Cytochrome P450 complex

In conclusion, oximes are produced in nature mostly, but not exclusively, as intermediates of secondary metabolites by enzymic oxidation of an amine function. The oxygenation is mediated by cytochrome P450 complex enzymes and FMOs. However, their formation via condensation of a carbonyl moiety with HA cannot be excluded. 

The active oxygen -cytochrome P450 complex is a powerful oxidizing agent towards almost any organic compound, including alkanes, and the central iron-porphyrin complex has been depicted as... 

Ligand Conformational Equilibrium in a Cytochrome P450 Complex... 

In order to study the metabolism of arachidonic acid by the cytochrome P450 complex, Nithipatikom et al. [38] developed a negative-ion LC-ESI-MS method for the quantitative determination of 5,6-, 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids (EET), their corresponding diHET, and 20-HETE. The analytes and their deuterium-labelled internal standards were measured as [M-H] in selected-ion monitoring (SIM) mode. The detection limit was 1 pg (2-mm-ID column). 

Metabolic activation of carcinogens involves many enzymatic systems, known as phase I enzymes. The most important is the cytochrome P450 complex, consisting of several different isoenzymes, which are particularly active in the liver. Other enzymes include peroxidases, quinone reductases, epoxide hydrolases, sulfotrans-ferases, and others. Their variety reflects the diversity of chemical structures of compounds to which an organism is exposed. These may be harmful substances or needed ones, or even those indispensable for its proper functioning. One could argue that the activation of carcinogens is an undesirable side effect of metabolic pathways,... 

Mansuy, D. and M. Fontecave (1983). Reduction of benzyl halides by liver microsomes Formation of 478 nm-absorbing sigma-alkyl-ferric cytochrome P450 complexes. Biochem. Pharmacol. 32, 1871-1879. 

Usia, T., T. Watabe, S. Kadota, and Y. Tezuka. 2005a. Metabolite-cytochrome P450 complex formation by methylenedioxyphe-nyl lignans of Piper cubeba Mechanism-based inhibition. Life Sci. 76(20) 2381-2391. 

Characterization of the (TPP)Fe(l,3-benzodioxol-2-carbene) complex (Eq. 8) was also reported, giving indirect evidence for the presence of this carbene as a ligand in the benzodioxole-derived cytochrome P450 complex (Eq. 9) [7,16]. 

S. Ahuja, N. Jahr, S.-C. Im, S. Vivekanandan, N. Popovych, S.V. Le Clair, R. Huang, R. Soong, J. Xu, K. Yamamoto, R.P. Nanga, A. Bridges, L. WaskeU, A. Ramamoorthy, A model of the membrane-bound cytochrome-bound b5-cytochrome P450 complex from NMR and mutagenesis data, J. Biol. Chem. 288 (2013) 22080-22095. 

Carletti M, Gusson F, Zaghini A, Dacasto M, Mar-vasi L, Nebbia C (2003) In vitro formation of metabolic-intermediate cytochrome P450 complexes in rabbit liver microsomes by tiamulin and various macrolides. Vet Res 34 405 11... 

ROS, hydroxyl radicals ( OH) (the so-called Fenton reaction). Cytochrome P450 complexes in the endoplasmic reticulum generate superoxides to metabolize toxic hydrophobic compounds and phagocytes produce superoxides, hydrogen peroxide and hydroxyl radicals to kill infectious microorganisms and cancer cells." ... 

To estimate the health risks represented by brominated flame retardants, it is important to consider, in addition to assessment of the potential routes of exposure, the biotransformation of these compounds in the body. The most abundant congener BDE 47 (2,2, 4,4 -tetrabromodiphenylether) occurring in biotic materials is absorbed up to 95% in the gastrointestinal tract of mice, distributed to the tissues and slowly metabolised. Only a small amount is excreted via excrements. Similarly, as in the case of aromatic xenobiotics, by the action of cytochrome, P450 complex epoxides are produced as the primary products, which, on hydrolysis, yield the corresponding hydroxy derivatives (Figure 12.52). 

Cytochrome b5-cytochrome P450 complex Detergent micelles and Upid bicelles 99... 

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