Fungi are an exceptional source of diverse and novel cytochrome P450 monooxygenases (P450s), heme-thiolate proteins, with catalytic versatility. Agaricomycotina saprophytes have yielded most of the available information on basidiomycete P450s. This resulted in observing similar P450 family types in basidiomycetes with few differences in P450 families among Agaricomycotina saprophytes. The prese...

The common marmoset (Callithrix jacchus), a New World monkey, has potential to be an animal model for drug metabolism studies. In this study, we identified and characterized cytochrome P450 (P450) 1A1 and 1B1 in addition to the known P450 1A2 in marmosets. Marmoset P450 1A1 and 1B1 cDNA contained open reading frames encoding 512 and 543 amino acids, respectively, with high sequence identities (...

The volatile anesthetic halothane undergoes substantial biotransformation generating metabolites that mediate hepatotoxicity. Aerobically, halothane undergoes cytochrome P450-catalyzed oxidation to trifluoroacetic acid (TFA), bromide and a reactive intermediate that can acetylate liver proteins. These protein neo-antigens stimulate an immune reaction that mediates severe hepatic necrosis ("halo...

The homologous rat cytochrome P450s 2B1 and 2B2 differ by 13 amino acids. A chimeric construct of P450 2B1/2B2 was used in conjunction with several site-directed mutants to identify key residues involved in the inactivation of P450 2B1 by two acetylenic compounds, 17alpha-ethynylestradiol (17EE) and tert-butyl 1-methyl-2-propynyl ether (tBMP). 17EE is a mechanism-based inactivator of P450 2B1 b...

Cytochrome P450 (P450) 2B5 was recently found to be functionally distinct from three other rabbit P450 2B forms, based on androstenedione hydroxylase activities. In this investigation, we examined the frequency of the P450 2B5-null phenotype and the functional consequences of polymorphic P450 2B5 expression in hepatic microsomes from phenobarbital-treated rabbits. Four of the 10 animals examine...

Investigation of Performance and Comparison Cytochrome P450 Isoforms in Broiler Chickens Liver Fed Silver Nanoparticles Coated on Clinoptilolite

Cytochrome P450 monooxygenases (P450s) are heme-thiolate proteins whose role as drug targets against pathogens, as well as in valuable chemical production and bioremediation, has been explored. In this study we performed comprehensive comparative analysis of P450s in 13 newly explored oomycete pathogens. Three hundred and fifty-six P450s were found in oomycetes. These P450s were grouped into 15...

The potent antioxidants licorice root extract and glabridin, an isoflavan purified from licorice root extract, were tested for their ability to modulate the activities of several cytochrome P450 (P450) enzymes. P450 3A4, the major human drug metabolizing P450 enzyme, was inactivated by licorice root extract and by glabridin in a time-and concentration-dependent manner. The inactivation was NADP...

Cytochrome P450 (P450) enzyme expression patterns were determined for a panel of 60 human tumor cell lines, representing nine tumor tissue types, used by the National Cancer Institute (NCI) Anticancer Drug Screening Program. All 60 tumor cell lines displayed significant P450 activity, as well as P450 reductase activity, as determined using the general P450 substrate 7-benzyloxyresorufin. Cell l...

The polymorphic human cytochrome P450 (P450) 2B6 is primarily responsible for the metabolism of several clinically relevant drugs including bupropion, cyclophosphamide, propofol, and efavirenz. Although a number of single nucleotide polymorphisms have been found in the P450 2B6 gene, the influence of these variants on the metabolism of substrates and on the response to known inactivators of P45...