산소유리기의 뇌 손상작용에 대한 NMDA 수용체 길항제(MK-801)의 방어효과 : CO중독 흰쥐에 대한 고압산소 치료 과정에서 In the Hyperbaric Oxygen Treatment of CO Poisoned Rat

정대은,류승호,조진아,박항배,송재철 大韓産業醫學會 1997 대한직업환경의학회지 Vol.9 No.1

The effects of NMDA-receptor antagonist(MK-801) were assessed for the oxygen free radical mediated brain(hippocampus) injury with eights rats which were exposed to carbon monoxide(CO) followed by hyperbaric oxygen(HBO) treatment. Superoxide dismutase(SOD) and malondialdehyde(MDA) were used as parameters of the oxygen free radical reaction. Experimental groups consisted of (1) control group(=breathing with air), (2) Co group(=exposed to CO after air breath), (3) CO-air group(exposed to CO after air breath followed by air breath), and (4) CO-HBO group(=exposed to CO after air breath followed by 3 ATA HBO). Each group was divided two subgroup according to the pretreatment(normal saline of MK-801). CO, CO-air and HBO groups increased in SOD activity as compared with control group. And CO-air and HBO groups increased in MDA as compared with control and CO group. Pretreatment of MK-801 decreased SOD activities significantly(p-value<.05), but MDA amount not significantly(p-value=.107). These results suggest a useful protective effect of NMDA-receptor antagonist(MK-801) in CO induced hippocampal injury mediated by oxygen free radicals.

메타게놈 서열에 존재하는 보존적인 전사와 번역 인자를 이용한 ORF 예측

정대은(Dea-Eun Cheong),김근중(Geun-Joong Kim) 한국생물공학회 2010 KSBB Journal Vol.25 No.5

미생물은 지구상에 약 5 × 10<SUP>30</SUP> 정도의 개체가 존재하며, 350~550 Pg (1Pg = 10<SUP>15</SUP>g)의 탄소, 85~130 Pg의 질소, 9~14 Pg의 인 등, 지구상의 어떠한 생물 종보다 거대한 양의 원소를 포함하고 있다 [28]. 또한 이러한 미생물과 생태계를 구성하는 다른 유기체나 무기물과의 관계가 지속적으로 밝혀지고 있다. 이러한 연구들의 기본적인 목표는 상호작용에 중요한 인자들의 규명 (대표적으로 유전자)하는 것이기 때문에, 염색체에 존재하는 true ORF의 검색과 확인은 가장 중요한 기본 수단이 된다. 그러나 다양한 미생물로 구성된 환경 유전체는 기존 정보로 검색 가능한 비율을 정확하게 유추할 수 없기에 많은 어려움이 있다. 이렇게 경계가 불분명한 자료의 검색을 위해서는 보다 많은 정보를 필요 (training 이나 space를 규정하기 위한 보다 많은 유전자 서열)로 하며, 다른 검색 방법이나 기법들이 추가적으로 개발되어야 할 것이다. 이러한 방법의 대안으로써, 미생물의 유전자간 서열에 존재하는 전사/번역인자의 보존성에 근거한 검색방법은 개량여하에 따라 광범위한 적용 범위를 지닐 것이다. 현 수준에 서도 조합 탐색, 즉 기존의 방법과 혼용하거나 기존의 방법을 보완하는 과정으로 충분한 가치를 지니고 있다. 이러한 추정은, 기존의 ORF 중심의 발굴 결과와 전혀 일치되지 않는 경우에서부터 90% 이상 일치하는 등의 결과로서 확인하였다. 일치 되지 않는 많은 경우가 BLASTing으로 검색되지 않는 새로운 ORF를 포함하기 때문이다. As sequencing technologies are steadily improving, massive sequence data have been accumulated in public databases. Thereby, programs based on various algorithms are developed to mine useful information, such as genes, operons and regulatory factors,from these sequences. However, despite its usefulness in a wide range of applications, comprehensive analyses of metagenome using these programs have some drawbacks, thereby yielding inaccurate or complex results. We here provide a possibility of signature sequences (cis-acting transcriptional and translational factors of metagenome) as a hallmark of ORFs finding from metagenome.

유전자 표적화를 위한 단백질공학 연구동향

정대은(Dea-Eun Cheong),김근중(Geun-Joong Kim) 한국생물공학회 2010 KSBB Journal Vol.25 No.3

Monogenic disease의 치료를 위한 하나의 전략으로 viral vector를 이용한 gene therapy에 비해 독성이 적은 gene targeting 기술을 이용하기 위한 연구가 진행되고 있다. 이러한 구의 주된 관점은 자연적인 HR의 낮은 효율을 개선하기 위한 DSB 유도 방법으로, 선택성을 높일 수 있는 긴 염기서열의 인식이 가능한 artificial endonuclease의 개발이다. 본 글에서는 이러한 artificial endonuclease 중, 가장 많이 연구 되고 있는 homing endonuclease와 zinc finger nuclease를 간략히 소개하였다. 전자와 후자 모두, 인식 서열에 대한 일정 수준의 tolerance (인식 서열 일부가 특이적이지 않아 다른 염기로 구성된 경우)가 존재하여, 일정한 비율로 다른 target을 절단할 수 있는 가능성이 존재한다. 이러한 점은, meganucleases를 치료 목적으로 이용할 때 세포 독성을 나타내는 근본원인 중 하나이다. 두 종 모두 이러한 특성을 가짐에도 불구하고, 완전한 비자연적인 후자 보다는 전자의 경우가 보다 효과적이며 낮은 세포독성을 보이는 것으로 보고되고 있다. 물론 실험 조건이나 적용되는 세포 종류, 인위적인 단백질의 발현 정도에 따라 세포 독성 유무 또는 정도에 차이가 나타남이 확인되고 있다. 이러한 사실들에 근거할 때, gene targeting을 유도하기 위한 artificial endonuclease의 서열 특이성을 증대시키는 것이 가장 중요하나, 그 외 여러 인자들에 대한 복합적인 연구 역시 필요함을 보여준다. 현재까지 실제 치료제로 쓰인 예는 없지만, 시험관내에서 보이는 결과와 모델 개체에서 이루어진 표적화 정도, 관련된 단백질 치료제들이 지닌 잠재성을 비교할 때 매우 큰 가능성을 지니고 있음은 충분히 확인할 수 있다. Monogenic diseases are resulted from modifications in a single gene of human cells. Because their treatment with pharmacological medicine have a temporary effect, continuous nursing care and retreatment are required. Gene therapy, gene targeting and induced pluripotent stem cell (iPSC) are considered permanent treatment methods of them. In gene therapy, however, retroviral vectors that have potential toxicity caused by random insertion of harmful virus are used as vehicles for transferring genetic materials. On the other hand, gene targeting could replace and remove the modified gene though homologous recombination (HR) induced by site-specific endonucleases. This short review provides a brief overview on the recently tailored endonucleses with high selectivity for HR.

항시발현 프로모터를 이용한 대장균에서의 β-glucosidase 가용성 발현증진

정대은(Dae-Eun Cheong),유수경(Su-Kyoung Yoo),최혜지(Hye-Ji Choi),김근중(Geun-Joong Kim) 한국생물공학회 2021 KSBB Journal Vol.36 No.2

Sinorhizobium meliloti β-glucosidase (β-D-glucoside glucohydrolase: EC 3.2.1.21) is an exocellulase and cleavages β-(1-4) glycosidic bonds in poly- and oligosaccharides. It has also high activity toward indican, a precursor to indigo and indirubin used as clothing dyes, cosmetics and antimicrobial agents. Typically, this enzyme induced with IPTG under the control of the corresponding promoter was mainly produced as non-functional aggregates in Escherichia coli XL1-Blue and BL21 (DE3). In this study, expression vectors with a mined constitutive promoter (CEM) from metagenome were employed to increase the soluble expression of S. meliloti β-glucosidase. The resulting efficiency of constitutive expression systems was compared with those of the commonly used inducible systems in terms of the specific activity and solubility ratio. Consequently, recombinant β-glucosidases were mainly expressed in soluble form (82-97%) by the constitutive promoter CEM and thus showed the highest specific activity in the recombinant E. coli XL1-Blue harboring pCEMT.

Differential antimicrobial activity of Artemisia mongolia Fischer extract against pathogenic bacteria and Lactobacillus spp.

D. E. Cheong(정대은),H. S. Jung(정현수),M. K. Cha(차민경),J. S. So(소재성) 한국생물공학회 2004 한국생물공학회 학술대회 Vol.2004 No.10

암모니아 산화 고균 선택적 항체탐침자 개발

추연진,정대은,김근중 한국생물공학회 2022 KSBB Journal Vol.37 No.2

Ammonia oxidation is the first step of nitrification and plays an important role in global nitrogen cycle. Over the past 20 years, it has been founded that archaeal amoA gene is more abundant than bacterial amoA gene in diverse habitats. However, most of ammonia-oxidizing archaea (AOA) discovered by molecular techniques so far have not been cultivated yet in pure state. Thus, alternative methods of probing AOA are urgently needed. In this study, we attempted to produce antibody probes that specifically bound to a marine AOA strain, by generating polyclonal antibody using a subunit of specific ammonia monooxygenase (AMO) for ammonia oxidation. The resulting antibody could be used for detection of the AOA strain as illustrated by immunofluorescence staining in this work. Our results thus indicate that the typically generated polyclonal antibody would have broad invitro and in-situ applications in environmental microbiology and biotechnology.

재조합 단백질의 기능적 발현에 필요한 expression module의 통합적 조율

박소연,정대은,김근중,Park, So-Yeon,Jeong, Dae-Eun,Kim, Geun-Jung 한국미생물학회 2009 微生物과 産業 Vol.35 No.2

대유행이 예상된 시기의 렙토스피라 감염력에 대한 연구-한 특수집단을 대상으로-

최보율,정대은 외5명 한국역학회 1992 Epidemiology and Health Vol.14 No.1

비 확공성 골수강내 교합정을 이용한 경골 간부 골절의 치료

전호승,윤형구,전광표,정대은,박만제 대한골절학회 1996 대한골절학회지 Vol.9 No.2

Recently intramedullary nailing has become the most common method treating tibial fractures. Reamed intramedullary nailing technique leaves the problem of destroying thc endosteal blood supply, which associated with delayed union and postoperative infection. Recent reports have shown excellent rate of union and low rate of infection with unreamed interlocking intramedullary nail. Author reviewed 58 cases of tibia shall fractures that were treated with unreamed interlocking nail from Feb. 1992 to Feb. 1994. I. Forty nine fractures were closed and 9 were open (Gustilo-Andersonl;3,II;5, IIIa;1). Thirty one fractures involved the distal portion, 19 fractures the middle portion, 6 fractures the proximal portion and 2 fractures were segmental. 2. Thirty six cases were male and 22 were female. The most common age was 3rd decade (25.8%). 3. The most common cause was traffic accident. 4. Average interval from injury to operation were 5.7 days in closed fracture and 11.3 days in open fracture. 5. The mean duration of hone union were 15.7 weeks in closed fracture and 19.5 weeks in open fracture. 6. Complications include I case of delayed union, I case of joint stifmess and 1 case of screw failure. 7. According to the functional results by Klemm and Borner, 42 cases were excellent, 15 cases were good and 1 was fair.

Ender 정을 이용한 경골골절의 치료 : Ender 정 삽입술시 기술적 측면에 대한 고찰 Technical Considerative of Ender Nailing on Tibial Fracture

전호승,윤형구,전광표,정대은,장대영 대한골절학회 1995 대한골절학회지 Vol.8 No.2

Fractures of the tibia are one of the most common injury encountered by orthopaedic surgeons and their treatments are considered to be difficult due to serious complications. Many treatment modalities were introduced. Among them, Ender nailing is considered one of the useful modality because it is a relatively simple and, less invasive procedure. Authors analized l23 tibial fractures treated with Endr nails from Feb. 1986 to Feb. 1992 to solve the problems during Ender nailing. The follow up ranged from 12months to 57 months with an average of 17 months. The results are as follows; l. Among 123 patients, 93 cases are male and 30 cases are female. Traffic accident is the most common cause of injury. 2. Average interval from injury to operation is 9 days and average 2.7 Ender nails are used. The mean duration of the bone union is 19.1 weeks. 3. To prevent knee joint pain, more distal medial and lateral portal of entry and more posteriorly located lateral portal of entry were used. 4. To provide stability of distal 1/3 fracture, 3 or more nails are introduced with fanning in AP and lateral plane. 5. to provide stability of the comminuted fractures, convexities of at least 2 nails are located at the comminuted site. 6. To prevent rotation of the middle fragments of segmental fractures, technique of temporary Steinmann pin fixation for handling the middle fragment during operation were used.