A sensing method based on resonance localized surface plasmon spectroscopy was developed for low molecular weight substrate and inhibitor molecules binding to heme proteins. Cytochrome P450 proteins have Soret and Q absorption bands in the visible wavelength region. The coupling between the molecular resonance of P450 and the localized surface plasmon resonance (LSPR) of functionalized silver n...

The present study examined the utility of an immunoblot method for quantitation of cytochrome P450 isozymes in archived liver samples as a bioassay of exposure to halogenated hydrocarbons. Hepatic microsomes were prepared from 44 archived polar bear (Ursus maritimus) liver homogenates that had been stored at approximately -40 degrees C for 9-10 years and analyzed on blots probed with antibodies...

Specific metabolic roles of P450-dependent monooxygenase systems are determined by enzymatic properties and substrate specificity of P450s, the terminal enzymes of the electron transfer chain. On the other hand, molecular diversity has also been reported for NADPH-cytochrome P450 reductase, cytochrome b5, and cytochrome b5 reductase in plants. Several lines of evidence indicate that the electro...

A unique metabolite with a molecular mass of 119 Da (C(2)H(5)N(3)O(3)) accumulated during biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Rhodococcus sp. strain DN22 (D. Fournier, A. Halasz, J. C. Spain, P. Fiurasek, and J. Hawari, Appl. Environ. Microbiol. 68:166-172, 2002). The structure of the molecule and the reactions that led to its synthesis were not known. In the p...

Cytochrome P450 BM3 (P450 102) from Bacillus megaterium is a unique bacterial P450, formed from the fusion of a fatty acid hydroxylase to a eukaryotic-like NADPH-cytochrome P450 reductase flavoprotein in a single (1 19 kDa) polypeptide chain (1, 2). It is an attractive model system for enzymological and structural studies due to its homology with mammalian drug metabolising P450 systems, and wi...

The results of a limited number of studies on echinoderms provide evidence for the presence of a cytochrome P450 monooxygenase system in representatives of three classes of the phylum Echinodermata: the asteroids (sea stars), holothuroids (sea cucumbers) and echinoids (sea urchins). The monooxygenase system has been demonstrated to be involved in the metabolism of xenobiotic compounds, but is a...

cyp3a4 probably has the broadest catalytic activity of any cytochrome p450. it is a crucial task to test new drug candidates in a reliable system for their ability to induce expression of this enzyme. firstly, a total of 300 bp core distal enhancer of cyp3a4 xrem region (-7972/-7673) were amplified from human genomic dna. the pcr product was then ligated into a human secretory alkaline phosphat...

The studies presented here were designed to elucidate the enzymes involved in the biotransformation of naturally occurring 1, 8-dihydroxyanthraquinones and to investigate whether biotransformation of 1,8-dihydroxyanthraquinones may represent a bioactivation pathway. We first studied the metabolism of emodin (1, 3,8-trihydroxy-6-methylanthraquinone), a compound present in pharmaceutical preparat...

A cytochrome P450 was purified from microsomes of Rhodotorula minuta. The optical spectrum of the purified cytochrome was characteristic of a low-spin ferric heme protein. Isovalerate caused a type I spectral change in it. The amino-terminal sequence of the cytochrome was different from those of other known microsomal cytochrome P450s. These results indicate that the cytochrome, which is tentat...