• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.141-146
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• 1998

Feeding experiment of [$^3$H] 5-epi-aristolochene (5-EAS) demonstrated in suspension cultures of tobacco (Nicotiana tabacum L.) that 5-EAS hydroxylase activity was absent from control cells, but induced to a maximum level within 18 h after the addition of cellulase, and was very similar to induction pattern of sesquiterpene cyclase. This result suggest that the conversion of 5-EAS to capsidiol is catalyzed by at least one elicitor-inducible hydroxylase. Cytochrome P450 inhibitors, ancymidol and ketoconazole, suppressed the elicitor-induced capsidiol accumulation by inhibiting hydroxylase activity, suggesting that the hydroxylase may be a Cyt P450 type enzyme.

• Journal of Life Science
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• v.13 no.6
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• pp.879-888
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• 2003

In order to measure the enzyme activity of 5-epi-aristolochene hydroxylase, one of cytochrome P450 (P450) enzymes in eicitor-treated pepper cell, we used in vivo assay method and demonstrated a dramatic suppression of the activity by P450-inhibitors, ancymidol and ketocornazole. Using RT-PCR method with degenerate primer of the well conserved domains found within most P450-enzymes, and using cDNA library screening method, one distinct cDNA, being designated P450Hy01, was successfully isolated from elicitor-treated pepper cells. P450Hy01 mRNA was all induced in elicitor-treated cells whereas never induced in control cells. Moreover, levels of P450Hy01 expression were highly correlated with the levels of extracellular capsidiol production by different elicitors in cell cultures. P450Hy01 transcript was also induced by several other elicitors such as, cellulase, arachidonic acid, jasmonic acid, yeast extract as well as UV stress. P450Hy01 sequence contained high probability amino acid matches to known Plant P450 genes and ORF with a conserved FxxGxRxCxG heme-binding domain. P450Hy01 cDNA showed 98% of homology in sequence of nucleotide as well as amino acid to 5-epi-aristolochene-1, 3-hydroxylase (5EAl, 3H) which has been isolated in tobacco cells, suggesting that P450Hy01 is prominent candidate gene for P450-enzyme encoding 5EAl, 3H in pepper cell.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.78-86
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• 1992

The induction of hepatic cytochromes P450 and metabolic effects have been examined in male and female Sprague-Dawley rats following treatment with either phenobarbital or 3-methylcholanthrene. Hepatic cytochrome P450 levels were higher in males than in females by ~40%. Treatment of male and female rats with phenobarbital or 3-methylcholanthrene resulted in an ~1.6 and 2-fold increase, respectively, in heptic microsomal cytochrome P450 levels in both sexes, relative to untreated animals. Immunoblot analyses were performed to compare sex-related changes in P450 levels. Hepatic P45IIB1 levels in males were greater than those in females following phenobarbital treatment. 3-Methylcholanthrene-induced male hepatic microsomes exhibited greater levels of P450 females failed to exhibit a band. Mab PCN 2-13-1 against P-45-IIIA recognized an intense in uninduced microsomes from female rats. The levels of P450IIIA in males were increased 2 to 3-fold following treatment with phenobarbital, while the increase of IIIA levels in females by phenobarbital was minimal, as monitored by immunoblot analysis. Solid phase radiommunoassay using monoclonal antibodies supported the results of immunoblot analysis. Phenobarbital treatment caused a 6.5-fold increase in the monoclonal iantibody binding to IIBI in males, whereas treatment of females with phenobarbital resulted of IA levels by 3-methylcholanthrene was also greater in females than in males (10-vs. 8-fold) although the levels of induced IA were comparable inboth sexes, as assessed by radiommunoassay. Radioimmunoassay also showed that hepatic IIEI level was 1.5-fold higher in males than in females and that either phenobarbital or 3-methylcholanthrene treatment caused 80% to 40% decrease in IIEL levels, relative to control, in both sexes. Sex-related metabolic activities were examined in hepatic microsomes. Hexobarbital hydroxylase activity was 2-to 3-fold higher in uninduced microsomes from males than that from females. This hydroxylase activity was increased 2-and 3-fold in males and females, respectively, following phenobarbital treatment, as compared to controls. Addition females produced 64% and 84% inhibition of hexobarbital oxidation, respectively. Aryl hydrocarbon hydroxylase activity was increased -12 and 26-fold in males and females respectively. Following phenobarbital treatment, as compared to controls. Addition of anti-P450IIB1 antibody to phenobarbital-induced hepatic microsomes from males and females produced 64% and 84% inhibition of hexobarbital oxidation, respectively. Aryl hydrocarbon hydroxylase activity was increased -12 and 26 fold in males and females, respectively, following 3-methylcholanthrene treatment relative to controls. The anti-P-450IA antibody inhibitable rate of aryl hydrocarbon hydroxylase activity was comparable in both sexes following 3-methylcholanthrene treatment relative to controls. The anti-P450LA antibody inhibitable rate of aryl hydrocarbon hydroxylase activity was comparable in both sexes following 3-methylcholanthrene treatment (-70%). These results demonstrate that levels of hepatic P450IIB1 or P450IA are greater in male than in female for untreated, phenobarbital-or-3-methylcholanthrene treated rats. In addition, the relative for untreated phenobarbital-or 3-methylcholanthrene treated rats. In addition, the relative increase of phenobarbital-or 3-methylcholanthrene treated rats. In addition, the relative increase of phenobarbital-or 3-methylcholanthrene treated rats. In addition, the relative increase of P450IIB1 or IA phenobarbital or 3-methylcholanthrene is more significant in females.

• Animal cells and systems
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• v.9 no.1
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• pp.19-25
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• 2005

This study was conducted to determine the effect of dietary salt on the synthesis of glucocorticoids in the adrenal cortex of mice. Mice had ad libitum access to 3% sodium chloride as the only drinking fluid (high salt diet) for either 4 days or 4 weeks. Adrenocortical expression of cytochrome P450 11beta-hydroxylase, a major regulatory enzyme in the biosynthesis of glucocorticoids, was examined by immunohistochemistry and western blot analysis. Ultrastructure of adrenocortical cell and plasma level of corticosterone were analyzed as well. Size and density of lipid droplets in the cortical cell were increased by high salt diet. Four days of high salt diet decreased P450 11beta-hydroxylase in the adrenal cortex, but 4 weeks increased it. Plasma level of corticosterone changed in parallel with the Cortical level of P450 11 beta-hydroxylase. These results suggest that high salt diet may modulate the biosynthesis of glucocorticoids, at least partly, via regulating the expression of P450 11beta-hydroxylase in adrenocortical cells.

• Archives of Pharmacal Research
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• v.9 no.2
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• pp.81-86
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• 1986

The effect of imperatorin on hepatic microsomal mixed function oxidases (MF0) was investigated. On acute treatment, imperatorin (30 mg/kg, i.p) caused a significant reduction in activities of hepatic aminopyrine N-demethylase, hexobarbital hydroxylase and aniline hydroxylase as well as cytochrome p0450 content in rats and mice. Kinetic studies on rat liver enzymes revealed that imperatorin appeared to be a competitive inhibitor of aminopyrine N-demethylase (Ki,0.007 mM), whereas a non-competitive inhibitor of hexobarbital hydroxylase (Ki, 0.0148 mM). Imperatorin also inhibited non-competitively aniline metabolism (Ki 0.2 mM). Imperatorin binds to phenobarbital-induced cytochrome p-450 to give a typical type 1 binding sepctrum (max. 388nm, min 422 nm). Multiple administrations of imperatorin (30 mg/kg. i. p. daily for 7 days) to mice shortended markedly the duration of hexobarbital narcosis and increased activities of hepatic aminopyrine N-demethylase and hexobarbital hydroxylase and the level of cytochrome p-450 where as aniline hydroxylase activity was unaffected.

• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.295-299
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• 1998

Oligonucleotide primers were designed and successfully applied to amplify DNA fragments of P450 hydroxylase genes from actinomycetes which produce a large variety of medically important metabolites. Primers were designed based on several regions of strong similarities in amino acid sequence of P450 hydroxylases from a variety of actinomycetes, primarily in the regions of an oxygen binding site and a heme ligand pocket. These primers were used to amplify DNA fragments from seven different actinomycetes species producing a variety of different compounds. The deduced amino acid sequences of the isolated fragments revealed significant similarities to known P450 hydroxylase including the product of the suaC or subC genes from Streptomyces griseolus that is capable of metabolizing a number of sulfonylurea herbicides, and to the product of the $P450_{sca2}$ from S. carbophilus that produces a specific HMG-CoA reductase inhibitor. This method should help researchers in cloning the P450 hydroxylase genes involved in the biosynthesis of useful compounds.

• Development and Reproduction
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• v.10 no.2
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• pp.127-133
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• 2006

[ $17\;{\alpha}-hydroxylase/17,20-lyase(P450_{C17})$ ] is the key enzyme mediating the conversion of progesterone to $17\;{\alpha}-hydroxyprogesterone$, ultimately to androstenedione during steroidogenesis. R. dybowskii's ovarian $P450_{C17}$ cDNA was cloned to understand the regulatory mechanism of ovarian steroidogenic pathway at the molecular level in amphibian. A 2.5kb cDNA clone encoding a single open-reading frame with a 519 deduced amino acid was isolated with the screening of ovarian cDNA library. This sequence contained the three highly conserved domains as seen in $P450_{C17}$ of other species. The comparison of amino acid sequence of Rana $P450_{C17}$ with other animal's $P450_{C17}$ showed relatively high identity with 76% in Xenopus, 63% in chicken, 60% in rainbow trout, and 45% in human. Phylogenic analysis also indicated that Rana $P450_{C17}$ gene was evolutionary well conserved among vertebrate. Northern analysis indicated that the two different sizes of $P450_{C17}$ transcripts with approximately 2.5 and 3.6kb were detected in ovary tissue, but not in other tissues. The expression vector of Rana $P450_{C17}$ clearly showed the $17\;{\alpha}-hydroxylase$ activity converting the exogenous progesterone into $17\;{\alpha}-hydroxyprogesterone$ in the nonsteroidogenic COS-1 cells. Therefore, Rana $P450_{C17}$ cDNA is very useful to investigate the molecular mechanism of the ovarian steroidogenesis in amphibian.

• YAKHAK HOEJI
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• v.32 no.5
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• pp.295-303
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• 1988

For microbial production of acetaminophen, a popular analgesic-antipyretic from aniline, we screened various fungi and bacteria. And we succeeded to some extents in acetaminophen production by successful protoplast fusion between S. lividans and S. globisporus and also between S. rimosus and S. aureofaciens. However, more fertile results might be brought via performing the cloning of acetanilide p-hydroxylation genes of Streptomyces in yeast. This study was initiated to determine whether the acetanilide p-hydroxylase of Streptomyces is cytochrome P-450 species or non-heme iron protein species. The p-hydroxylationactivity on acetanilide in S. aureofaciens ATCC 10762 was found to be unstable on exposing to the air. However, 100,000xg supernatant of the cell free extracts which were prepared in $N_2$ atmosphere showed the p-hydroxylation activity. Characteristic absorption peak of cytochrome P-450 after reduction with dithionite and addition of CO was not observed in the region of 450nm. Moreover, metyrapone and 2, 6-dichloroindophenol did not affect this enzyme activity, but sodium azide, sodium cyanide, cupric sulfate, cadmium chloride, ${\alpha}$, ${\alpha}'-dipyridyl$, and o-phenanthroline reduced p-hydroxylase activity considerably. S. fradiae NRRL 2702 was shown to have strong p-hydroxylation activity in intact cells. This activity disappeared in its cell free extracts. In its 100,000xg supernatant, however, characteristic absorption peak of cytochrome P-450 after reduction with dithionite and addition of CO was observed at 446nm. Thus, the results herein presented suggest that acetanilide p-hydroxylase of Streptomyces aureofaciens is not related to cytochrome P-450 and may include non-heme iron protein for its activity. However, it is not clear whether acetanilide p-hydroxylase in S. fradiae belongs to the same category of S. aureofaciens.

• Korean Journal of Microbiology
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• v.40 no.3
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• pp.221-225
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• 2004

Novel cytochrome P450 hydroxylase (CYP) genes were isolated and characterized from P. autotrophica cosmid DNA library using an actinomycete CYP-specific PCR product as a screening probe. The cosmids containing four unique CYP genes (pESK601, 602, 603, 604, 605) were identified, and the four CYP genes were completely sequenced to be homologous to other known Actinomycetes CYP genes involved in various secondary metabolic pathways. Among all novel actinomycete CYP genes found in P. autotrophica, the CYP genes present in pESK601 were revealed to be highly homologous to the CYP genes involved in polyene-type amphotericin and nystatin antibiotic biosynthesis. The nucleotide sequences of the CYP flanking region in pESK601 also revealed the polyene-type biosynthetic genes, implying the presence of a cryptic polyene-type antifungal biosynthetic gene cluster in P. autotrophica.

• Journal of Microbiology
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• v.40 no.3
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• pp.211-218
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• 2002

A 4.8-kb DNA fragment encoding the P-450 type hydroxylase and ferredoxin genes was cloned from Pseudonocardia autotrophica IFO 12743 that can convert vitamin D$\_$3/ into its hydroxylated active forms. In order to isolate the P-450 gene cluster in this organism, we designed PCR primers on the basis of the regions of an oxygen binding site and a heme ligand pocket that are general characteristics of the P-450 hydroxylase. Sequencing analysis of the BamHI fragment revealed the presence of four complete and one incomplete ORFs, named PauA, PauB, PauC, and PauD, respectively. As a result of computer-based analyses, PauA and PauB have homology with enoyl-CoA hydratase from several organisms and the positive regulators belonging to the tetR family, respectively. PauC and PauD show similarity with SuaB/C proteins and ferredoxins, respectively, which are composed of P-450 monooxygenase systems for metabolizing two sulfonylurea herbicides in Streptomyces griseolus PauC shows the highest similarity with another CytP-450$\_$Sca2/ protein that is responsible for production of a specific HMG-CoA reductase inhibitor, pravastatin, in S. carbophilus. Cultures of Steptomyces lividans transformant, containing the P-450 gene cluster on the pWHM3 plasmid, was unable to convert vitamin D$\_$3/ to its hydroxylated forms.