Pseudomonas sp. DJ-12의 pcbCD 유전자의 클로닝과 Escherichia coli에서의 발현

김치경,성태경,남정현,김영창,이재구,Kim, Chi-Kyung,Sung, Tae-Kyung,Nam, Jung-Hyun,Kim, Chang-Young,Lee, Jae-Koo 한국미생물학회 1994 미생물학회지 Vol.32 No.1

Polychlorinaed biphenyls(PCBs) 와 biphenyl을 분해하는 Pseudomonas sp. DJ-12에서는 그 초기 분해과정에 pcb ABCD 유전자들이 관여하고 있음이 밝혀졌다. 그 중 pcbCD와 pcdD 유전자를 E. coli XL1-Blue에 클로닝하여 E. coli CU103 과 CU105 균주를 각각 제조하였다. E. coli CU103은 2,3-dehydroxybuphenyl dioxygenase(2,3-DHBP)와 meta-cleavage compound(MCP) hydrolase를 생성하여 2,3-dihydroxybiphenyl을 benzoate로 변환시켜 주었다. E. coli CU1 과 CU103 에서 pcbC 유전자의 산물인 2,3-DHBP dioxygense의 활성도는 Pseudomonas sp. DJ-12에서 보다 약 17배 높았으며, E. coli CU105에서 pcbD의 산물인 MCP hydrolase는 약 3배 더 높게 나타났다. The pcb genes of Pseudomonas sp. DJ-12 coded for the catabolism of polychlorinated biphenyl (PCBs) and biphenyl. The products of the pcbCD genes were 2,3-dihydroxy-4'-chlorobiphenyl dioxygenase and meta-cleavage product (MCP) hydrolase, which acted on degradation of 2,3-dihydroxy-4'-chlorobiphenyl to 4-chlorobenzoate. The pcbCD genes were cloned in E. coli XLl-Blue, and then the pcbD gene was further subcloned. As a metabolite transformed from 2,3-dihydroxybiphenyl by the cloned cell of E coli CU103, benzoate was detected by the resting cell assay. The enzyme activities of 2,3-dihydroxybiphenyl dioxygease and MCP hydrolase produced in the cloned cells E. coli CU103 and CU105 were about 17 and 3 times higher than those of Pseudomonas sp. DJ-12, respectively.

Heparin-Protamin Sulfate 상호작용의 실험적 연구

김치경,이홍균,Kim, Chi-Kyung,Lee, Hong-Kyun 대한흉부심장혈관외과학회 1980 Journal of Chest Surgery (J Chest Surg) Vol.13 No.1

Heparin would have been used for preventing clotting of blood during extracorporeal circulation and subsequent use of protamine sulfate and made possible the neutralization of heparin. This procedure has been adopted for eliminating one of the great causes of bleeding, especially in cardiac surgery. In this experiment, the hypocoagulability of blood induced by heparin followed by neutralization with treatment of protamine sulfate were estimated by the Lee-White clotting time [CT], partial thromboplastin time [PTT] and protamine titration test. The results were as follows: 1] Comparison of clotting time between the heparinized [2.0 mg/kg] and non-heparinized dogs was done using CT and PT`I` of the blood. In heparinized group [Group I], the CT lasted infinitively and prolongation of PTT [4 times than normal] until 60 minutes. The CT [2 times] and PTT [3 times] has been shortened after 90 minutes, however they returned to normal limit level within 180 minutes. 2] The determination of appropriate ratio of heparin and protamine In vivo were performed. The group II [heparin 2.0 mg/kg, protamine 1.0 mg/kg] revealed rapid decrease of CT and PTT, but returned to normal after 120 minutes. The group III [heparin 2.0 mg/kg, protamine 2.0 mg/kg] returned rapidly to normal within 15 minutes. The group IV [heparin 2.0 mg/kg, protamine 3.0 mg/kg] recovered its normal level after 60 minutes. The group V [heparin 2.0 mg/kg, protamine 4.0 mg/kg] recovered its normal level after 90 minutes. 3] In the combined experimental study In vivo and vitro, the protamine titration test was done using the dog which were given 2.0 mg/kg and 3.0 mg/kg of heparin, respectively and coagulation time were checked after 15, 30, 60 and 120 minutes. The complete neutralization was showed to be heparin-protamine ratio of 1:1 to 1.5. 4] In vitro study, fresh blood was drawn into known amount of heparin content [20, 40, 60 and 100/ug per 1 ml of blood] syringe, thereafter protamine titration test was done. In all cases, the complete neutralization was found in heparin-protamine ratio of 1:0.85 to 1.5. 5] It was found by the present experiment that the ideal heparin-protamine ratio was 1:1 within 60 minutes and 1:0.5 after 60 minutes for avoiding the serious side effect due to overadministration of protamine sulfate.

Pseudomonas spp.에 의한 4-chlorobiphenyl의 분해 및 Plasmid와의 연관성

김치경,이익근,Kim, Chi-Kyung,Lee, Ik-Keun 생화학분자생물학회 1990 한국생화학회지 Vol.23 No.3

자연계로 부터 분리한 균주 중 4-chlorobiphenyl(4CB) 분해균주로 DJ-12, DJ-26, DJ-77, MS-1003 그리고 FP-6을 사용하여 4CB를 단일 탄소원으로 첨가한 최소배지에서 그들의 생장율과 4CB의 분해율을 조사하였다, DJ-12와 DJ-26 균주는 4CB를 분해할 때 236과 280 nm의 파장에서 각각 흡광하는 중간 대사산물들이 검정되는 것으로 보아 이 균주들은 meta-cleavage pathway에 의하여 4CB를 분해하여 meta-cleavage compound를 거쳐 4-chlorobenzoic acid(4CBA)를 생성한다는 것을 알 수 있었다. 또 DJ-12 균주가 단일 탄소원으로 4CB를 공급할 때 meta-cleavage pathway를 거쳐 retention time이 2.6~2.8 분대에서 검출되는 4CBA를 생성하는 것이 HPLC로 확인되었다. 그리고 DJ-12 균주와 P. putida KT2440을 in vivo cloning하여 얻은 transconjugant들로 부터 plasmid의 특성을 조사해 본 결과, DJ-12 균주에서 4CB 분해유전자가 약 65 kb 정도의 pDJ121 plasmid에 연관되어 있다는 것을 발견하였다. Including the Pseudomonas strains reported in the previous works, two bacterial strains which are able to degrade 4-chlorobiphenyl(4CB) were isolated from natural environments. They were investigated for their ability to degrade 4CB and for growth on 4CB as a sole source of carbon and energy. It was found by UV-scanning spectrophotometry that both strains of DJ-12 and DJ-26 degraded 4CB to produce the meta-cleavage compound and then to 4-chlorobenzoic acid (4CBA) through the meta-cleavage pathway without dechlorination step. The DJ-12 strain was also turned out to degrade 4CB to produce 4CBA as assayed by HPLC. Through conjugation with Pseudomonas putida KT2440, the genes responsible for degradation of 4CB in the strain DJ-12 were found to be associated with a plasmid of about 65kb in size.

Analysis for Torsion of Hollow Beam by Least Squares and Boundary Elements Method

김치경,배준태,Kim, Chi-Kyung,Bae, Joon-Tai Computational Structural Engineering Institute of 2012 한국전산구조공학회논문집 Vol.25 No.2

본 연구에서는 뒤틀림을 받고 있는 정사각형 단면의 중공단면 보를 최소자승법과 경계요소법을 이용하여 수치 해석하고 구조물을 해석하였다. 임계하중은 하중을 점차적으로 증가하여 구조물이 파괴가 발생하여 안정성을 상실하는 상태에서 가장 작은 하중을 의미한다. 뒤틀림을 받고 있는 beam은 일반 구조물에서 많이 발생하는 현상이며, 구조물의 안정성에 크게 영향을 미치고 있다. 최소자승법과 경계요소법은 복잡한 구조물에서도 물론, 다양한 경계조건을 포함하는 문제에 이르기까지 구조물의 안정성을 검사하는데 효과적인 수치해석 방법이다. 특히 뒤틀림의 문제에서는 단순성 및 일반성에 기인하여 매우 적합한 해석방법이다. 본 연구에서는 뒤틀림을 받고 있는 중공단면 보의 해석해를 유도하여 최소자승법으로 수치 해석하고 또한 경계요소법을 적용하여 빔의 안정성을 비교 검토하였다. 개발한 컴퓨터 프로그램의 타당성을 증명하기 위하여 삼각형, 사각형 그리고 타원형 단면에 대하여 각각 해석하여 해석해와 비교 검토하였다. In this paper we are concerned with the performance of structural stability of torsion in square cross section of a beam with holes. The critical load is defined as the smallest load at which the equilibrium of the structure fails to be stable as the load is slowly increased from zero. The beams subjected to torsion are frequently encountered in general structures and these forces influence to the stability of structure. The boundary element method is found to be very efficient and accurate for the analysis of torsion problems including complex boundary conditions with respect to its simplicity and generality. In this paper, it is required to derive the boundary element formulation for torsion problem and integrate directly on the discrete boundary. To investigate the validity of the developed computer program, three distinctly solid cross-sections which are elliptical, rectangular and triangular one are analyzed, and comparisons are made with analytical approaches where these can also be used.

오존에 의한 bacteriophage f2의 살균작용(殺菌作用)

김치경,Kim, Chi-Kyung 한국현미경학회 1981 Applied microscopy Vol.11 No.1

Bacteriophage f2 were treated with ozone at various concentrations for 20 minutes. The inactivation kinetics of f2 phage were examined during ozonation. In order to study the mode of action of ozone on the phage f2, absorption of the phage to the host pili was meassured by utilyzing radioactivity of tritium incorporated into the phage RNA. Sucrose density gradient analysis and electron microscopy were also used to prove the mechanism of ozone inactivation of the phage. Strucural proteins of the phage were broken by ozonation into many protein subunits. The extent of phage breakage was proportional to ozone concentration and reaction time. Percent decrease of the phage absorption to the host pili was coincident with the rate of ozone inactivation of the phage. Ozone inactivation of bacteriophage f2 was shown to be caused by the breakage of the structural protein and blockage of the phage absorption to the host pili.

Pseudomonas spp . 에 의한 4 - chlorobiphenyl 의 분해 및 Plasmid 와의 연관성

김치경,이익근 ( Chi Kyung Kim,Ik Keun Lee ) 생화학분자생물학회 1990 BMB Reports Vol.23 No.3

Including the Pseudomonas strains reported in the previous works, two bacterial strains which are able to degrade 4-chlorobiphenyl(4CB) were isolated from natural environments. They were investigated for their ability to degrade 4CB and for growth on 4CB as a sole source of carbon and energy. It was found by UV-scanning spectrophotometry that both strains of DJ-12 and DJ-26 degraded 4CB to produce the meta-cleavage compound and then to 4-chlorobenzoic acid (4CBA) through the meta-cleavage pathway without dechlorination step. The DJ-12 strain was also turned out to degrade 4CB to produce 4CBA as assayed by HPLC. Through conjugation with Pseudomonas putida KT2440, the genes responsible for degradation of 4CB in the strain DJ-12 were found to be associated with a plasmid of about 65kb in size.

하천수에서 Campylobacter jejuni 의 오염도와 그 생존율에 관한 연구

김치경,오학식,염곤,조민기 ( Chi Kyung Kim,Hak Shik Oh,Kon Ryeom,Min Ki Cho ) 한국하천호수학회 1986 생태와 환경 Vol.19 No.3·4

Campylobacter jejuni isolated from river and lake waters and chicken samples were examined for their contamination and survival in surface waters and for inactivation by chlorination. The isolation rates of C. jejuni from chicken samples were 50 to 100%, while only one out of 48 studies was positive from the surface water. When the organisms suspended in sterile river water were incubated at 4℃, they survived upto 20 days, but they died off after 1 day incubation at 30℃ or above. The in situ survival studies of C. jejuni in the waters of Dsecheong Dam and Han-river (1st bridge) revealed that they survived upto 14 days in winter, but for shorter period of time in spring and summer. The survival rates of the organism in the deeper water were a little longer than in the surface water, but the rates were not different between the both water environments. When the organisms were treated with 0. 5, 1. 0 and 2. 0 ㎎/ℓ chlorine solution at pH 7. 0 and 15℃ for 60 minutes, they were inactivated by about 1, 4, and 6 logs, respectively, The inactivation rate was increasingly affected by lowering the reaction pH and by increasing the reaction temperature.

흉부질환을 병발한 Von Recklinghausen's disease -2예 보고-

김치경,박재길,이홍균,Kim, Chi-Kyung,Park, Jae-gil,Lee, Hong-Kyun 대한흉부심장혈관외과학회 1980 Journal of Chest Surgery (J Chest Surg) Vol.13 No.2

Von Recklinghausen's disease is a systemic hereditary disorder with varied manifestations in bone, soft tissue, nervous system, and skin, the most common of which is the developement of multiple, small, cutaneous tumors with a characteristic histologic picture. Tumors develop after birth and before puberty in most cases, and they increase in number until old age. Malignant neoplasms that complicate multiple neurofibromatosis include gliomas of the optic nerve, astrocytomaas of the cerebral and cerebellar hemispheres, and sarcomas of peripheral nerves (femoral, tibial and intercostal nerves) and somatic soft tissues. Little attention has been paid to the presence of cystic lung disease in association with neurofibromatosis. Currently, most think of thoracic involvement in neurofibromatosis in terms of posterior mediastinal neuroma, pheochrocytoma, meningocele or, less commonly parenchymal pulmonary neurofibromas. Author have experienced 2 cases of Von Recklinghausen's disease. One case developed a hyge malignant Schwannoma in the parietal pleura of left 4th intercostal space and multiple benign neurofibromas (two in intercostal spacees and one in the neck) , and the other has several episodes of pneumothorax resulting from diffuse cystic lung disease which required closed thoracotomy drainage.

상실성빈맥의 수술치험 -1예 보고-

김치경,정진용,곽문섭,김세화,이홍균,홍순조,Kim, Chi-Kyung,Jeong, Jin-Yong,Kwack, Moon-Sup,Kim, Se-Wha,Lee, Hong-Kyun,Hong, Sun-Jo 대한흉부심장혈관외과학회 1988 Journal of Chest Surgery (J Chest Surg) Vol.21 No.6

Supraventricular tachyarrhythmias are readily characterized and understood, but the surgical procedures for their correction are complex and not easily mastered. Conversely, ventricular tachyarrhythmias are frequently difficult to characterize and localize electrophysiologically and their basic mechanisms are poorly understood. The role of the surgeon in the treatment of cardiac arrhythmia has changed dramatically during the past decade. This report is a case of 26 years old male with supraventricular tachyarrhythmia. The result of endocardial electrophysiologic study demonstrated accessory pathway connecting left atrium to left ventricle which located at left atrial free wall about 4 cm apart from the coronary sinus orifice. The accessory bundle interruption has been successfully accomplished utilizing the internal open heart technique. The operation consisted of dissection of the atrioventricular fat pad and division of all the superficial fibers going from the ventricle to the annulus. Following this, cryoablation made with cryoprobe at - 60$^\circ{C}$ for 90 seconds. The accessory pathway was successfully ablated without specific problems.

Caulobacter의 세포(細胞)의 형태(形態) 및 기능(機能)의 분화(分化)에 대한 염소 및 염소화합물의 영향(影響)

김치경,박문국,염곤,Kim, Chi-Kyung,Park, Moon-Kook,Yum, Kon 한국현미경학회 1982 Applied microscopy Vol.12 No.1

Caulubacter is distinctive in the morphology and replication and ubiquitous in the biosphere, especially in every type of aquatic environment. In water and waste-water treatment processes, chlorine and chlorine compounds have been used as a main disinfectant throughout the world. Therefore, Caulobacter in the waters should be affected by chlorination of the waters. The objective of this study is to determine the effects of the disinfectants on Caulobacter cells and on the developmental processes of the cells. The Caulobacter swarmer cells were disinfected by chlorine at pH 7.0 minutes of the reaction with 2.0 mg/l of infected at pH 10.0. The swarmer cells treated with 2.0 or 4.0 mg/l of chlorine for 15 minutes lost their flagella and were observed by electron microscopy to be damaged on their cell surfaces, discharging some cellular materials. When the chlorinated swarmers and untreated control samples were recultivated in fresh PYE broth medium, the control swarmers multiplicated exponentially after one-hour lag phase, whereas the chlorinated swarmers extended the lag phase to about four hours. During the extended lag phase, the cells were proved by electron microscopy to be grown and be in predivisional step, but no swarmer cell was found. When the stalked cells were chlorinated, almost all the cells were observed to have their stalks broken and some cellular materials discharged. In those samples recultivated, many cells differentiated to possess an abnormally elongated stalk with several crossbands on it. This suggests that the chlorine-shocked Caulobacter cells can develope to abnormal morphology in water environments which they can survive and regrow in.