• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.212-216
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• 2015

Oseltamivir, also known as Tamifu, is an inhibitor of neuraminidase protein which plays an essential role in proliferation and replication of influenza virus. Binding to the active site of neuraminidase, the oseltamivir prevents the protein from enzyme reaction. Conformational change of the protein(neuraminidase) should be accompanied by the enzyme reaction, but the drug inhibits the protein to deform. In this study, we examine the influence of oseltamivir on protein's conformational change in the structural and mechanical point of view. Finite element analysis of the protein can be an useful approach to investigate the influence of oseltamivir on the deformation of a protein. We suggest the finite element based protein model, and then perform the linear static analysis with the displacement loading condition based on the first two largest motion which can be obtained from the normal mode analysis. The results show that it takes more energy to change shape of the protein with an oseltamivir attached than the protein without an oseltamivir.

• 미생물학회지
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• 제29권1호
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• pp.25-33
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• 1991

Antiviral activities of papaverine and nucleoside analogs, 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine (DHPG) and acyclovir, against human cytomegalovirus (HCMV) infection were compared in vitro. Papaverine and DHPG were effective in reducing infectious HCMV yields with $ED_{50}{\s}$ (effective dose 50: the concentraion at which 50% of virus yields was obtained) of approximately 1.02 and $0.45{\mu}{\M}$, respectively; while acyclovir was less effective with an $ED_{50}$ of about $10.4{\mu}{\M}$The relative cytotoxicity of these drugs was evaluated under the same conditions used to measure infectious HCMV yields. Papaverine and DHPG demonstrated little cellular toxicity as measured by their effect on the viability of confluent cells at concentrations in the range of those demonstrating potent inhibition of HCMV replication. Similarly, protein synthesis was largely unaffected by these drugs in stationary mock-infected cells as measured by the incorporation of isotopically labelled amino acids. In contrast, cellular DNA synthesis was invariably reduced in the presence of either drug. HCMV-specific DNA synthesis was also strongly inhibited by papaverine and DHPG.

• Clinical and Experimental Pediatrics
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• 제55권12호
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• pp.491-493
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• 2012

Cytomegalovirus (CMV)-associated esophageal ulcer is rare in immunocompetent infants. The presence of inclusion bodies and immunohistochemical staining for CMV in biopsy specimens obtained during esophagogastroduodenoscopy (EGD) indicate that such ulcers occur because of CMV infection. A 7-week-old female infant who experienced frequent vomiting and feeding intolerance was diagnosed with a massive CMV-associated ulcer in the distal esophagus. The ulcer improved after conservative treatment using proton-pump inhibitors; however, ganciclovir was not administered. In a follow-up EGD biopsy specimen, no CMV inclusion bodies were present, and immunohistochemical staining results for this virus were negative. The presence of CMV inclusion bodies indicates active viral replication. If persistent inclusion bodies or positive immunohistochemical staining for CMV is observed in follow-up biopsy specimens, ganciclovir may be used to treat CMV-associated esophageal ulcers.

• International journal of advanced smart convergence
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• 제7권1호
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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.

• 미생물학회지
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• 제25권3호
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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.

• Applied Microscopy
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• 제52권
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• pp.11.1-11.9
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• 2022

Zoonotic poxvirus infections pose significant threat to human health as we have witnessed recent spread of monkeypox. Therefore, insights into molecular mechanism behind poxvirus replication cycle are needed for the development of efficient antiviral strategies. Virion assembly is one of the key steps that determine the fate of replicating poxviruses. However, in-depth understanding of poxvirus assembly is challenging due to the complex nature of multi-step morphogenesis and heterogeneous virion structures. Despite these challenges, decades of research have revealed virion morphologies at various maturation stages, critical protein components and interactions with host cell compartments. Transmission electron microscopy has been employed as an indispensable tool for the examination of virion morphology, and more recently for the structure determination of protein complexes. In this review, we describe some of the major findings in poxvirus morphogenesis and the contributions of continuously advancing electron microscopy techniques.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2021년도 춘계학술대회
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• pp.3-3
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• 2021

The ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not only influenced over 1.26 billion people but also caused 2.77 million deaths worldwide (as of March 28, 2021). The vaccination could be the most efficient strategy to prevent SARS-CoV-2 infection. However, the continuous emergence of novel variants such as VUI-202012/01 (United Kingdom) and 501.V2 (South Africa) raises huge concerns about the effectiveness of the vaccine designed to target the original virus strain. Since ancient times regardless of the East and West, the plants which refered in this presentation have been consumed not only as food but also as a natural medicine to treat diverse diseases including infectious diseases. Importantly, these plants contain secondary metabolites that display antiviral activity involved in the inhibition of viral adsorption, penetration, and replication. Also, plant-derived natural medicines are expected to have a wider range of efficacy and fewer side effects than synthetic medicine, discovering novel plant-based viral agents would be a promising strategy to fight against SARS-CoV-2.

• Journal of Microbiology and Biotechnology
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• 제23권8호
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• pp.1076-1083
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• 2013

Seventeen compounds derived from traditional Chinese medicines (TCMs) were tested for their antiviral activity against porcine reproductive and respiratory syndrome virus (PRRSV) in vitro. Visualization with the cytopathologic effect (CPE) assay and the 3-(4, 5-dimethyithiazol-2-yl)-2,5-diphenyltetrazolium bromide test were used to determine the 50% cytotoxic concentration ($CC_{50}$) and 50% effective concentration ($EC_{50}$) in cultured Marc-145 cells. Among the tested compounds, chlorogenic acid and scutellarin showed potential anti-PRRSV activity. The $EC_{50}$ values were $270.8{\pm}14.6{\mu}g/ml$ and $28.21{\pm}26.0{\mu}g/ml$ and the selectivity indexes were >5.54 and 35.5, respectively. The time-of-addition and virucidal assay indicated that the anti-PRRSV activity of the two compounds could be due to their inhibiting the early stage of virus replication and/or inactivating the virus directly. The inhibition of the virus attachment was not observed in the adsorption inhibition assay. The inhibition ratios of chlorogenic acid and scutellarin were, respectively, 90.8% and 61.1% at the maximum non-cytotoxic concentrations. The results have provided a basis for further exploration of their antiviral properties and mechanisms in vivo. We believe that the chlorogenic acid and scutellarin have a great potential to be developed as new anti-PRRSV drugs for clinical application.

• 생명과학회지
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• 제30권4호
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• pp.402-409
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• 2020

신경괴사증바이러스(NNV)는 25 nm의 작은 입자 크기에 RNA1 (3.4 kb, RdRp), RNA2 (1.4 kb, capsid protein) 두 가닥의 RNA를 유전정보를 가진다. NNV는 1980년대 말 처음 보고된 이후 전 세계적으로 120여종의 어류에 감염을 일으키며 심각한 피해를 일으키고 있는 바이러스이다. NNV 감염에 의한 피해를 최소화하고 효율적인 백신들을 개발하기 위해서는 무엇보다 NNV 감염에 따른 세포내 신호전달체계를 이해할 필요가 있다. NNV는 세포내 감염 이후 숙주가 가진 바이러스 복제에 필요한 요소들을 이용할 수 있도록 숙주세포의 cell cycle arrest 등의 기작을 이용하는 것으로 알려졌다. 반면에 숙주 세포는 NNV와 감염된 세포를 제어하기 위해 RIG-1-like receptor signaling pathway 등을 통해 NNV 감염을 인지한 다음 IFN signaling pathway를 통해 항바이러스 작용에 필요한 ISG들을 발현시킨다. 또한 감염된 세포들을 사멸시키기 위해 ER stress를 통한 unfolded protein response (UPR), mitochondria-mediated cell death 작용을 통해 감염된 세포의 apoptosis를 유발한다. NNV 감염 기작에 대한 세포신호전달연구는 아직 초기단계이며 검증해야 할 pathway들이 아직도 많이 남아있는 상황이다. 따라서 NNV 감염과 연관된 다양한 세포신호전달체계를 탐색하고 질병 특이적인 세포신호전달체계를 이해함으로써 신속하고 정확한 진단법 및 백신 개발에 많은 도움이 될 것으로 생각된다.

• Applied Biological Chemistry
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• 제38권5호
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• pp.435-439
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• 1995

바이러스 살충제의 개발을 위한 기초 자료로서 Hyphantria cunea nuclear polyhedrosis virus(HcNPV)의 일부 특성과 병원성을 조사하였다. HcNPV는 Spodoptera frugiperda (Sf)세포의 핵에서 복제 되었으며, 바이러스를 감염 시켰을 경우 감염 24시간 후에 prepolyhedra 형성이 관찰 되었고, 감염 48시간 후에는 성숙된 많은 polyhedra가 전체세포에서 관찰 되었으며, 감염 72시간 후에는 polyhedra가 세포밖으로 방출 되었다. 또한 세포는 부유 배양에서 잘 성장 하였으며, 바이러스에 감염되기 전의 세포 배양액은 pH가 6.35이었으나 이주 점차 증가하여 감염 120시간 후에는 pH가 6.77이었다. Polyhedra inclusion body(PIB)를 설탕 밀도구배 원심 분리한 결과 $50{\sim}55%$ 부근에서 벤드가 형성 되었고, polyhedra는 도립 현미경과 전자 현미경하에서 관찰한 결과 대부분 4변형의 6면체(tetragonal hexahedron) 이었고, PIB의 크기는 평균 $2.5{\mu}m$이었다. 또한 감염 48시간 후에 polyhedra 속에는 다발을 형성한 비리온이 봉입 되어 있었다. 흰불나방 유충에대한 병원성 시험에서는 4령에서 보다는 2령과 3령의 유충에서 치사율이 높았고, $1.5{\times}10^{9}{\sim}l.5{\times}10^{7}PIB/ml$로 섭식시킨 구룹에서는 2령과 3령 유충에서 90% 이상의 치사율을 나타 내었다.