• Environmental Analysis Health and Toxicology
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• 제7권1_2호
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• pp.1-16
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• 1992

Biologically, MGK-264 (N-octyl bicycloheptene dicarboximide) acts as a synergists for insecticides mainly pyrethrins and pyrethroids. It's used extensively in combination with pyrethrin and piperonyl butoxide and also with personal insect repellent and cockroach repellents. But the toxic effect of MGK-264 in mamalians was a relatively little known therefore in this studies it was initiated to examine the toxic effect of MGK -264 in rats. For 5 weeks it administrated daily in each 250 mg and 500 mg of MGK-264 per kg of body weight in rats. 1) The body weight gain and the LYMPH (%) value in blood were observed a slight tendency to reduce in accordance with amount of dose and number treatment time. 2) The content of cytochrome P-450 and activity of NADPH-cytochrome c reductase were decreased in liver and those were observed some tendency in the kidney as liver but not significant. 3) The liver cholinesterase activity in the both 250 mg/kg and 500 mg/kg per kg of body weight with treated groups and the liver aniline hydroxylase in 500 mg/kg treated group were gradually decreased from 4 weeks after treated groups. In consequence it would sugested that the toxic effect of MGK-264 was low but in could offer hazard effect in liver and nervers system of rats if it was administrated move dose of MGK-264 and agumented in number of treated time.

• Journal of Microbiology and Biotechnology
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• 제22권8호
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• pp.1059-1065
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• 2012

Biocatalytic transfer of oxygen in isolated cytochrome P450 or whole microbial cells is an elegant and efficient way to achieve selective hydroxylation. Cytochrome P450 CYP105P2 was isolated from Streptomyces peucetius that showed a high degree of amino acid identity with hydroxylases. Previously performed homology modeling, and subsequent docking of the model with flavone, displayed a reasonable docked structure. Therefore, in this study, in a pursuit to hydroxylate the flavone ring, CYP105P2 was co-expressed in a two-vector system with putidaredoxin reductase (camA) and putidaredoxin (camB) from Pseudomonas putida for efficient electron transport. HPLC analysis of the isolated product, together with LC-MS analysis, showed a monohydroxylated flavone, which was further established by subsequent ESI/MS-MS. A successful 10.35% yield was achieved with the whole-cell bioconversion reaction in Escherichia coli. We verified that CYP105P2 is a potential bacterial hydroxylase.

• 환경생물
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• 제26권2호
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• pp.94-101
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• 2008

공장 폐수로 인한 오염이 심한 경기 시화호에서 오염정도가 다른 두 지역으로부터 풀망둑을 채집하여 이들의 해독효소계 또는 항산화효소계의 반응을 비교하였다. 해독효소계에서 I상효소로는 CYP, P450R, b5R, EROD를, II상효소로는 GST를 조사하였다. 그리고 항산화효소계로는 CAT, GR, CPx의 활성 그리고 GSH및 CSSG농도를 조사하였다. 그 결과, 오염정도가 심한 지역에서 잡은 어류가 간장 중 P450R, b5R, GST의 활성이 높았으나 EROD활성은 오히려 낮았고 CYP농도는 차이가 없었다. 그리고 이지역에서 잡은 어류는 CAT와 GR의 활성, 비효소적인 항산화계인 CSH와 GSSC농도도 더 높았으나 GTx활성은 오히려 낮았다. 이들 결과는 시화호의 오염된 곳에서 서식하는 풀망둑 Acanthogobius hasta은 상당히 해독효소계가 항진되어 있으며 산화 스트레스도 크게 받고 있음을 보여준다.

• 한국환경성돌연변이발암원학회지
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• 제22권3호
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• pp.169-174
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• 2002

Resveratrol is known to have potent cancer chemopreventive activity against tumorigenesis caused by 7,12-dimetylbenz［$\alpha$］anthracene(DMBA) which is known to be oxidized to reactive products by cytochrome P450 1B1 (CYP1B1). The effects of resveratrol on the activity of recombinant human P450 1 family enzymes, expressed in Escherichia coli membranes with human NADPH-P450 reductase, were determined by measuring alkoxyresorufin O-dealkylation activity, e.g., ethoxyresorufin O-deethylation (EROD) CYP1A1, methoxyresorufin O-demethylation (MROD), CYP1A2, benzyloxyresorufin-O-debenzylation (BROD), CTP1B1. Resveratrol inhibited CYP1B1 and CYP1A1 activities in a dose-dependent manner with $IC_{50}$/ values of 59 and 10$\mu$M for EROD activity and 1.8 and 30$\mu$M for BROD activity, respectively. Resveratrol had only weak inhibitory effect on CYP1A2 activity ($IC_{50}$/ values of 0.44 mM for EROD and ＞2 mM for MROD). Furthermore, resveratrol did not affect NADPH-P450 reductase activity significantly. Resveratrol inhibited the CYP1B1-dependent EROD activity with a $K_{i}$ of 28 $\mu$M in a non-competitive type manner. these results suggest that resveratrol-derived inhibited of CYP1B1 and CYP1A1 activities may contribute to the suppression of DMBA inducible tumorigenesis observed in extrahepatic tissues.s.

• Archives of Pharmacal Research
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• 제26권1호
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• pp.47-52
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• 2003

The aim of this study was to investigate the effects of trauma on alterations in cytochrome P450 (CYP 450)-dependent drug metabolizing function and to determine the role of Kupffer cells in hepatocellular dysfunction. Rats underwent closed femur fracture (FFx) with associated soft-tissue injury under anesthesia, while control animals received only anesthesia. To deplete Kupffer cells in vivo, gadolinium chloride (GdCl$_3$) was injected intravenously via the tail vein at 7.5 mg/kg body wt., 1 and 2 days prior to FFx surgery. At 72 h after FFx, serum alanine aminotransferase (ALT) activity was increased, and this increase was attenuated by GdCl$_3$ pretreatment. Serum aspartate aminotransferase (AST) and lipid peroxidation levels were not changed by FFx. Hepatic microsomal CYP 450 content and aniline p-hydroxylase (CYP 2E1) activity were significantly decreased; decreases that were not prevented by GdC1$_3$. The level of CYP 2B1 activity was decreased by Kupffer cell inactivation, but not by FFx. There were no significant differences in the activities of CYP 1A1, CYP 1A2 and NADPH-CYP 450 reductase among any of the experimental groups. Our findings suggest that FFx trauma causes mild alterations of hepatic CYP 450-dependent drug metabolism, and that Kupffer cells are not essential for the initiation of such injury.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.295-298
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• 2006

Actinomycetes are ubiquitous Gram-positive soil bacteria and a group of the most important industrial microorganisms for the biosynthesis of many valuable secondary metabolites as well as the source of various bioconversion enzymes. Cytochrome P450 hydroxylase (CYP), a hemebinding protein, is known to be involved in the modification of various natural compounds, including polyketides, fatty acids, steroids, and some aromatic compounds. Previously, six different novel CYP genes were isolated from a rare actinomycetes called Sebekia benihana, and they were completely sequenced, revealing significant amino acid similarities to previously known CYP genes involved in Streptomyces secondary metabolism. In the present study, these six CYP genes were functionally expressed in Streptomyces lividans, using an $ermE^{*}$ promoter-containing Streptomyces expression vector. Among six CYP genes, two S. benihana CYP genes (CYP503 and CYP504) showed strong hydroxylation activities toward 7-ethoxycoumarin. Furthermore, the recombinant S. lividans containing both the S. benihana CYP506-ferredoxin genes as well as the S. coelicolor feredoxin reductase gene also demonstrated cyclosporin A hydroxylation activity, suggesting potential application of actinomycetes CYPs for the biocatalysts of natural product bioconversion.

• 한국발생생물학회지:발생과생식
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• 제11권3호
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• pp.187-193
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• 2007

Ethane 1,2-dimethane sulfonate(EDS)는 Leydig 세포의 선별적 사멸을 유도하는 약물로서 가역적인 테스토스테론 결핍 흰쥐를 만드는데 널리 사용된다. 부정소의 구조와 기능 유지는 크게 보아 정소에서 분비되는 테스토스테론에 의존적이지만, 테스토스테론으로부터 유도되는 dihydroxytestosterone(DHT)와 에스트로겐도 중요한 역할을 한다. 본 연구에서는 EDS 주사 후 7주까지 부정소에서의 스테로이드 호르몬 수용체, cyctochrome P450aromatase(P450arom)와 $5{\alpha}$-reductase의 유전자 발현 양상을 조사하였다. 성숙한 수컷 흰쥐($350{\sim}400\;g$)에 EDS를 1회 복강 주사하고(75 mg/kg i.p.) 주사 후 0, 1, 2, 3, 4, 5, 6, 7주가 경과한 날에 희생하였다. 표적 유전자들의 전사 활성은 반 정량적 역전사 중합효소 반응법(semi-quantitative RT-PCRs)으로 측정하였다. Estrogen receptor alpha($ER{\alpha}$) 전사 수준은 EDS 실험군에서 대조군에 비해 주사 1주후에 유의하게 상승했으나(P<0.01) 2주 후부터는 대조군과 유의적인 차이를 보이지 않았다. Estrogen receptor beta($ER{\beta}$)의 전사 수준은 주사 1주후 EDS 실험군에서 대조군에 비해 유의하게 증가했다가(P<0.05), 2주와 3주에는 감소하였고(P<0.05와 P<0.01), 4주와 6주까지는 변동폭을 보이다가 7주 후에는 대조군에 비해 증가하였다(P<0.05). Androgen receptor(AR) 전사 수준은 주사 2주 후에 유의하게 증가하다가(P<0.01) 3주 후부터는 대조군 수준으로 회복하였다. 반면, P450arom는 주사 1주 후부터 3주까지 급격하게 감소했다가(P<0.01 1주와 2주; P<0.05 3주), 4주에 대조군 수준으로 회복하였다. $5{\alpha}$-reductase type 2($5{\alpha}$-RT2)의 mRNA 수준은 4주 후 유의하게 증가했다가(P<0.01), 이후 대조군 수준으로 회복하였다. 본 연구는 EDS 주사가 성 스테로이드 호르몬 수용체들과 안드로겐 전환 효소들의 전사 활성에 가역적인 변화를 유도함을 보여준 것이다. EDS 주사 모델은 부정소의 생리 조절 기작을 이해하는데 유용할 것으로 사료된다.

• 한국환경성돌연변이발암원학회지
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• 제23권3호
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• pp.94-98
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• 2003

Quercetin and naringenin are representative flavonoids that not only exert anti estrogenic, cholesterol-lowering and antioxidant activities but also can modulate the metabolism of many xenobiotics. The activity of the specific form(s) of CYP450 is likely to be a major determinant of susceptibility to chemically induced carcinogenesis between which varies among between individuals due to different dietary habits as well as genetic characteristics. People consume cooked meat or fish together with various vegetables containing substantial amounts of quercetin and naringenin that can modify the enzyme activity of CYP1A2 to stimulate or to inhibit the mutagenic activities of HCAs. Heterocyclic amines (HCAs) produced by cooking meat products at high temperatures are promutagens that are activated by cytochrome P450 (CYP) lA2. Using a newly developed Salmonella typhimurium TA1538/1A2bc-b5 strain, we tested the effect of quercetin and naringenin on the mutagenicity of 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ). TA1538/1A2bc-b5 bears two plasmids, one expressing human CYP1A2 and NADPH-P450 reductase (NPR), and the other plasmid which expresses human cytochrome b5 (cyp b5). TA1538/1A2bc-b5 cells showed high activities of 7-ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) associated with CYP1A2 and are very sensitive to mutagenesis induced by several HCAs. MeIQ was found to be the strongest mutagen among the HCAs tested in this system. Mutagenicity of MeIQ was enhanced 50 and 42% by quercetin at 0.1 and 1 mM, respectively, but suppressed 82% and 96% at 50 mM and 100 mM. Naringenin also increased the MeIQ-induced mutation about 37% and 22% at 0.1 and 1 mM, but suppressed it 32% and 63% at 50 mM and 100 mM concentrations, respectively, in TA 1538/1A2bc-b5 cells. Thus, they stimulated the MeIQ induced mutation at low concentrations, but strongly suppressed it at high concentrations. This biphasic effect of flavonoids was due to the stimulation or the inhibition of CYP1A2 activity in a dose-dependent manner judging by the activities of EROD or MROD in the Salmonella cells. Collectively, it is likely that the biphasic effects of quercetin and naringenin on the MeIQ-induced mutagenesis in S. typhimurium TA1538/CYP1A2bc-b5 were due to their differential modification of the CYP1A2 activity in these cells.

• ALGAE
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• 제30권3호
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• pp.233-239
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• 2015

Microalgae research is gaining momentum because of their potential biotechnological applications, including the generation of biofuels. Genome sequencing analysis of two model microalgal species, polar free-living Coccomyxa sp. C-169 and symbiotic Chlorella sp. NC64A, revealed insights into the factors responsible for their lifestyle and unravelled biotechnologically valuable proteins. However, genome sequence analysis under-explored cytochrome P450 monooxygenases (P450s), heme-thiolate proteins ubiquitously present in species belonging to different biological kingdoms. In this study we performed genome data-mining, annotation and comparative analysis of P450s in these two model algal species. Sixty-nine P450s were found in two algal species. Coccomyxa sp. showed 40 P450s and Chlorella sp. showed 29 P450s in their genome. Sixty-eight P450s (>100 amino acid in length) were grouped into 32 P450 families and 46 P450 subfamilies. Among the P450 families, 27 P450 families were novel and not found in other biological kingdoms. The new P450 families are CYP745-CYP747, CYP845-CYP863, and CYP904-CYP908. Five P450 families, CYP51, CYP97, CYP710, CYP745, and CYP746, were commonly found between two algal species and 16 and 11 P450 families were unique to Coccomyxa sp. and Chlorella sp. Synteny analysis and gene-structure analysis revealed P450 duplications in both species. Functional analysis based on homolog P450s suggested that CYP51 and CYP710 family members are involved in membrane ergosterol biosynthesis. CYP55 and CYP97 family members are involved in nitric oxide reduction and biosynthesis of carotenoids. This is the first report on comparative analysis of P450s in the microalgal species Coccomyxa sp. C-169 and Chlorella sp. NC64A.

• 약학회지
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• 제28권1호
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• pp.29-33
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• 1984

The paper aimed to review the influences of ginseng on the metabolism of foreign substances and on the activity of hepatic drug metabolizing enzyme system in mouse or rat liver. It has been known that ginseng components reduces the motality rates and the toxic effects induced by foreign materials. Chronic pretreatment of mouse or rat with ginseng extract fractions or saponin caused the increase in the metabolism of foreign materials and the activity of drug metabolizing enzymes, such as cytochrome $P_{450}$, NADPH cytochrome C reductase and glucuronyl S-transferase in liver. Thus, it may be concluded that decrease in toxic effect of foreign substances by ginseng pretreatment may be partly related to the induction of drug metabolizing enzymes in liver.