamins, carcinogens, drugs and other compounds. Two of the commonly used assays in this field are the measurements of total P450 and NADPH-P450 reductase in biological preparations. A detailed protocol is presented for the measurement of P450 by its spectral properties, along with a protocol for measuring NADPH-P450 reductase by its NADPH-cytochrome c reduction activity. Each assay can be completed in 5-10 min. Detailed explanations for the rationale of particular sequences in the protocols are provided, along with potential confounding problems.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Sodium cholate hydrate, BioXtra, ≥99%
Sigma-Aldrich
Triton N-101, reduced