• The Microorganisms and Industry
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• v.16 no.3
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• pp.44-47
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• 1990

Avery, MacLeod, McCarty가 1944년에 세균에서 유전적 재조합이 이루어진다는 사실을 발견한 후 세균은 진화 학자들과 미생물 학자들로 부터 주목을 받기 시작했다. 왜냐하면 세균은 자연생태계에서 또다른 형태의 유전적 적응성을 지니고 그러한 돌영변이 중 일부는 모세포(parent cell)보다도 주변환경에 더 잘 적응되었기 때문이다. 이제까지 GEM들이 생태계에서 유전자들 전이시키는 빈도가 대부분 낮았고, 토양이나 다른 자연생태계애서 유전자의 전이가 지속적으로 일어난다는 실험적 증거는 없었지만 이들을 생태계에 방출한 결과 유전자 전이가 몇몇 실험에서 확인된 적이 있어 토양에서의 유전적 전이의 가능성을 강하게 암시하고 있다. 하지만 어떻게 전이되고 토양의 물리, 화학및 전이에 필요한 최소한의 donor와 recipient의 수와 정확한 감지 방법등이 아직까지 밝혀져 있지 않은 상태이다. 더우기 토양환경에서 미생물의 활성과 생태, 군집 동태에 영향을 줄 수 있는 기능을 나타내려면 얼마만큼의 재조합 세균이 단위면적당 필요한지도 밝혀지지 않은 상태이다. 따라서 이러한 여러가지 문제점을 밝히는 것은 학문적인면 뿐만 아니라 진화론적인 이론에도 도움이 되며 GEM들이 토양이나 다른 생태계에 유출되었을 때의 환경영향평가나 규제를 하는데에도 도움이 될 수 있다고 본다.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.95-98
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• 2013

Following construction of expression vectors in Escherichia coli, a new procedure involving two-step column purifications with a Fast Performance Liquid Chromatography System was developed for purification of the oxygenase component of alkylphenol hydroxylase of Pseudomonas alkylphenolia. From 50 g wet cake of recombinant E. coli BL21(DE3)(pJJPMO2) cells, 110 mg of pure protein in a heterodimeric form containing a stoichiometric amount of iron were obtained and it exhibited a specific activity of 147 nmole/min/mg.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.291-294
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• 2006

기존의 DRM 보호기법은 특정 콘텐츠 포맷에 일부 제한적인 보호방식의 특성이 있기 때문에 현재 모든 디지털 콘텐츠에 대해서 범용적으로 DRM 보호기법을 적용할 수 없는 문제점이 있으므로, 아직도 많은 종류의 디지털 콘텐츠는 DRM 보호기능을 제공받지 못하고 있다. 또한, 기존의 DRM 보호기법은 암호화 알고리즘을 기반으로 많은 양의 데이터에 대해서 암/복호화를 수행하기 때문에 속도가 많이 소요되는 단점이 있다. 본 논문에서는 범용적인 DRM 보호를 위해 콘텐츠 헤더의 부분 암호화 방식과 분할된 콘텐츠에 대한 순열 재조합을 이용한 방법으로 모든 디지털 콘텐츠에 대해서 범용적으로 DRM 보호기능을 제공하는 기법을 제안하였다. 또한 이 기법은 콘텐츠의 암/복호화 수행 속도를 향상 시키고 동시에 기존의 보안성은 유지하는 기능을 포함하고 있으므로 다양한 형식의 디지털 콘텐츠에 대하여 유연하게 적용이 가능하며, 다양한 비즈니스 환경에 확장성 있는 통합 가능하다.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06b
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• pp.508-513
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• 2010

본 논문에서는 정칙 이진 행렬을 이용하여 유전 알고리즘의 성능을 개선할 수 있는 메타 유전 알고리즘을 설계한다. 정칙 이진 행렬은 유전 알고리즘에서 사용되는 이진 인코딩에서의 기저 변환에 중요하게 쓰일 수 있다. 이 논문에서는 정칙 이진 행렬의 기저 변화를 위한 아이디어와 더불어 정칙 이진 행렬의 표현과 재조합 연산에 대한 아이디어를 제시했던 연구들을 소개하고, 메타 유전 알고리즘을 위한 변이와 초기 해집단 생성, 평가에 대한 방법론을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.989-992
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• 2010

리팩토링은 시스템의 기능 변경 없이 코드 구조를 재조정하여 가독성을 높이고 유지보수성을 향상하기 위함이다. 기존의 어스팩트 리팩토링은 프로그램의 특정 부분을 어스팩트로 정의하여 리팩토링하거나 구현된 어스팩트 명세를 재구성하는 방식으로, 객체지향 프로그램에 적용하는데 어려움이 있다. 본 논문은 객체지향 리팩토링에 어스팩트 개념을 적용하기 위한 구체화된 접근방법을 제시하는 것이 목적이며 이를 위해 프로그램 의존성 그래프를 이용한다. 리팩토링의 주요 어스팩트인 중복 코드는 프로그램 의존 그래프에서 노드 사이의 순서관계를 비교하여, 리팩토링을 위한 어스팩트 후보로 변환하며 이를 근거로 재조합 함으로써 캡슐화된 객체 내부의 리팩토링 요소를 편리하게 처리할 수 있다.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.295-300
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• 1989

Screening of Pseudomonas strains that can be used as hosts for expression of crystal protein gene of Bacillus thuringiensis subsp. kurstaki HD-73 was carried out. From rhizosphere soil of 7 kinds or crops as fluorescent Pseudomonas strains were isolated. A hybrie plasmid, pKTC1, composed of the broad host range vector pKT230 and the crystal protein gene was constructed and used for transformation of the 35 Pseudomonas strains. As the result, the crystal protein gene could be introduced into 4 isolates. Several methods including bioassay and immunochemical detection indicated that the crystall protein gene was expressed in the Pseudomonus isolates.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.306-311
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• 2005

In this study, the amino-terminal half truncated lump and the whole lump genes from Photobacterium phosphoreum coding for the lumazine protein were cloned by polymerase chain reaction and expressed in Escherichia coli. To identifiy of the binding site of the ligand or substrate, the amino acid identities from the sequences of the lumazine protein, yellow fluorescent protein, and riboflavin synthase from different organisms were also compared and analyzed.

• KSBB Journal
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• v.23 no.3
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• pp.205-212
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• 2008

The efficient soluble expression of human epidermal growth factor (hEGF) was achieved by using functional fusion partners in cytoplasm and periplasm of Escherichia coli (E. coli). hEGF was over-expressed in inactive inclusion body form in cytoplasm of E. coli due to improper disulfide bond formation and hydrophobic interaction, yielding about 5.9 mg/L in flask culture. Six functional fusion partners were introduced by linking to N-terminal part of hEGF gene for the high-level expression of soluble and active hEGF in cytoplasm and peri plasm region. Three fusion partners for cytoplasmic expression such as acidic tail of synuclein (ATS), thioredoxin (Trx) and lipase, and three fusion partners for periplasmic expression such as periplasmic cystein oxidoreductases (DsbA and DsbC) and maltose binding protein (MBP) were investigated. hEGF fused with ATS and DsbA showed over 90% of solubility in cytoplasm and periplasm, respectively. Especially DsbA was found to be an efficient fusion partner for soluble and high-level expression of hEGF, yielding about 18.1 mg/L and three-fold higher level compared to that of insoluble non-fusion hEGF in cytoplasm. Thus, heterologous proteins containing complex disulfide bond and many hydrophobic amino acids can effectively be produced as an active form in E. coli by introducing a suitable peptide or protein.

• Analytical Science and Technology
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• v.25 no.6
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• pp.483-491
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• 2012

This study is to investigate the issues on how to secure stability during the purification process for the production of recombinant protein A. The final recombinant protein A is produced by passing through the cation exchange column (SP) and the anion-exchange column (Q) during the production process, for which the samples produced by the step-by-step processes can be exposed to trouble in securing stable storage in case the next process cannot be taken within the proper time period. Accordingly, this study aims to evaluate the proper storage conditions and length of time when storing samples produced in the production process. That is, in this study, how to store fair samples, how long the storage period should be set up, and how to evaluate the security of its quality depending on time are dealt with. The items to be experimented with were enodotoxin, SDS-PAGE, HPLC purity and concentration. Experimental results showed that after passing the cation exchange column, when stored at $4^{\circ}C$ or room temperature, SDS-PAGE showed a major band, endotoxin is 5.0 Eu/mg or less, and concentration is on average of 8.21 to 8.24 mg/mL and RSD% 0.10~0.62%. In addition, HLPC purity showed somewhat stable results; at the HPLC purity 214 nm, the average is 99.24% to 99.37% and RSD% is 0.22~0.29%, while the average is 89.72% to 89.80% and RSD% 0.62~1.26% at 280 nm. On the contrary, after passing the anion exchange column, when stored at $4^{\circ}C$ or room temperature, SDS-PAGE revealed the major band, endotoxin is 0.5 Eu/mg or less, and concentration is on average of 5.59 mg/mL and RSD% 0.03~0.10%. when it comes to HLPC purity, the result showed that at the HPLC purity 214 nm, the average is 99.74% and RSD% is 0.10~0.11%, while the average is 96.16% to 96.85% and RSD% 0.72~1.13%. In conclusion, the stability of fair samples of recombinant protein A during the manufacturing process could be obtained without substance decomposition for 7~8 days at $4^{\circ}C$ or 20~21 days at room temperature.

• Journal of Life Science
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• v.21 no.8
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• pp.1149-1155
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• 2011

Myostatin (MSTN) belongs to the transforming growth factor-${\beta}$ superfamily or growth and differentiation factor 8 (GDF-8), and functions as a negative regulator of skeletal muscle development and growth. Previous studies in mammals have suggested that myostatin knock-out increased muscle mass and decreased fat content compared to those of the wide type. Recently, several studies on myostatin have beenconducted on the block myostatin signal pathway with myostatin antagonists and the MSTN regulation with RNAi to control myostatin function. This study was performed to analyze growth and muscle alteration of Oncorhychus masou by treatment with recombinant myostatin prodomains derived from fish. We designed myostatin prodomains derived from P. olivaceus (pMALc2x-poMSTNpro) and S. schlegeli (pMALc2x-sMSTNpro) in a pMALc2x expression vector, and then purified the recombinant proteins using affinity chromatography. The purified recombinant proteins were treated in O. masou through an immersion method. Recombinant protein treated groups did not show a significant difference in weight, protein, or lipid composition compared to the control. However, there was a difference in the average number and area for histological analyses in the muscle fiber. At twelve and twenty-two weeks from the initial treatment, there were differences in averagefiber number and area between the 0.05 mg/l treated-group and the control, but the numbers were similar to those of the control during the same time period. At twelve weeks, however, 0.2 mg/l treated-group had an increase in average fiber number and decrease in average fiber area compared to the control. At twenty-two weeks, the pMALc2x-sMSTNpro 0.2 mg/l treated-group was induced and showed a decrease in average fiber number and increase in average fiber area. The results between twelve and twenty-two weeks showed that the fiber numbers had decreased, whereas average fiberarea had increased due to sMSTNpro. It is understood that the sMSTNpro induced only hyperplasia at twelve weeks, after which it induced hypertrophy. Recombinant myostatin prodomains derived from fish may induce hyperplasia and hypertrophy in O. masou depending upon the time that has elapsed.