Efavirenz primary and secondary metabolism was investigated in vitro and in vivo. In human liver microsome (HLM) samples, 7- and 8-hydroxyefavirenz accounted for 22.5 and 77.5% of the overall efavirenz metabolism, respectively. Kinetic, inhibition, and correlation analyses in HLM samples and experiments in expressed cytochrome P450 show that CYP2A6 is the principal catalyst of efavirenz 7-hydro...

The C-8 position of deoxyguanosine (dGuo) was hydroxylated by ascorbic acid in the presence of oxygen (O2) in 0.1 M phosphate buffer (pH 6.8) at 37 degrees C. Addition of hydrogen peroxide (H2O2) remarkably enhanced this hydroxylation. The Udenfriend system [ascorbic acid, FeII, ethylenediaminetetraacetic acid (EDTA) and O2] was also effective for hydroxylation of dGuo in high yield. Guanine re...

The first dedicated step in plant xanthophyll biosynthesis is carotenoid hydroxylation. In Arabidopsis thaliana, this reaction is performed by both heme (LUT1 and LUT5) and non-heme (CHY1 and CHY2) hydroxylases. No mutant completely abolishing alpha- or beta-carotene hydroxylation has been described to date. We constructed double and triple mutant combinations in CHY1, CHY2, LUT1, LUT5 and LUT2...

background: several effects of volatile organic compounds (vocs) have been recognized such as toxic and carcinogenic human health effects. to evaluate cancer risk of benzenes air samples were taken, at an automobile manufacturing painters in tehran following inhalation exposure. methods: to perform this study, cross-sectional was done in 2016. sampling was carried out by active pump sampler usi...

in this research, the selective oxidation of benzene to maleic anhydride (man) in a fixed-bed reactor was studied. the gas phase catalytic oxidation of benzene was carried outin a laboratory scale fixed bed reactor on the catalysts, which were prepared having two different compositions on silica gel. the effects of temperature, flow rates of benzene and air, and catalyst type on the reaction se...

The isolation, purification, and cloning of the mitochondrial P450 enzyme catalyzing not only the 27-hydroxylation of 5 beta-cholestane-3 alpha, 7 alpha-diol and cholestane-3 alpha, 7 alpha, 12 alpha-triol, but also the 25-hydroxylation of vitamin D3 are reviewed. The sterol hydroxylase was shown to be present on the mitochondrial inner membrane-matrix, to be inactivated by carbon monoxide, and...

The asparaginyl hydroxylase FIH [factor inhibiting HIF (hypoxia-inducible factor)] was first identified as a protein that inhibits transcriptional activation by HIF, through hydroxylation of an asparagine residue in the CAD (C-terminal activation domain). More recently, several ARD [AR (ankyrin repeat) domain]-containing proteins were identified as FIH substrates using FIH interaction assays. A...

Background: Benzene has been classified as group 1 human carcinogens in the environment by the International Agency for Research on Cancer (IARC) mainly because of its ability to cause acute myeloid leukemia (AML). This study was conducted to detect any probable association between urban benzene pollution concentration and occurrence of AML in different regions of Tehran.  Methods: In thi...

An unspecific peroxygenase from Aspergillus brasiliensis highly expressed in Pichia pastoris catalyses aromatic hydroxylation of a number benzylic compounds.