• 제목/요약/키워드: P450 hydroxylase

검색결과 139건 처리시간 0.03초

알코올 전처치한 흰쥐에 Cyclohexane 투여가 Cytochrome P-450 dependent aniline hydroxylase 활성에 미치는 영향 (Effect of Cyclohexane Treatment on the Liver Cytochrome P-450 Dependent Aniline Hydroxylase Activity in Alcohol-pretreated Rats)

  • 김병렬;윤종국
    • 한국환경보건학회지
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    • 제29권2호
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    • pp.23-28
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    • 2003
  • To evaluate the effect of cyclohexane(CH) treatment on the liver cytochrome P-450 dependent aniline hydroxylase(CYPdAH) activity in alcohol-pretreated animals, CH(1.56 g/kg body weight) was intraperitoneally administered to Sprague-Dawley male rats, which had been drunk 15% alcohol in distilled water for 1,3 and 6 weeks. CH was injected to rats 4 times every other day and the animals were sacrificed at 24 hours after injection of CH. In the alcohol-pretreated rats, liver injuries were not demonstrated on the basis of the liver weight per body weight, the levels of serum alanine aminotransferase and hepatic microsomal glucose-6-phosphatase activities. By the CH treatment, alcohol-pretreated animals showed the significantly increased activity of hepatic microsomal CYPdAH. Concomitantly $V_{max}$ value in CYPdAH was more increased, whereas $K_{M}$ value more decreased in alcohol-pretreated animals by the treatment of CH. In conclusion, the increasing cause of microsomal CYPdAH in CH-treated rats pretreated with alcohol may be due to induction of enzyme protein in rat liver.r.r.

Enzymatic Study on Acetanilide p-Hydroxylase in Streptomyces fradiae

  • Jin, Hyung-Jong;Park, Ae-Kyung;Lee, Sang-Sup
    • Archives of Pharmacal Research
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    • 제15권3호
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    • pp.215-219
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    • 1992
  • S. fradiae exhibited the highest acetanilide p-hydroxylation activity among the Streptomyces spp. screened. Studies with inhibitors (metyrapone, 2. 6-dichloroindophenol, $\alpha,\alpha'$-dipyridyl, o-phenanthroline) and an absorption peak after CO treatment suggested that S. fradiae hydroxylase activity was due to cytochrome p-450. This hydroxylase activity was increased to ten times in the cell extract containing 0.5 mM sodium azide. Furthermore, the sedimentary activity in $105,000\times{g}$ centrifugal forces and solubilization of the activity with Triton-X 100 implied that this enzyme was membrane bound monooxygenase. pH Optimum of the enzyme was 6.5 in membrane bound state.

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담배 현탁배양 세포의 Elicitor 유도성 5-epi-Aristolochene Hydroxylase 유전자의 클로닝 (Cloning of Elicitor-Inducible 5-epi-Aristolochene Hydroxylase in Tobacco Cell Suspension Culture)

  • Soon Tae Kwon;In-Jung Lee;Joseph Chappell
    • 생명과학회지
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    • 제8권5호
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    • pp.604-613
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    • 1998
  • 담배의 phytoalexin으로 알려진 capsidiol 생합성의 마지막 단계에 관여하는 5-epi-aristolochene hydroxy-lase 유전자의 일부를 RT-PCR 방법으로 클로닝하였다. 클로닝한 CYP-B3는 콩, 완두 등의 cytochrome P450계의 유전자와 높은 동일성을 보였으며 heme 결합부위로 알려진 FxxGxRxCxG을 포함하고 있는 것으로 나타났다. 또한 CYP-B3는 저온, 고온 또는 제초제 등에 의해서는 유도되지 않고 Elicitor에 의해서만 특이하게 유도되는 것으로 나타나 Phytoalexin 생합성에 관여하는 유전자임을 확인하였다. Cyt P450 억제제인 ancy-midol과 ketoconazol에 의해 CYP-B3의 전사는 억제되지 않는 반면 5-epi-aristolochene hydroxylase의 효소활성은 현저히 억제되는 것으로 나타나 이들 억제제는 전사후의 효소의 합성 또는 활성을 억제하는 것으로 나타났다.

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Heterogeneous Natures of the Microbial Steroid $9{\alpha}$-Hydroxylase in Nocardioforms

  • Kang, Hee-Kyoung;Lee, Sang-Sup
    • Archives of Pharmacal Research
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    • 제20권6호
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    • pp.519-524
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    • 1997
  • Steroid $9{\alpha}$-hydroxylase is an enzyme found in nocardioform microorganisms which can utilize steroids as a sole carbon source. After fractional centrifugation of the cell homogenates, the enzyme activity in Nocardia and Rhodococcus was found in cytoplasmic membrane fraction. On the contrary, Mycobacterium had its 9.alpha.-hydroxylation activity in cytosolic fraction. To characterize the enzyme in these microorganisms, several potential inhibitors of 9.alpha.-hydroxylase were tested and the cofactor requirement for the same enzyme was also examined. The inhibitory effect of ferrous ion chelators indicated involvement of iron containing proteins in the 9.alpha.-hydroxylase system. On the other hand, metyrapone, an inhibitor known to be specific for cytochrome P450 interfered with the enzyme in Mycobacterium, but didn't inhibit the enzyme activity in Nocardia and Rhodococcus. While the $9{\alpha}$-hydroxylase system in Nocardia and Rhodococcus required NADPH, NADH was required as an election donor in Mycobacterium.

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A Study for Regulation of Ethanol-inducible $P_{450}$(CYP2E1) on $CCI_4$-induced Hepatic Damage

  • Park, Sun-Mi;Park, Eun-Jeon;Ko, Geon-Il;Kim, Jae-Baek;Sohn, Dong-Hwan
    • Archives of Pharmacal Research
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    • 제18권3호
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    • pp.179-182
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    • 1995
  • Previous study showed that $CCl_4$ administration evoked a rapid decrease in cytochrome $P_{450}$ 2E1 protein soon after the exposure due to posttranslational inhibition(Biochem. Biophys. Res. Commun. 179:449-454, 1991). In this report, aniline hydroxylase and the amounts of immunoreactive $P_{450}$ 2E1 were rapidly decreased during day 1 to 2 and recovered during day 3 to 4 after a single dose of $CCl_4$. The activity of pentoxyresorufin-O-dealkylase was also suppressed at day 1 and began to repair from day 2. However, the decrease in immunoreactive $P_{450}$ 2C content was not observed. The decreases in $P_{450}$ 2E1 enzyme activity and immunoreactive protein by acute $CCl_4$ treatment were accompanied by a decline in $P_{450}$ 2E1 mRNA level. The data thus suggested a pretranslational reduction of $P_{450}$ 2E1 during day 1 to 2 after acute $CCl_4$ treatment.

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Effects of Hydroxylated Flavonoids on the Ethoxyresorufin O-deethylase and Benzo($\alpha$)pyrene Hydroxylase

  • Sun, Sun-Ho;Sheen, Yhun-Yhong
    • Archives of Pharmacal Research
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    • 제19권6호
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    • pp.514-519
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    • 1996
  • In order to understand the mechanism of action of flavonoids on the drug metabolizing enzyme, cytochrome P450IA1, this study was undertaken to examine the effect of chrysin, morin, myricetin and aminopyrine on the activities of ethoxyresorufin O-deethylase and benzo(.alpha.) pyrene hydroxylase in the liver. In the isolated perfused rat liver that was pretreated with 3-methylcholanthrene (3MC), chrysin, morin, myricetin and aminopyrine inhibited the activity of ethoxyresorufin O-deethylase with concentration dependent manner. The isolated liver perfusion with chrysin, morin, myricetin and aminopyrine showed inhibition on the induction of ethoxyresorufin O- deethylase by 3MC. And also, in mouse liver hepa I cells, 3MC-stimulated the benzo(.alpha.)pyrene hydroxylase activity which was inhibited by chrysin, morin, myricetin and aminopyrine. These results strongly suggested that hydoxylated flavonoids interfered not only the induction of cytochrome P45OIA1 enzymes by 3MC but also the interaction of substrates and enzyme.

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고려인삼의 폴리아세틸렌 성분이 과산화 지질 형성에 미치는 영향 (Effect of Polyacetylene Compounds from Korean Ginseng on Lipid Peroxidation)

  • 김혜영;이유희;김신일;진승하
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1988년도 학술대회지
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    • pp.81-86
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    • 1988
  • 고려인삼에서 분리한 폴리아세틸렌 성분인 파낙시돌, 파낙시놀과 파낙시트리올의 사염화탄소로 유도된 마우스와 흰주의 지질과 산화와 효소적 또는 비효소적으로 유도된 시험관내 과산화 지질 형성에 미치는 영향을 관찰하였다. 정상 또는 사염화탄소 처리된 마우스와 흰쥐에 대한 폴리아세틸렌의 효과를 혈청과 간 과산화 지질수준과 혈청효소 (GOT, GPT, LDH) 활성을 측정함으로써 관찰하였다. 간 마이크로좀 내 cytochrome P-450 함량과 aniline hydroxylase와 aminopyrine demethylase 활성도 측정되었다. 정상 마우스에 폴리아세틸렌을 처리한 경우 파낙시놀의 경우를 제외하곤 간과 혈청의 과산화 지질 형성과 혈청효소들의 활성에 변화가 없었으며, 파낙시놀은 간의 지질 과산화를 억제하였다, 폴리아세틸렌 성분들은 사염화탄소로 유도된 간의 과산화지질형성에 대한 보호작용을 나타내었고, 혈청지질과산화 수준을 낮추었다. 또한 사염화탄소로 유도된 LDH의 혈액내 유출에 대한 보호작용이 있으나, 혈청 GOT와 GPT 수준엔 영향을 주지 않았다. 사염화탄소는 cytochrome P-450 함량과 aniline hydroxylase, aminopyrine demethylase 활성을 낮추었으며, 이 경우 폴리아세틸렌은 효과를 나타내지 못하였다. 반면, 사염화탄소 없이 폴리아세틸렌만 처리한경우, 파낙시돌과 파낙시놀은 aniline hydroxylase를 세폴리아세틸렌성분은 aminopyrine demethylase를 유도하였으며, cytochrome P-450엔 영향을 주지 않았다. 시험관내 간 마이크로좀의 지질 과산화는 폴리아세틸렌 첨가시 농도에 비례하여 억제되었다.

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벼에서 Bentazon 히드록시화반응에 관련된 Cytochrome P-450 활성(活性) 증진(增進)에 관한 연구(硏究) (The Enhancement of Cytochrome P-450 Mediated Aryl Hydroxylation of Bentazon in Rice Microsomes)

  • 변종영;넬슬 발키
    • 한국잡초학회지
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    • 제17권1호
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    • pp.59-65
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    • 1997
  • Bentazon이 첫 분해대사물질인 6-hydroxy bentazon으로 변화하는데 관련하는 cytochrome P-450 활성을 증진시키는 방법을 모색하기 위하여 벼 microsome에서 hydroxylase 효소 유기물질을 처리하여 bentazon 6-hydroxylase(B6H)와 식물에서 흔히 볼 수 있는 cinnamic acid 4-hydroxylase(CA4H) 효소를 대조하여 효소활성을 검정하였다. 1,8-naphthalic anhydride 0.5-2% 농도를 벼 종자에 분의처리하거나 fenclorim 5, 10${\mu}M$을 벼종자에 침지처리함에 따라 B6H와 CA4H 효소 활성이 증대되었다. Ethanol 2.5%를 벼 유묘에 처리함으로써 B6H와 CA4H 활성이 증대되었으며, phenobarbital 12mM 처리에서 B6H 활성이 증대되었고 phenobarbital 2mM 처리에서는 CA4H 활성이 증대되었다. B6H 효소활성은 ethanol 2.5, 5%와 phenobarbital 8, 12mM 혼합 처리 또는 1,8-naphthalic anhydride 0.5, 1%와 phenobarbital 8, 12mM 혼합처리에서 상승적으로 증가하였으며, CA4H 효소는 혼합처리에 의하여 활성이 저하되었다. 한편 벼 5 일묘에서는 B6H와 CA4H 활성 이 가장 높았으며 묘령이 진전될수록 효소활성은 현저히 감소되는 경향을 나타냈다.

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쇠무릎(Achyranthes japonica Nakai)으로부터 Ecdysteroid 생합성에 관련된 유전자의 분리 (Isolation of Genes Involved in Ecdysteroids Biosynthesis from Achyranthes japonica Nakai)

  • 부경환;김소미;진성범;채현병;이도승;김대운;조문제;류기중
    • Applied Biological Chemistry
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    • 제44권3호
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    • pp.153-161
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    • 2001
  • Ecdysteroid 생합성에 관련된 식물 유전자를 분리할 목적으로 ecdysteroid 생성능이 확인된 쇠무릎(Achyranthes japonica Nakai)으로부터 RNA를 분리하고, ecdysteroid 생합성에 관여한다고 알려진 cytochrome P45O family 유전자 4개와 곤충의 ecdysone 20-hydroxylase 유전자의 다중정렬 분석결과를 토대로 상동성이 높은 부위의 염기서열에 상응하는 degenerate primer를 사용하여 RT-PCR을 행하고, 고유한 염기서열을 가진 partical cDNA clone 14개를 선발했다. 기존에 ecdysteroid 생합성에 관여한다고 알려진 cytochrome P450 family 유전자들과의 염기 및 아미노산 서열의 상동성을 분석한 결과, 선발된 cDNA 중 6개가 cytochrome P45O fumily 유전자들과 상동성이 있는 것으로 나타났다. 이 중에서 4개의 clone은 곤충의 ecdysone 20-hydroxylase 유전자와도 상동성이 높아 ecdysteroid 생합성에 관련된 유전자로 추정되었다.

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반복적인 Betaine 투여가 간독성 및 Cytochrome P-450 의존성 약물대사효소계 활성에 주는 영향 (The Effect of Repeated Betaine Treatment on Hepatotoxicity and Cytochrome P-450 Dependent Drug Metabolizing Enzyme System)

  • 김상겸;김영철
    • 약학회지
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    • 제40권4호
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    • pp.449-455
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    • 1996
  • Betaine is one of the major water-soluble components in Lycii Fructus. In the present study the effect of repeated betaine treatment on the hepatotoxicity and the cytochrome P-4 50-dependent enzyme system was examined in adult female rats. Administrations of betaine (100 or 1,000mg/kg/day, ip) to rats repeatedly for 4 or 9 days did not evoke hepatotoxic response as determined by increases in glutamic pyruvic transaminase(GPT) and glutamic oxaloacetic transaminase(GOT) activities measured 24 hours following the final dose of betaine. The activities of aminopyrine N-demethylase, p-nitroanisole O-demethylase and p-nitrophenol hydroxylase as well as the contents of cytochrome P-450 were determined in hepatic microsomes of rats treated with betaine(1,000mg/kg/day, ip) for 4 or 9 days. Repeated treatment of rats with betaine for a period of 4 days induced a marginal decrease in the contents of cytochrome P-450, but did not influence the activities of p-nitrophenol hydroxylase, p-nitroanisole O-demethylase, or aminopyrine N-demethylase. Extension of the betaine treatment to 9 consecutive days failed to alter the parameters for hepatic drug metabolizing activity determined in the present study. Since repeated large doses of betaine were demonstrated to be tolerated by rats without showing any toxicity or changes in drug metabolizing enzyme activities in the liver, this compound appears to be relatively safe to animals upon long-term ingestion.

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