• Korean Journal of Microbiology
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• v.42 no.2
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• pp.142-148
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• 2006

In order to develop chitosanase for the production of chitosan oligosaccharides, a chitosanase-producing bacterium was isolated from the traditional fermented soybean, Meju, and identified as Bacillus amyloliquefaciene MJ-1. The cloned chitosanase gene, 825 bp in size, encoded a single peptide of 274 amino acids with a estimated molecular mass of 30.9 kDa. The deduced amino acid sequence showed significant homology with microbial chitosanases. The recombinant chitosanase was expressed in Escherichia coli upon induction with isopropyl-D-thiogalactopyranoside, and purified using $Ni^{2+}-NTA$ agarose column chromatography. The maximal activity of the recombinant chitosanase is at pH 5.0 and $60^{\circ}C$. The recombinant chitosanase is stable between pH 5.0 and pH 7.0 at $37^{\circ}C$ for 30 min, and more than 75% of the activity still remain at $80^{\circ}C$ for 30 min incubation.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.670-676
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• 2017

Recently, mass mortality of the young abalone Haliotis discus hannai has occurred in commercial seed production farms in Korea. The mortality rate was above 50% of the total cultured organisms in the farm, and the shell length of the moribund organisms was about 3cm. The mortal phenomenon was that the young abalones were weakly scattered on the bottom of the pond from the attachment matrix, or that they could not be moved back to their normal positions. The diseased farmed Pacific abalone had abdominal edema. From the edema in the moribund individuals, three bacterial strains were isolated and all the strains were identified as Vibrio harveyi. These strains were compared with thirty six strains isolated from the fish. The results was that the Vibrio harveyi from the fish were sorted into genogroup A or B; however, the three strains of the diseased farmed Pacific abalone were sorted into genogroup A and the new genogroup C. The identical mortality and pathological symptoms of the naturally infected organisms were reproduced by artificial infection with WA AG-1 and WA CS-5 strains. The $LD_{50}$ of WA AG-1 and WA CS-5 were each $1.0{\times}10^3cfu\;animal^{-1}$ and $1.7{\times}10^4cfu\;animal^{-1}$.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.59-66
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• 2001

This study was conducted to elucidate phylogenetic relationships and genetic characterization of silkworms that might be recognized as the Korean native strains. Genetic characterization in isozymes and the proteins of larval hemolymph of 17 silkworms were observed by acrylamide gel eletrophoresis, on 12 genes; Bph, Bes, les, Amy-hc, Ict-A, -B, -D,-E,-H, Pfl, Pst, Lp. Gene frequencies in each locus were compared other geographic strains. Korean native strains were remarkably different from others considered as the genetic characterization of Korean native strains. Phylogenetic relationships in Korean native strains were analysed using RAPD-PCR markers. A total of 40 primers were used and 346 bands of amplified DNA were generated from geographic strains. Genetic similarity based on the RAPD bands was used to construct phylogenetic dendrogram based on analysis of bard sharing data of amplified markers. Genetic similarity ranged from 0.595 to 0.860. In the genetic relationship based on dendrogram, they were classified into Bombyx mori group (including 16 domesticated silkworm strains) and B. mandarina group. The Bombyx mori group was separated into three sub-groups at the genetic similarity of 0.6930, including Korean, Japanese and Chinese groups. According to this result, the Korean native variety can be considered as a clearly different variety from other geographic strains. It may be concluded that the Korean native strains are also one of original geographic variety such as Japanese, Chinese, etc.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.533-536
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• 2019

Recombinant baculoviruses are widely used to express heterologous genes in cultured insect cells. Recombinant baculoviruses can serve as gene-transfer vectors for expression of recombinant proteins in a wide range of mammalian cell types. Baculovirus system has significant benefits in view of safety, large-scale, and high level of gene expression. In this study, baculoviral vectors which were reconstructed from pOPINEneo-3C-GFP vector, were recombined with cytomegalovirus (CMV) promoter, green fluorescent protein (GFP), and p53 with NcoI and XhoI. These recombinant vectors were infected with various cells and cell lines. The baculovirus vector thus developed was analyzed by comparing the metastasis and expression of the recombinant genes with conventional vectors. These results suggest that the baculovirus vector has higher efficiency in metastasis and expression than the control vector. This work was supported by a grant from Mid-Career Researcher Program(NRF-2016R1A2B4016552) through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT & Future Planning(MSIP).

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.389-396
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• 2020

Lentinula edodes is one of the most widely consumed edible mushrooms in Korea. Mating in L. edodes is regulated by a tetrapolar system, and two unlinked genetic loci, A and B, are known to be major determinants of the mating types, as reported in other heterothallic basidiomycetes. The A locus of L. edodes encodes a pair of homeodomain (HD) transcription factors. The highly variable N-termini of these HD transcription factors contribute to the diversity among the A mating types. In this study, we developed a cleaved amplified polymorphic sequence (CAPS) marker to discriminate 11 different A mating type alleles predominant among both cultivated and wild strains. Amplification of the variable region of the A locus followed by digestion with HaeIII and EcoRI restriction enzymes enabled successful discrimination among the 11 A mating type alleles. We also evaluated the applicability of this method in the identification of two A mating types of a dikaryotic strain.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.128-132
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• 2006

관절염이 일어나는 정확한 기전은 아직까지 잘 규명되어 있지 않으나 일반적으로 cytokine, chemokine을 비롯한 여러 가지 조절 물질들 사이의 미묘한 균형이 깨어지는 일이 주된 요인으로 추정되고 있다. 사람의 경우 염증이 일어난 관절 조직에서 활막 세포(synovial fibroblast)는 여러 염증성 사이토카인들을 분비하기도 하며 또 한편 이들 cytokine의 target 세포로 이들의 자극에 대하여 정상인의 그것과 다른 증식 및 활성화 반응을 보이는 등, 다양한 측면에서 관절염증의 유발에 기여하는 것으로 보여진다. 따라서 활막세포 활성화 경로를 DNA Microarray chip을 이용하여 세포 및 분자 수준에서 밝혀 이를 차단할 수 있는 자연물질(natural product)를 선별함으로써 항생제나 스테로이드를 사용하지 않고 돼지의 관절염을 효과적으로 치료 또는 예방할 수 있는 방법을 모색하고자 한다. 6.6kg의 암컷 Yorkshire와 수컷 Landrace의 교배잡으로 왼쪽 뒷다리 슬관절에 십자인대를 파열하여 관절염을 유발하고 8주간 성장을 시킨 후 정상 슬관절과 관절염이 유발된 슬관절의 활막세포로부터 total RNA를 추출한 후 affymetrix Gene chip을 제작하여 Geneplex소프트웨어를 이용하여 데이터를 분석하였다. 분석 결과 unknown 유전자 962개를 포함하여 유전자 발현이 증가된 유전자는 총 1,059개 였으며, unknown 유전자 564개를 포함하여 유전자 발현이 증가된 유전자는 총 639개를 얻었다. 이러한 돼지 관절염에서의 활막세포에 의한 유전적 발현 양상으로부터 molecular function, biological process, pathway등을 이용하여 관절염 지표를 작성할 수 있다.분별을 성공적으로 수행하였다.(p<0.05), 맛, 연도, 다즙성 및 전체적인 기호성은 유의한 차이가 없었다.자체를 악하다고 볼 수 없고 더구나 구원을 이 세상에서의 이탈로 볼 수 없다. 진정한 구원이란 원래 하나님이 보시기에 아름다웠던 그 세상으로의 회복을 포함한다. 이런 면에서 하나님 주권 신앙 하에서 구원이란 전 인격적인 구원, 전 우주적인 구원이 된다. 그렇기 때문에 성도는 세상의 삶과 학문, 예술, 정치, 경제, 사회를 포함한 모든 분야를 하나님의 뜻 가운데서 그 원래의 목적에 부합할 수 있도록 회복시키는 일에 적극 참여해야 한다.자체가 이를 주도하기는 사실 어려움이 있다. 그리고 대형유통점이 영업행위를 영업시간제한에서부터 출점제한에 이르기까지 규제하는 건은 심사숙고하여야 한다. 대형유통점이 국가경제 및 지역사회에 미치는 영향이 부정적인가 긍정적인가에 대해 국내외 학계와 업계에서 여전히 많은 논란이 있기 때문이다. 정부와 지자체에 의한 시장개입은 반드시 필요한 경우에 한해 합당한 방법에 의해 이루어져야 한다. 대형유통점에 대한 규제는 지역사회에 미치는 영향을 다면적으로 평가한 결과에 근거하여 이루어져야 할 것이다. 대부분의 지자체는 체계적인 평가시스템과 객관적인 통계 자료를 갖고 있지 못한 실정이다. 향후 가장 시급한 과제는 시장개방 이후 지난 10년간 대형유통점이 지역사회에 미친 영향에 관한 광범위한 통계자료를 수집하고 이를 체계적으로 분석하여 정책방향을 올바르게 설정하는 것이라 할 수 있다.i와 K. pneumoniae가 존재하며 확산 중임을 시사한다. 앞으로 CTX-M형 ESBL의 만연과 변종 CTX-M형 ESBL의 출연을 감시하기 위한 정기적인 연구와 조사가 필요한 것으로 생각한다., A2-1, B1-1, B2-1의 경우, 강우 일수 감소 이전과

• Mycobiology
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• v.51 no.1
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• pp.36-48
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• 2023

Xanthoria elegans is a lichen symbiosis, that inhabits extreme environments and can absorb UV-B. We reported the de novo sequencing and assembly of X. elegans genome. The whole genome was approximately 44.63 Mb, with a GC content of 40.69%. Genome assembly generated 207 scaffolds with an N50 length of 563,100 bp, N90 length of 122,672 bp. The genome comprised 9,581 genes, some encoded enzymes involved in the secondary metabolism such as terpene, polyketides. To further understand the UV-B absorbing and adaptability to extreme environments mechanisms of X. elegans, we searched the secondary metabolites genes and gene-cluster from the genome using genome-mining and bioinformatics analysis. The results revealed that 7 NR-PKSs, 12 HR-PKSs and 2 hybrid PKS-PKSs from X. elegans were isolated, they belong to Type I PKS (T1PKS) according to the domain architecture; phylogenetic analysis and BGCs comparison linked the putative products to two NR-PKSs and three HR-PKSs, the putative products of two NR-PKSs were emodin xanthrone (most likely parietin) and mycophelonic acid, the putative products of three HR-PKSs were soppilines, (+)-asperlin and macrolactone brefeldin A, respectively. 5 PKSs from X. elegans build a correlation between the SMs carbon skeleton and PKS genes based on the domain architecture, phylogenetic and BGC comparison. Although the function of 16 PKSs remains unclear, the findings emphasize that the genes from X. elegans represent an unexploited source of novel polyketide and utilization of lichen gene resources.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.46-46
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• 2003

Interleukin-10 (IL-10) is a homodimeric protein with a wide spectrum of anti-inflammatory and immune activities. It inhibits cytokine production and expression of immune surface molecules in various cell types. The transgenic mice carrying the human IL-10 gene in conjunction with the bovine $\beta$-casein promoter produced the human IL-10 in milk during lactation. Transgenic mice were generated using a standard method as described previously. To screen transgenic mice, PCR was carried out using chromosomal DNA extracted from tail or toe tissues with a primer set. In this study, stability of germ line transmission and expression of IL-10 gene integrated into host chromosome were monitored up to generation F15 of a transgenic line. When female mouse of generation F9 was crossbred with normal male, generation F9 to F15 mice showed similar transmission rates (66.0$\pm$20.13%, 61.5$\pm$16.66%, 41.1$\pm$8.40%, 40.7$\pm$20.34%, 61.3$\pm$10.75%, 49.2$\pm$18.82%, and 43.8$\pm$25.91%, respectively), implying that the IL-10 gene can be transmitted stably up to long term generation in the transgenic mice. For ELISA analysis, IL-10 expression levels were determined with an hIL-10 ELISA and a mIL-10 ELISA kit in accordance with the supplier's protocol. Expression levels of human IL-10 from milk of generation F9 to F13 mice were 3.6$\pm$1.20 mg/ml, 4.2$\pm$0.93 mg/ml, 5.7$\pm$1.46 mg/ml, 6.3$\pm$3.46 mg/ml, and 6.8$\pm$4.52 mg/ml, respectively. These expression levels are higher than in generation F1 (1.6 mg/ml) mice. We concluded that transgenic mice faithfully passed the transgene on their progeny and successively secreted target proteins into their milk through several generations, although there was a little fluctuation in the transmission frequency and expression level between the generations.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.227-237
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• 2003

Purpose: The human chronic myelogenous leukemia cell line, K562, expresses the chimeric bcr-abl oncoprotein, whose deregulated protein tyrosine kinase activity antagonizes via DNA damaging agents. Previous experiments have shown that nanomolar concentrations of herbimycin A (HWA) coupled with X-irradiation have a synergistic effect in inducing apoptosis in the Ph-positive K562 leukemia cell line, but genistein, a PTK inhibitor, is non selective for the radiation-induced apoptosils on $p210^{bcr/abl}$ protected K562 cells. In these experiments, the cytoplasmic signal transduction pathways, the Induction on a number of transcription factors and the differential gene expression in this model were investigated. Materials and Methids: K562 cells in the exponential growth phase were used in this study. The cells were irradiated with 0.5-12 Gy, using a 6 Mev Linac (Clinac 1800, Varian, USA). Immediately after irradiation, the cells were treated with $0.25/muM$ of HMA and $25/muM$ of genistein, and the expressions and the activities of abl kinase, MAPK family, NF- kB, c-fos, c-myc, and thymidine kinase1 (TK1) were examined. The differential gene expressions induced by PTK inhibitors were also investigated. Results: The modulating effects of herbimycin A and genistein on the radiosensitivity of K562 cells were not related to the bcr-abl kinase activity. The signaling responses through the MAPK family of proteins, were not involved either in association with the radiation-induced apoptosis, which is accelerated by HMA, the expression of c-myc was increased. The combined treatment of genistein, with irradiation, enhanced NF- kB activity and the TK1 expression and activity. Conclusion: The effects of HMA and genistein on the radiosensitivity on the K562 cells were not related to the bcr-abl kinase activity in this study, another signaling pathway, besides the WAPK family responses to radiation to K562 cells, was found. Further evaluation using this model will provide valuable information for the optional radiosensitization or radioprotection.

• Tuberculosis and Respiratory Diseases
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• v.55 no.1
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• pp.41-58
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• 2003

Background : The resurgence of tuberculosis and the widespread emergence of multidrug-resistant M. tuberculosis have emphasized the importance of rapid and accurate diagnostic procedures. Recently, the oligonucleotide chip has proven to be a useful tool in the rapid diagnosis of infectious diseases. The purpose of this study was to rapidly and accurately detect specific mutations in the rpoB, katG and rpsL genes associated with rifampin, isoniazid and streptomycin resistance in M. tuberculosis, respectively, using a single oligonucleotide chip. Method : For detection of drug-resistance, 7 wild-type and 13 mutant-type probes for rifampin, 2 wild-type and 3 mutant-type probes for isoniazid, and 2 wild-type and 2 mutant-type probes for streptomycin were designed and spotted onto glass slides. Fifty-five cultured samples of M. tuberculosis were amplified by PCR, and then underwent hybridization and scanning. Direct sequencing was done to verify the results from the oligonucleotide chip and to analyze the types of mutations. Result : Thirty-five cases out of 40 rifampin-resistant strains(~88%) had mutations in the rpoB gene. One case had a new mutation(D516F, GAC R TTC) and another known mutation together. Twenty cases out of 42 isoniazid-resistant strains(~50%) had mutations in the katG gene, while 7 cases out of 9 streptomycin-resistant strains(~78%) had mutations in the rpsL gene. From these results, the oligonucleotide chip was confirmed to be able to detect the most frequent mutations from the genes associated with rifampin, isoniazid and streptomycin resistance. The results proved that the drug-resistance detection probes were specific. When the results from the oligonucleotide chip and DNA sequencing were compared, the types of mutations were exactly matched. Conclusion : The diagnostic oligonucleotide chip with mutation specific probes for drug resistance is a very reliable and useful tool for the rapid and accurate diagnosis of drug resistance against rifampin, isoniazid and streptomycin in M. tuberculosis infections.