In this study we have replaced all 13 methionine residues in the cytochrome P450 BM-3 heme domain (463 amino acids) with the isosteric methionine analog norleucine. This experiment has provided a means of testing the functional limits of globally incorporating into an enzyme an unnatural amino acid in place of its natural analog, and also an efficient way to test whether inactivation during per...

The cytochrome P450 (P450) superfamily metabolizes many endogenous signaling molecules and drugs. P450 enzymes are regulated by posttranslational mechanisms in vivo, which hinders their functional characterization by conventional genomic or proteomic methods. Here we describe a chemical proteomic strategy to profile P450 activities directly in living systems. Derivatization of a mechanism-based...

The eukaryotic microsomal cytochrome P450 systems consist of a cytochrome P450 enzyme (P450) and a cytochrome P450 redox partner, which generally is a cytochrome P450 reductase (CPR) that supplies electrons from NADPH. However, alternative electron donors may exist such as cytochrome b5 reductase and cytochrome b5 (CBR and CYB5, respectively) via, which is NADH-dependent and are also anchored t...

The cytochrome P450 enzyme superfamily (CYP), E.C. 1.14.-.-, are haem-containing monooxygenases with a vast range of both endogenous and exogenous substrates. These include sterols, fatty acids, eicosanoids, fat-soluble vitamins, hormones, pesticides carcinogens as well drugs. Listed below the human enzymes, their relationship rodent CYP activities is obscure in that species orthologue may not ...

Fungal nitric oxide reductase (cytochrome P450 nor) is a heme-containing enzyme, in which the iron-porphyrin complex is an active site of the enzyme. This enzyme is involved in the fungal denitrification process, and catalyzes the reduction of NO to N2O. Its structural and functional characteristics were examined by enzymatic, kinetic, spectroscopic (optical absorption, ESR, resonance Raman, IR...

Detection of drug-drug interactions is essential during the early stages of drug discovery and development, and the understanding of drug-botanical interactions is important for the safe use of botanical dietary supplements. Among the different forms of drug interactions that are known, inhibition of cytochrome P450 (P450) enzymes is the most common cause of drug-drug or drug-botanical interact...

The monooxygenase P450 BM-3 is a NADPH-dependent fatty acid hydroxylase enzyme isolated from soil bacterium Bacillus megaterium. As a pivotal member of cytochrome P450 superfamily, it has been intensely studied for the comprehension of structure-dynamics-function relationships in this class of enzymes. In addition, due to its peculiar properties, it is also a promising enzyme for biochemical an...