• 대한골관절종양학회지
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• 제11권2호
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• pp.118-125
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• 2005

목적: 골육종에서 세포 사멸과 관련된 survivin, bcl-2, bax 유전자의 발현을 조사하여 임상적 결과와의 연관성에 대해 알아 보고자 하였다. 대상 및 방법: 항암 약물 치료 전 절개 생검으로 얻은 50예의 골육종 조직을 면역조직화학 염색법을 통하여 survivin, bcl-2, bax의 발현을 관찰하였다. 임상적으로 항암 약물 치료에 대한 반응율, 국소재발, 원격전이, 종양학적 결과 등을 연구하여 surviving, bcl-2, bax 유전자 각각의 발현 또는 이들의 복합적인 발현과의 연관성에 대해 통계적으로 분석하였다. 결과: 면역조직화학염색법으로 검사한 survivin 유전자의 발현은 26예(52%)에서 관찰되었고, bcl-2는 23예 (46%), bax는 21예 (42%)에서 관찰되었다. Survivin과 bcl-2의 공동발현은 19예(38%), survivin과 bax의 공동 발현은 13예(26%), bcl-2와 bax의 공동 발현은 8예 (16%), 그리고 이들 3가지 모두의 발현은 총 8예 (16%)에서 관찰되었다. 검사한 3가지 세포 사멸 관련 유전자의 발현과 여러 임상적 변수와의 상관 관계를 조사 하였을 때 조직학적 분류, 나이, 성별, 국소 재발 등과는 유의한 연관성이 없었다. 항암 약물 반응율과 통계적으로 유의한 연관성을 보인 인자는 bcl-2 (P=0.04), 그리고 survivin과 bcl-2가 동시 발현된 경우 (P=0.044)였으며 나쁜 항암 약물 반응율을 나타냈다. 종양학적 결과 중 질병으로 인한 사망과의 연관성을 보인 인자 역시 bcl-2 (P=0.001), 그리고 survivin과 bcl-2가 동시발현된 경우 (P=0.027)였으며, 이들의 발현은 나쁜 종양학적 결과를 나타냈다. Kaplan-Meier 생존율 분석에서 bcl-2 (P=0.0012)의 발현과 survivin, bcl-2의 동시 발현 (P=0.0075)은 생존율과 역의 상관관계를 보였다. 결론: 골육종에서 세포 사멸 관련 유전자의 발현은 비교적 높게 보였으며, bcl-2의 발현은 항암 약물치료에 대한 불량한 반응과 낮은 생존율에 의미 있는 연관성을 보이며, survivin은 bcl-2와 동시에 발현되는 경우에만 이러한 종양학적 결과와 의미 있는 관련이 있었다. 따라서 세포 사멸 관련 유전자들의 면역조직화학염색법을 통한 관찰이 골육종의 예후 판정에 도움이 될 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제17권12호
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• pp.1909-1921
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• 2007

Significant progress has recently been made concerning the engineering of deoxysugar biosynthesis. The biosynthetic gene clusters of several deoxysugars from various polyketides and aminoglycosides-producing microorganisms have been cloned and studied. This review introduces the biosynthetic pathways of several deoxysugars and the generation of novel hybrid macrolide antibiotics via the coexpression of deoxysugar biosynthetic gene cassettes and the substrate-flexible glycosyltransferases in a host organism as well as the production of TDP-deoxysugar derivatives via one-pot enzymatic reactions with the identified enzymes. These recent developments in the engineering of deoxysugars biosynthesis may pave the way to create novel secondary metabolites with potential biological activities.

• KSBB Journal
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• 제16권1호
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• pp.1-10
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• 2001

Escherichia coli has been used as an expression work horse for foreign genes. This article summarized recent development in genetic engineering techniques for overproduction of medical proteins and industrial enzymes. Special emphasis was placed upon research activities concerning folding and refolding of inclusion bodies at genetic and fermentation levels. Plasmid and mRNA stabilization, development of strong inducible promoters, modification of translational elements and reduction of rpoteolytic degradation were carried out to elevate an expression level of a target protein. Optimization of culture conditions, improvement of denaturation and renaturation steps and coexpression of molecular chaperones or foldase were accomplished to produce active proteins in soluble form. Fusion protein systems with selective separation and surface display technology were also performed in an effort to make the E. coli expression system more effective and versatile.

• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1353-1356
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• 2008

RNase E (Rne) plays a major role in the decay and processing of numerous RNAs in E. coli, and protein inhibitors of RNase E, RraA and RraB, have recently been discovered. Here, we report that coexpression of RraA or RraB reduces the ribonucleolytic activity in rne-deleted E. coli cells overproducing RNase ES, a Streptomyces coelicolor functional ortholog of RNase E, and consequently rescues these cells from growth arrest. These findings suggest that the regulators of ribonuclease activity have a conserved intrinsic property that effectively acts on an RNase E-like enzyme found in a distantly related bacterial species.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.188-188
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• 2001

Human cytochrome B5 (CYB5) was coexpressed with cytochrome P450 1A2 (CYP1A2), NADPH-CYP450 reductase (CYPR) and Ν-acetyltransferase 2 (NAT2) in Chinese hamster ovary (CHO) cells. The expression of four proteins was determined by Western blot analyses. The introduction of cDNAs to CHO cells were transduced via retroviral vectors. The cytotoxicity assay of 2-aminoanthracene (2-AA) and aflatoxin B$_1$were approximately 4-fold more sensitive than CYB5 free cells.(omitted)

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (1)
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• pp.739-742
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• 2002

This paper addresses a new statistical method, IFSAcycle, which is an unsupervised learning method of analyzing cell cycle-related gene expression data. The IFSAcycle is based on the independent feature subspace analysis (IFAS) [3], which generalizes the independent component analysis (ICA). Experimental results show the usefulness of IFAS: (1) the ability of assigning genes to multiple coexpression pattern groups; (2) the capability of clustering key genes that determine each critical point of cell cycle.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.6081-6084
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• 2013

Objective: Both estrogen receptors, ER alpha ($ER{\alpha}$) and ER beta ($ER{\beta}$), are expressed in 50-70% of breast cancer cases. The role of $ER{\alpha}$ as a prognostic marker in breast cancer has been well established as its expression is negative correlated with tumor size and lymph node metastasis. $ER{\beta}$ is also a favorable prognostic predictor although this is less well documented than for $ER{\alpha}$. Materials and Methods: To explore whether ERs independently or together might influence clinical outcome in breast cancer, the correlation between the ERs with the clinicopathological features was analyzed in 84 patients. Results: $ER{\alpha}$ expression negatively correlated with tumor stage (r=-0.246, p=0.028) and tended to be negatively correlated with lymph node status (r=-0.156, p=0.168) and tumor size (r=-0.246, p=0.099). Also, $ER{\beta}$ was negatively correlated with nodal status (r=-0.243, p=0.028), as was coexpression of $ER{\alpha}$ and $ER{\beta}$ (p=0.043, OR=0.194, 95% CI= 0.040-0.953). Conclusion: Coexpression of ERs might serve as an indicator of good prognosis in breast cancer patients.

• Journal of Microbiology and Biotechnology
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• 제11권4호
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• pp.685-692
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• 2001

A gene, Egl, from Paenibacillus sp. KCTC 8848P encoding endo-${\circ}$-1,4-glucanase was cloned and expressed in Escherichia coli. It consisted of an open reading frame of 1,191 bp for a protein that consisted of 397 amino acids with a molecular weight of 44,539 Da. The deduced amino acid sequence of the endo-${\circ}$-1,4-glucanase gene had a 94% similarity to the endo-$\beta$-1,4-glucanase of Bacillus polymyxa. The Egl gene was also expressed in Saccharomyces cerevisiae secreting Endomyces fibuliger $\beta$-glucosidase (BGL1) under the control of the alcohol dehydrogenase (ADC1) gene promoter, S. cerevisiae transformant producing both endo-${\circ}$-1,4-glucanase and ${\circ}$-glucosidase grew on carboxymethyl cellulose as the sole carbon source.

• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2034-2042
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• 2015

A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25℃ for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'-triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.228-233
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• 2008

Effects of chaperones on mRNA stability and gene expression were studied in order to develop an efficient Escherichia coli expression system that can maximize gene expression. The stability of mRNA was modulated by introducing various secondary structures at the 5'-end of mRNA. Four vector systems providing different 5'-end structures were constructed, and genes encoding GFPuv and endoxylanase were cloned into the four vector systems. Primer extension assay revealed different mRNA half-lives depending on the 5'-end secondary structures of mRNA. In addition to the stem-loop structure at the 5'-end of mRNA, coexpression of dnaK-dnaJ-grpE or groEL-groES, representative heat-shock genes in E. coli, increased the mRNA stability and the level of gene expression further, even though the degree of stabilization was varied. Our work suggests that some of the heat-shock proteins can function as mRNA stabilizers as well s protein chaperones.