• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.59-65
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• 2005

Poly-${\gamma}$-glutamic acid (PGA) is an unusual anionic polypeptide and has great potential as an environmentally and industrially significant biodegradable material. A new ${\gamma}$-PGA producer, Bacillus mesentericus MJM1, with high production capacity was isolated from Korean domestic Chungkuckjang bean paste. It produced ${\gamma}$-PGA at the level of 10 g/l in suitable media. The viscosities of 5% initially extracted mucin and purified ${\gamma}$-PGA solutions were 660 cps and 600 cps, respectively. The produced ${\gamma}$-PGA polymer consisted of 2,000 glutamic acid residues with even proportion of L and D types with molecular mass of about 200- 300 kDa. Bacillus mesentericus MJM1 displayed ${\gamma}$-glutamyltranspeptidase (${\gamma}$-GTP) activity that is known to play a key role in ${\gamma}$-PGA biosynthesis. The ${\gamma}$-GTP coding region was located on the plasmid of 5.8 kb. The plasmid, named pMMH1, is a rolling-circle replication (RCR) plasmid and additionally contained a replication origin and type I signal peptidase (sipP) coding region.

• Journal of Forest and Environmental Science
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• v.28 no.4
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• pp.278-281
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• 2012

Comparative sequence analyses were conducted on complete mtDNA sequences from four small mammal species in Korea and revealed the presence of 30 well conserved sequences in various regions of the complete mtDNA sequences. The conserved sequences were found in 9 regions in protein coding genes, 10 regions in tRNA genes, 10 in rRNA genes, one region in replication origin and 2 regions in D loop. They could be used to design primers for amplifying complete mtDNA sequences of small mammals.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.316-316
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• 1994

자외선 등에 의한 DNA 합성억제의 회복과정에서의 기작을 규명하기 위하여 자외선에 의하여 억제되었던 DNA 합성이 새로운 replication origin을 사용하는 지를 DNA 복제가 일어나는 장소로 알려진 nuclear matrix와 연관지어서 살펴 보았다. 자외선 조사후 새로 합성된 DNA 분자들의 크기는 시간이 경과하여도 대조군의 DNA 분자들의 크기보다 작았으나 그 성장 양상은 차이가 얼었고, 자외선이 조사된 세포에서 parental DNA의 부가적인 결합이 DNA 합성률의 회복에 필요함을 알 수 있었다. 또한 자외선 상해의 회복과정에서 생기는 알카리 민감성 부위는 RNA linker에 의해 생겨남을 알 수 있었다. 이상의 결과들을 종합하여 보면, 자외선에 의해 pyrimidine dimer가 생기면 첫째로 절제회복에 의해 제거되어지지만, 남아 있는 pyrimidine dimel에 의해서 DNA 복제억제는 여전히 억제되어 있다. DNA 복제억제의 회복은 새로운 복제원점이 활성화되어 nuclear matrix에 결합하여 새로운 DNA 합성이 시작됨으로써 이루어진다. 이때 RNA linker는 복제진행시 DNA 상의 gap으로 생긴 tyopological strain을 제거하는데 이용되어진다.

• International journal of advanced smart convergence
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• v.7 no.1
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• pp.48-63
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• 2018

The combination of Simian Virus40 (SV40)'s large T antigen with its replication origin is commonly used in molecular studies to enhance the expression of heterogeneous genes through multiplying the plasmid copy number. There are no reports related to the impact of the SV40 T antigen on plant, multiple fissional, cell-type. This study explores the response of two multiple-fission microalgal cells, Scenedesmus quadricauda and Chlorella vulgaris, to the expression of the T-antigen, with aim of applying SV40 T-antigen to increase the expression efficiency of foreign genes in the two species. Different levels of low-expression have been constructed to control the expression of SV40 T antigen using three heterogenous promoters (NOS, CaMV35S, and CMV). Chlorella cultures showed slowdown in the growth rate for samples harboring the T antigen under the control of CaMV35S and CMV promoters, unlike Scenedesmus cultures which showed no significant difference between samples and could have silenced the expression.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.165-172
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• 1987

An expression vector in a mammalian cell was constructed using the origin of replication (OR) and the promoters of SV40. The plasmid pSVOE was constructed by inserting SV40 DNA fragment (1, 118bp) containing SV40 OR and promoters into pBR322-1, and then a multiple cloning sequence was inserted at the immediate downstream of the late promoter of SV40 in the pSVOE vector. The plasmid was named pSVML. As a selection marker, thymidine kinase gene of herpes simplex virus with its promoter was inserted into EcoRI site of pSVML and the recombinant was named pSVML-TKp. To test the expression capacity of foreigen gene inserted at the multiple cloning site of pSVML, the thymidine kinase gene without its own promoter was inserted at the BamHI site of pSVML. The recombinant was named pSVML-TK. These plasmids, pSVML-TKp and pSVML-TK, were transfected into COS cells with calcium phosphate precipitation method. The thymidine kinase activity was significantly increased in both transfected cells.

• Genomics & Informatics
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• v.18 no.3
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• pp.32.1-32.7
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• 2020

The mitochondrial genome of a species is an essential resource for its effective conservation and phylogenetic studies. In this article, we present sequencing and characterization of the complete mitochondrial genome of a threatened labeonine fish, Cirrhinus reba collected from Khulna region of Bangladesh. The complete mitochondrial genome was 16,597 bp in size, which formed a circular double-stranded DNA molecule containing a total of 37 mitochondrial genes (13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes) with two non-coding regions, an origin of light strand replication (OL) and a displacement loop (D-loop), similar structure with other fishes of Teleostei. The phylogenetic tree demonstrated its close relationship with labeonine fishes. The complete mitogenome of Cirrhinus reba (GenBank no. MN862482) showed 99.96% identity to another haplotype of Cirrhinus reba (AP013325), followed by 90.18% identity with Labeo bata (AP011198).

• BMB Reports
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• v.56 no.6
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• pp.335-340
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• 2023

During normal physiological and abnormal pathophysiological conditions, all cells release membrane vesicles, termed extracellular vesicles (EVs). Growing evidence has revealed that EVs act as important messengers in intercellular communication. EVs play emerging roles in cellular responses and the modulation of immune responses during virus infection. EVs contribute to triggering antiviral responses to restrict virus infection and replication. Conversely, the role of EVs in the facilitation of virus spread and pathogenesis has been widely documented. Depending on the cell of origin, EVs carry effector functions from one cell to the other by horizontal transfer of their bioactive cargoes, including DNA, RNA, proteins, lipids, and metabolites. The diverse constituents of EVs can reflect the altered states of cells or tissues during virus infection, thereby offering a diagnostic readout. The exchanges of cellular and/or viral components by EVs can inform the therapeutic potential of EVs for infectious diseases. This review discusses recent advances of EVs to explore the complex roles of EVs during virus infection and their therapeutic potential, focusing on HIV-1.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.319-327
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• 1987

In order to develop useful plasmid vectors for Zymomonas cells, attempts were made to isolate natural plasmids from Z. mobilis ATCC10988. Among a few plasmids isolated, a small plasmid of 3.9 Kb size was chosen and designated as pZM3. By introducing the replication origin of pZM3 into pBR325, a hybrid plasmid vector of 8.4 Kb size, pHZ22, was constructed. This vector contained chloramphenicol resistant gene as a selectable marker and proved to be conjugally transmissible and stably maintained in Z. mobilis. Tetracycline resistant gene was isolated from RP4 and introduced into pHZ22 to make a new vector called pHZT224 of 10.7 Kb size. Through n series of experiments, it was evident that these plasmid vectors containing selectable markers of chloramphenicol and tetracycline resistance were shuttle vectors functional in Z. mobilis as well as E. coli.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1190-1196
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• 2006

This experiment was carried out to investigate the effects of Korean, Japanese and Chinese green tea on laying performance and egg quality in hens. A total of 168 "Tetran Brown" hens aged 40 weeks were assigned to 7 treatments in a completely randomized design. Each treatment had 4 replicates accommodating 6 layers per replication. The seven dietary treatments were: 1) control diet with no green tea added, 2) diet containing 1.0% Korean green tea (1.0% KGT), 3) diet containing 2.0% Korean green tea (2.0% KGT), 4) diet containing 1.0% Japanese green tea (1.0% JGT), 5) diet containing 2.0% Japanese green tea (2.0% JGT), 6) diet containing 1.0% Chinese green tea (1.0% CGT), and 7) diet containing 2.0% Chinese green tea (2.0% CGT). Egg production rate of the layers fed diets containing 1.0 or 2.0% green tea powders were significantly increased compared to that of the control (p<0.05). The egg weight of layers was significantly reduced in layers fed 1.0% CGT (p<0.05). The feed intake was significantly decreased in KGT and CGT groups at 2.0% inclusion levels (p<0.05). The egg shell thickness and shape index of JGT treatment was significantly lower than that of the control (p<0.05). There were no significant differences in albumen index, yolk index and Haugh unit of eggs for layers fed diets containing green tea powders regardless of origin (p>0.05). Green tea feeding to layers tended to reduce the overall cholesterol content of egg yolk. Particularly, 1.0 or 2.0% CGT significantly depressed the total cholesterol content of egg yolk (p<0.05). In conclusion, incorporation of 1.0 or 2.0% Korean, Japanese and Chinese green tea into layer diets regardless of origin had favorable effects on laying performance and egg quality profiles. Among the three green tea sources, the Chinese green tea powder had the highest reducing effect on cholesterol content in egg yolk.

• Journal of Microbiology
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• v.44 no.6
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• pp.671-673
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• 2006

A new 4.87 kb Escherichia-Pseudomonas shuttle vector has been constructed by inserting a 1.27 kb DNA fragment with a replication origin of a Pseudomonas plasmid pRO1614 into the 3.6 kb E. coli plasmid pBGS18. This vector, designated pJH1, contains an aminogly-coside phosphotransferase gene (aph) from Tn903, a lacZ' gene for $\alpha$-complementation and a versatile multiple cloning site possessing unique restriction sites for EcoRI, SacI, KpnI, SmaI, BamHI, XbaI, SalI, BspMI, PstI, SphI, and HindIII. When pJH1 was transformed into E. coli DHS${\alpha}$ and into P. putida HK-6, it was episomally and stably maintained in both strains. In addition, the enhanced green fluorescent protein (EGFP) gene which was transcriptionally cloned into pJH1 rendered E. coli cells fluorescence when its transformants were illuminated at 488 nm.