• Parasites, Hosts and Diseases
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• 제39권4호
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• pp.313-318
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• 2001

The identification , characterization and quantification of Plasmodium sp. genetic polymorphism are becoming increasingly important in the vaccine development. We investigated polymorphism of Plasmodium vivax GAM-1 (PvGAM-1) gene in 30 Korean isolates. The polymorphic region of the PvGAM-1 gene, corresponding to nt 3792-4029, was amplified using polymerase chain reaction (PCR) followed by sequencing. All of the P. viuax Korean isolates were one type of GAM-1 gene, which were identical to that of the Belem strain. It is suggested that PvGAM-1 could not be used as a genetic marker for identifying or classifying P. vivax Korean isolates. It revealed that the polymorphic pattern as acquired basically by duplication and modification or deletion event of a 33 bp-motif fragment ended by poly guanine (G) and that there were at least three complete and one partial 33 Up-motif sequences within the polymorphic region in the longest cases such as those of South Korean and Belem isolates. In addition, we clustered P. vivax isolates with parsimonious criteria on the basis of PvGAM- 1 polymorphic patterns (insertion/deletion patterns) .

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1683-1690
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• 2013

The cyclic AMP receptor protein (CRP) homolog, GlxR, controls the expression of several genes involved in the regulation of diverse physiological processes in Corynebacterium glutamicum. In silico analysis has revealed the presence of glxR binding sites upstream of genes ptsG, adhA, and ald, encoding glucose-specific phosphotransferase system protein, alcohol dehydrogenase (ADH), and acetaldehyde dehydrogenase (ALDH), respectively. However, the involvement of the GlxR-cAMP complex on the expression of these genes has been explored only in vitro. In this study, the expressions of ptsG, adhA, and ald were analyzed in detail using an adenylate cyclase gene (cyaB) deletion mutant and glxR deletion mutant. The specific activities of ADH and ALDH were increased in both the mutants in glucose and glucose plus ethanol media, in contrast to the wild type. In accordance, the promoter activities of adhA and ald were derepressed in the cyaB mutant, indicating that glxR acts as a repressor of adhA. Similarly, both the mutants exhibited derepression of ptsG regardless of the carbon source. These results confirm the involvement of GlxR on the expression of important carbon metabolic genes; adhA, ald, and ptsG.

• ALGAE
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• 제24권2호
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• pp.85-91
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• 2009

The filamentous cyanobacterium Anabaena sp. Strain PCC 7120 produces a developmental patten of single hete- rocysts separated by approximately 10 vegetative cells. Heterocysts differentiate from vegetative cells and are spe- cialized for nitrogen fixation. The patS gene, which encodes a small peptide that inhibits heterocyst differentiation, is expressed in proheterocysts and plays a critical role in establishing the heterocyst pattem. Another key regulator of heterocyst development is the hetR gene. hetR mutants fail to produce heterocysts and extra copies of hetR on a plas- mid cause a multiple contiguous heterocyst phenotype. To elucidate the relationship between these two counter act- ing factors in the genetic regulatory pathway during heterocyst differentiation, the expression patterns of a patS-gfp and a hetR-gfp fusion were examined in a patS deletion and a hetR deletion strain. The results, in combination with the result from a hetR and patS double deletion strain, suggest patS and hetR are mutually antagonistic and the bal- ance between these two factors in tow different cell types (heterocysts and vegetative cells) may be critical during the decision making process on their cell fates.

• Environmental Analysis Health and Toxicology
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• 제14권1_2호
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• pp.1-12
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• 1999

Recently, several new methods for the detection of genetic damages in vitro and in vivo based on molecular biological techniques were introduced according to the rapid progress in toxicology combined with cellular and molecular biology. Among these methods, mouse lymphoma thymidine kanase (tk) gene forward mutation assay, single cell gel electrophoresis (comet assay) and transgenic animal and cell line model as a target gene of lac I (Big Blue) and lac Z (Muta Mouse) gene mutation are newly introduced based on molecular toxicological approaches. The mouse lymphoma tk$\^$+/-/ gene assay (MOLY) using L5178Y tk$\^$+/-/ mouse lymphoma cell line is one of the mammalian forward mutation assays, and has many advantages and more sensitive than hprt assay. The target gene of MOLY is a heterozygous tk$\^$+/-/ gene located in 11 chromosome, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. The comet assay is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakages in mammalian cells, Also, transgenic animal and cell line models, which have exogenous DNA incorporated into their genome, carry recoverable shuttle vector containing reporter genes to assess endogenous effects or alteration in specific genes related to disease process, are powerful tools to study the mechanism of mutation in vivo and in vitro, respectively. Also in vivo acridine orange supravital staining micronucleus assay by using mouse peripheral reticulocytes was introduced as an alternative of bone marrow micronucleus assay. In this respect, there was an International workshop on genotoxicity procedure (IWGTP) supported by OECD and EMS (Environmental Mutagen Society) at Washington D. C. in March 25-26, 1999. The objective of IWGTP is to harmonize the testing procedures internationally, and to extend to finalization of OECD guideline, and to the agreement of new guidelines under the International Conference of Harmonization (ICH) for these methods mentioned above. Therefore, we introduce and review the principle, detailed procedure, and application of MOLY, comet assay, transgenic mutagenesis assay and supravital staining micronucleus assay.

• 미생물학회지
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• 제30권2호
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• pp.141-148
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• 1992

In order to overexpress bacteriophage PRD1 DNA polymerase in E. coli cells, the 2 kb HaeII fragment was isolated from phage genomic DNA. This fragment was then cloned into pEMBL/sup ex/ 3-expression vector. A specific 57bp deletion was performed by using uracil containing ss DNA and oligonucleotide spanning each region to remove an unwanted non-coding region. After this deletion, the PRD1 DNA polymerase gene is totally under the control of the vector promoter and SD sequence. Upon heat induction, a protein with an apparent size of 68 kdal was overexpressed as an active PRD1 DNA polymerase. The expression of PRD1 DNA polymerase was about 1% of total E. coli protein.

• 미생물과산업
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• 제14권1호
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• pp.12-16
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• 1988

Allantoin 분해 유전자들중 highly inducible 한 DAL7, DUR1,2및 constitutive한 DAL5 gene의 promoter를 deletion 방법에 의해 발현에 필요한 최소 DNA seqyence 부위를 정한후 이 DNA seqyence를 다시 oligonucleotide 합성방법에 의해 합성하여 Cyc 1-LacZ expression vector에 삽입하여 효모내에서 LacZ의 발현이 삽입한 DNA sequence에 의해 영향을 받는 정도를 측정하여 (.betha.-galactosidase activity) deletion 방법에 의해 결정한 이 DNA dequence들이 직접 발현유도에 관여하는가를 조사하였다.

• Journal of Microbiology and Biotechnology
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• 제16권9호
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• pp.1338-1346
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• 2006

Ansamitocin P-3 is a potent antitumor agent produced by A. pretiosum. A deletion mutant of A. pretiosum was constructed by deleting the asm2 gene, a putative transcriptional repressor. The deletion mutant showed a 9-fold enhanced ansamitocin P-3 productivity. The response surface method with central composite design was employed to further optimize the culture medium composition for ansamitocin P-3 production by the deletion mutant. The concentrations of four medium ingredients, dextrin, maltose, cotton seed flour, and yeast extract, which have been reported as major components for ansamitocin production, were optimized through a series of flask culture experiments. The optimum concentrations of the selected factors were found to be dextrin 6.0%; maltose 3.0%; cotton seed flour 0.53%; and yeast extract 0.45%. The maximum titer of ansamitocin P-3 was 78.3 mg/l with the optimized composition, about 15-folds higher than the unoptimized titer of 5.0 mg/l obtained with YMG medium.

• 한국임상수의학회지
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• 제32권1호
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• pp.1-4
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• 2015

개의 10번 염색체에 존재하는 Copper metabolism domain containing 1 (COMMD1) 유전자는 체내 구리 대사를 조절하는 COMMD1 단백질을 합성한다. COMMD1 유전자의 exon 2 결손변이는 단백질의 결핍을 유발하여 베들링턴 테리어 견종에서 상염색체 열성 유전질환인 구리 중독증을 일으킨다. 본 증에 이환된 개체는 담즙을 통한 구리의 배설이 저해되어 간 내에 구리가 축적된다. 본 연구에서는 국내 베들링턴 테리어 257두(수컷 109두, 암컷 148두) 혈액 시료를 사용하여 genomic DNA를 추출하였다. 유전자 결손변이의 분자생물학적 진단을 위해 다중 중합효소 연쇄반응법(multiplex PCR)을 이용하여 COMMD1 유전자의 exon 2 결손 발생 및 그 빈도를 조사하였다. 베들링턴 테리어 257두에서, 정상유전자 동협접합자가 131두(51%), 이형접합자가 108두(42%), 변이유전자 동형접합자가 18두(7%)로 확인되었다. 본 연구를 통해 한국 베들링턴 테리어 개체군의 유전변이 발생 및 그 빈도를 확인하였고, 이는 국내 베들링턴 테리어 개체군의 유전자 선택적 교배계획 설립 및 변이 유전자 확산을 예방하기 위한 기초 자료로서 의의가 있다.

• 식물조직배양학회지
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• 제25권4호
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• pp.237-243
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• 1998

야생종 토마토의 자가불화합성에 관여하는 S RNase유전자의 조직특이적 발현 양상을 조사하기 위하여 $\textrm{S}_{11}$ 및 $\textrm{S}_{12}$ allele에 속하는 RNase 유전자의 Promoter영역에 대한 염기 서열을 비교 분석한 결과, 전사개시점에서 상류측으로 350-500bp사이에서 양쪽 allele의 Promoter간에 상동성을 나타내는 3부분과 direct repeat sequence를 발견하였다. Promoter영역에서 이러한 부분이 S RNase 유전자가 화주특이적으로 발현하는데 영향을 줄 것으로 예상하고, 이들 영역을 중심으로 6종류의 deletion fragment를 만들어 GUS 유전자에 연결하여, 토마토의 생식조직에 microprojectile bombardment를 수행하였다. 그 결과 토마토 자가불화합성에 관여하는 S RNase 유전자의 promoter는 TATA box를 포함한 127 bP만으로도 화주조직 특이적 발현을 조절할 수 있었다. 또한 S RNase 유전자의 promoter영역내에는 토마토 화변, 자방과 심피조직들에서 negative 혹은 positive로 유전자의 발현을 유도하는 부분이 발견되었다.

• Journal of Microbiology and Biotechnology
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• 제18권11호
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• pp.1797-1802
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• 2008

Saccharomyces cerevisiae was metabolically engineered to improve 1,2-propanediol production. Deletion of the tpil (triosephosphate isomerase) gene in S. cerevisiae increased the carbon flux to DHAP (dihydroxylacetone phosphate) in glycolysis, resulting in increased glycerol production. Then, the mgs and gldA genes, the products of which convert DHAP to l,2-propanediol, were introduced to the tpil-deficient strain using a multicopy plasmid. As expected, the intracellular level of methylglyoxal was increased by introduction of the mgs gene in S. cerevisiae and that of 1,2-propanediol by introduction of both the mgs and gldA genes. As a result, 1.11 g/l of 1,2-propanediol was achieved in flask culture.