D, L-ATC로부터 L-Cysteine으로의 Bioconversion에 관여하는 효소의 특성

류옥희,신철수 한국산업미생물학회 1990 한국미생물·생명공학회지 Vol.18 No.1

D, L-2-aminothiazoline-4-carboxylic acid(D, L-ATC)로부터 L-cysteine으로의 bioconversion에 대한 특성을 살펴보았다. Pseudomonas species의 배양중에 D, L-ATC를 첨가하여 균체내에 그 관여되는 효소를 유도, 생성시키고 균체만을 모은 후 파쇄하여 조효소액으로 조제하였다. 실험결과, D, L-ATC로부터 L-형의 cysteine만이 생성되며, 이 반응에 관여되는 효소는 cofactor로서 Mn이온을 필요로 하며, Mn이온의 첨가에 의해 L-cysteine의 생성량이 수십배 증가되었다. 그러나, 이 효소는 생성물인 L-cysteine에 의해 feedback inhibition을 받았다. 한편, L-cysteine의 분해효소가 조효소액 내에 존재하며 그 효소반응의 저해제없이는 생성된 L-cysteine의 대부분이 분해되었다. 반면, 매우 효과적인 효소저해제인 hydroxylamine의 첨가로 L-cysteine의 분해를 거의 방지할 수 있었다. The bioconversion of D, L-2-aminothiazoline-4-carboxylic acid(D, L-ATC) to L-cysteine was investigated. After the intracellular enzyme of a Pseudomonas species was inducibly formed by addition of D, L-ATC in the middle of culture, the cells were isolated and treated with sonication to prepare the crude enzyme solution. The results indicated that the cysteine was produced only in the form of L-isomer from D, L-ATC and its production could be enhanced several tens times by addition of managanese ions which were required as a cofactor in this enzymatic reaction. Besides, this r-action suffered from the feedback inhibition of L-cysteine. On the other hand, since L-cysteine-decomposing enzyme coexisted in the crude enzyme solution, most of the L-cysteine formed disappeared in the absence of its inhibitor. However, hydroxylamine was found to be a potent inhibitor which could successfully prevent the decomposition of L-cysteine.

D,L-ATC로부터 L-Cysteine으로의 효소적 전환에 관한 동력학적 연구

류옥희,신철수 연세대학교 산업기술연구소 1991 논문집 Vol.23 No.2

The conversion of D,L-2-amino-△²-thiazoline-4-carboxylic acid(D,L-ATC) to L-cysteine via S-carbamyl-L-cysteine as an intermediate between them consists of two steps and is carried out by the enzymes produced in Pseudomonas sp. And L-cysteine can be enzymatically degraded. By simulating the experimental data obtained in each reaction to the corresponding model equation, values of kinetic parameters such as reaction rate constants are estimated, respectively. And, by applying these values to the overall kinetic equations, the patterns of each compound on time are again predicted. Comparisions of the experimental profiles with the calculated (or predicted) ones suggest that other intermediates will exist between the D,L-ATC and S-carbamyl-L-cysteine.

사람 Low Density Lipoprotein (LDL)에 대한 Rooibos tea의 항산화 활성

조경자,김희숙,박종옥,류병호 경성대학교 2001 論文集 Vol.22 No.1

This study was investigated to antioxidative activity of crude catechin extracted from Rooibos tea against low density lipoprotein(LDL) oxidation. The crude catechin inhibited the copper-mediated oxidation of human LDL at the concentrations of 50 and 100 ㎍/㎖ in the presence of 5 μM CuSO4. The crude catechin also inhibited LDL oxidation induced by macrophage J774 cell. LDL oxidized by copper mediated and cell induced oxidation was degraded by macrophage at a much greater rate than native LDL. The electrophoretic mobility of oxidized LDL by addition of crude catechin was faster than that of native LDL. The results provided a possibility that crude catechin of Rooibos tea might protect LDL against oxidation in atheroscleotic lessions.

구개부에 발생한 다형선종의 처치

하주원,백승,송종운,박충열,이용욱,박홍주,오희균,유선열,김옥준 大韓顎顔面成形再建外科學會 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.6

Pleomorphic adenoma of the palate is the most common of all intraoral salivary tumors. It can occur at any age but it presents most commonly in the 40∼60 age group, and there is no significant sex preponderance. It grows slowly and is usually painless, firm, well-circumscribed nodule. Because of high rate of recurrence, extra-capsular excision including the overlying mucosa and margin of normal tissue is recommended. We report 10 cases of palatal pelomorphic adenoma which have been successfully treated by extra-capsular excision. The surgical defects smaller than 3㎝ in diameter were covered with palatal acrylic splint for the secondary healing. The larger defects were repaired using palatal island flap in 3 cases, rotation flap and buccal fat graft in each 1 case. No patient showed any recurrence or malignant change during the mean follow-up period of 4 years and 9 months. These repair methods seem to be simple, reliable and uncomplicated procedures in the palatal surgical defects.

Analysis of the Reaction Steps in the Bioconversion of D,L-ATC to L-Cysteine

Ryu, Ok Hee,Shin, Chul Soo 한국미생물 · 생명공학회 1991 Journal of microbiology and biotechnology Vol.1 No.1

The reaction steps involved in the bioconversion of a chemically synthesized precursor, D,L-2-amino-Δ^2-thiazollne-4-carboxylic acid (D,L-ATC), to L-cysteine and the properties of the involved enzymes were investigated. It was found that the conversion consisted of two steps, i. e., D,L-ATC to S-carbamyl-L-cysteine (S-C-L-cysteine) and S-C-L-cysteine to L-cysteine, and the S-C-L-cysteine was an intermediate between them. While the enzymes involved in the reactions were induced by the addition of D,L-ATC as an inducer, S-C-L-cysteine induced only the enzyme involved in the latter step. The conversion of S-C-L-cysteine to L-cysteine could be also carried out in the presence of hydroxylamine and its rate was much faster than that by the corresponding enzyme. On the other hand, L-cysteine (or L-cystine) was decomposed to evolve H_2S by the enzyme considered to be a kind of desulfhydrase. However, hydroxylamine was a perfect inhibitor for this enzyme.

Mutant p53-Notch1 Signaling Axis Is Involved in Curcumin-Induced Apoptosis of Breast Cancer Cells

Yun-Hee Bae,Jong Hyo Ryu,Hyun-Joo Park,Kwang Rok Kim,Hee-Jun Wee,Ok-Hee Lee,Hye-Ock Jang,Moon-Kyoung Bae,Kyu-Won Kim,Soo-Kyung Bae 대한생리학회-대한약리학회 2013 The Korean Journal of Physiology & Pharmacology Vol.17 No.4

Notch1 has been reported to be highly expressed in triple-negative and other subtypes of breast cancer. Mutant p53 (R280K) is overexpressed in MDA-MB-231 triple-negative human breast cancer cells. The present study aimed to determine whether the mutant p53 can be a potent transcriptional activator of the Notch1 in MDA-MB-231 cells, and explore the role of this mutant p53-Notch1 axis in curcumin-induced apoptosis. We found that curcumin treatment resulted in an induction of apoptosis in MDA-MB-231 cells, together with downregulation of Notch1 and its downstream target, Hes1. This reduction in Notch1 expression was determined to be due to the decreased activity of endogenous mutant p53. We confirmed the suppressive effect of curcumin on Notch1 transcription by performing a Notch1 promoter-driven reporter assay and identified a putative p53-binding site in the Notch1 promoter by EMSA and chromatin immunoprecipitation analysis. Overexpression of mutant p53 increased Notch1 promoter activity, whereas knockdown of mutant p53 by small interfering RNA suppressed Notch1 expression, leading to the induction of cellular apoptosis. Moreover, curcumin-induced apoptosis was further enhanced by the knockdown of Notch1 or mutant p53, but it was decreased by the overexpression of active Notch1. Taken together, our results demonstrate, for the first time, that Notch1 is a transcriptional target of mutant p53 in breast cancer cells and suggest that the targeting of mutant p53 and/or Notch1 may be combined with a chemotherapeutic strategy to improve the response of breast cancer cells to curcumin.

연구 논문 : 인공 먼지로서 단분산 Polystyrene Latex Spheres (PLS)의 제조

김옥희 ( Ok Hee Kim ),류동완 ( Dong Wan Ryu ),성동찬 ( Dong Chan Sung ),문희 ( Hee Moon ) 한국공업화학회 2012 공업화학 Vol.23 No.1

potassium persulfate (KPS)와 sodium dodecyl sulfonate (SDS)를 각각 개시제와 안정제로 사용한 유화중합에 의하여 인공 먼지로 사용할 수 있는 polystyrene latex spheres (PLS)를 제조하였다. PLS입자의 크기를 조절하기 위한 변수로 반응온도와 개시제 및 안정제의 농도가 선택되었다. 반응온도의 증가에 따라 입자의 크기는 작아졌으며, KPS와 SDS의 농도를 변화시켜 PLS 입자의 크기 및 분포를 매우 미세하게 조절할 수 있었다. 본 연구에서 제조된 PLS입자는 변동계수(CV) 값이 7% 이하인 단분산이며, 0.1∼0.5 μm 범위에 있어 인조 먼지로 사용하기에 적합한 것으로 밝혀졌다. Polystyrene latex spheres (PLS) were prepared as artificial dusts by the emulsion polymerization with potassium persulfate (KPS) and sodium dodecyl sulfonate (SDS) as an initiator and a stabilizer, respectively. The reaction temperature and the concentration of the initiator and stabilizer were chosen as variables to control the PLS particle size. As temperature increased, the particle size decreased considerably. Furthermore, the PLS particle size and their size distributions can be controlled minutely by adjusting the concentrations of KPS and SDS. It is confirmed that the PLS prepared in this work is monodispersed with the coefficient of variance less than 7% and are in the range of 0.1∼0.5 μm, which are good for using as artificial dusts.

8-Oxo-7,8-dihydroguanosine triphosphate(8-oxoGTP) down-regulates respiratory burst of neutrophils by antagonizing GTP toward Rac, a small GTP binding protein

Kim, Hee Joon,Yoon, Sun-Hee,Ryu, Hyun-Ok,Yoon, Byung-Hak,Choi, Seongwon,Ye, Sang-Kyu,Chung, Myung-Hee Harwood Academic 2007 Free radical research Vol.41 No.6

<P> 8-Oxo-7,8-dihydroguanosine triphosphate (8-oxoGTP) has been regarded simply as a oxidative mutagenic byproduct. The results obtained in this study imply that it may act as a down-regulator of respiratory burst of neutrophils. Human neutrophils treated with PMA produced superoxides and at the same time, the cytosol of these cells was intensely immunostained by 8-oxo-7,8-dihydroguanosine(8-oxoG) antibody, indicating that 8-oxoG-containing chemical species including 8-oxoGTP are produced. Human neutrophil lysates treated with PMA also produced superoxides, which was stimulated by GTP&ggr;S but inhibited by 8-oxoGTP&ggr;S. Moreover, 8-oxoGTP&ggr;S suppressed the stimulatory action of GTP&ggr;S. Likewise, GTP&ggr;S stimulated Rac activity in neutrophil lysates but 8-oxoGTP&ggr;S and GDP inhibited it. The inhibitory effect of GDP was one tenth that of 8-oxoGTP&ggr;S. Here again, 8-oxoGTP&ggr;S also suppressed the stimulatory action of GTP&ggr;S on Rac activity. These results imply the possibility that 8-oxoGTP is formed during respiratory burst of neutrophils and limits neutrophil production of superoxides by antagonizing GTP toward Rac.</P>

일 지역 대사증후군 위험인자와 건강행태에 관한 연구

안옥희(Ahn, Ok-hee),최성희(Choi Seong-hui),김서현(Kim, Seo-Hyeon),류시옥(Ryu, Si-Ok),최영미(Choi, Young-Mi) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.12

최근 우리나라는 사회 · 경제적으로 급성장하면서 생활습관과 질병양상이 다양하게 변화하여 만성질환 발병에 중대위협을 받고 있다. 특히 만성질환의 원인요소를 공통적으로 포함하고 있는 대사증후군의 위험요인은 예방관리가 시급하며 우리나라 성인의 대사증후군 유병률은 22.4%로 많은 비중을 차지하고 있다. 본 연구는 SPSS 23.0을 사용하여 2014년 지역사회건강조사 원시자료 12,481명 중 충실히 응답된 전라북도 대상자 12,185명을 분석하였다. 대상자의 건강행태의 특성에 따른 대사증후군 위험요인 유무 차이는 성별, 흡연, 연령, 교육수준, 격렬한 신체활동 일수 등에서 유의하게 나타났다. 본 연구는 대사증후군 위험요인 중 이상지혈증, 고혈압 및 당뇨가 있는 집단에게 음주, 흡연 및 격렬한 신체활동 요인에 관한 건강증진프로그램의 참여를 활성화 시키는 방안이 필요함을 강조하고 있다. 이에 본 연구는 일 지역 대사증후군 위험요인과 건강행태를 분석하여 건강생활실천 요소를 규명하고 건강증진 활성화에 기여하는 기초자료로 제공하고자 한다. Recently, Korea has undergone rapid social and economic development, and with that came various changes in living habits and disease patterns; the nation, accordingly, has been alerted to the associated risks of chronic ailments. As risk factors of metabolic syndrome commonly include causal factors of chronic diseases, prevention is important. The prevalence of metabolic syndrome in Korean adults is 22.4%, which comprises a large portion of the whole disease (Korean National Health and Nutrition Examination Survey, 2013). This study aims to examine the elements of healthy living practices by analyzing the risk factors of metabolic syndrome and health behaviors, and provide basic materials to contribute to the activation of health promotion. Among 12,481 subjects of the source data from the 2014 community health survey, which was performed on adults aged 19 and over in Jeonlabuk-do, 12,185 people were analyzed in this study using SPSS 23.0. There were significant differences with respect to sex, smoking status, age, education level, and number of days of physical activity among the results of the difference of the risk factors of the metabolic syndrome according to the characteristics of the health behavior of the subjects . Of the risk factors for metabolic syndrome, this study emphasized the necessity of strategies to promote health programs regarding the management of drinking, smoking, physical activities, depression, subjective health condition and quality of life to the group of those with dyslipidemia, hypertension, and diabetes.

Mutant p53-Notch1 Signaling Axis Is Involved in Curcumin-Induced Apoptosis of Breast Cancer Cells

Bae, Yun-Hee,Ryu, Jong Hyo,Park, Hyun-Joo,Kim, Kwang Rok,Wee, Hee-Jun,Lee, Ok-Hee,Jang, Hye-Ock,Bae, Moon-Kyoung,Kim, Kyu-Won,Bae, Soo-Kyung The Korean Society of Pharmacology 2013 The Korean Journal of Physiology & Pharmacology Vol.17 No.4

Notch1 has been reported to be highly expressed in triple-negative and other subtypes of breast cancer. Mutant p53 (R280K) is overexpressed in MDA-MB-231 triple-negative human breast cancer cells. The present study aimed to determine whether the mutant p53 can be a potent transcriptional activator of the Notch1 in MDA-MB-231 cells, and explore the role of this mutant p53-Notch1 axis in curcumin-induced apoptosis. We found that curcumin treatment resulted in an induction of apoptosis in MDA-MB-231 cells, together with downregulation of Notch1 and its downstream target, Hes1. This reduction in Notch1 expression was determined to be due to the decreased activity of endogenous mutant p53. We confirmed the suppressive effect of curcumin on Notch1 transcription by performing a Notch1 promoter-driven reporter assay and identified a putative p53-binding site in the Notch1 promoter by EMSA and chromatin immunoprecipitation analysis. Overexpression of mutant p53 increased Notch1 promoter activity, whereas knockdown of mutant p53 by small interfering RNA suppressed Notch1 expression, leading to the induction of cellular apoptosis. Moreover, curcumin-induced apoptosis was further enhanced by the knockdown of Notch1 or mutant p53, but it was decreased by the overexpression of active Notch1. Taken together, our results demonstrate, for the first time, that Notch1 is a transcriptional target of mutant p53 in breast cancer cells and suggest that the targeting of mutant p53 and/or Notch1 may be combined with a chemotherapeutic strategy to improve the response of breast cancer cells to curcumin.