• Korean Journal of Microbiology
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• v.46 no.2
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• pp.140-147
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• 2010

Japanese encephalitis virus (JEV), a member of the mosquito-borne flaviviruses, causes epidemics of viral encephalitis in the Southeastern Asia. JEV is a small enveloped virus with a positive-sense RNA genome; the infectious virion consists of three structural proteins, namely capsid, membrane (M; a mature form of its prM precursor), and envelope proteins. Here, we investigated a role of the charged residues found at the N-terminus of the JEV M protein in virus production. Using an infectious JEV cDNA, we generated two mutant cDNAs, Mm1 and Mm2, by charged-to-alanine substitution for $E^9$ and $K^{15}K^{16}E^{17}$ residues of the M protein, respectively. By transfection of wild-type or each of the two mutant RNAs transcribed from the corresponding cDNAs, we found that Mm2, but not Mm1, had a ~3-log decrease in virus production, even though a comparable amount of all three structural proteins were produced in transfected cells. Interestingly, the prM protein expressed in Mm2 RNA-transfected cells was not recognized by the polyclonal antiserum raised against the N-terminal 44 amino acids of the wild type M protein, but reacted to the antiserum raised against the corresponding region of the mutant Mm2. Our results indicate that three charged residues ($K^{15}K^{16}E^{17}$) in JEV M protein play a role in virus production. Two polyclonal antisera specifically recognizing the wild-type or Mm2 version of the M protein would provide a useful reagent for the functional study of this protein in the virus life cycle.

• The Journal of Korean Society of Virology
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• v.28 no.4
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• pp.295-302
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• 1998

The RNA genome of poliovirus encodes a long polyprotein precursor and this polyprotein is cleaved proteolytically by viral protease to yield mature proteins. The mature proteins derived from the P1 polyprotein precursor are the component of capsids. To further delineate the process of capsid assembly and encapsidation, in a first attempt, a cell line which expresses the authentic P1 polyprotein was established. CV-1 cells were transfected with the pRCRSVS1P1 plasmid DNA which contains 5'ncr sequences, whole authentic capsid gene of poliovirus and neomycin resistance gene. These cells were treated with G418 for 3 months, and eventually G418 resistant cells were selected and formed colonies. Each colony was picked and grown in the media containing G418. DNA analysis indicated that 1 of 13 neomycin resistant cell lines (R2-18) contains whole poliovirus P1 capsid gene segment which was incorporated into the genome. Immuneprecipitation of cell lysates with sera from rabbit immunized with inactivateded Sabin type 1 particles demonstrated the constitutive expression of the poliovirus P1 capsid protein from R2-18.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.176-181
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• 1996

Aster yomena로부터 분리한 오이 모자이크 바이러스(cucumber mosaic virus) (CMV-As)의 RNA4로부터 완전한 길이의 cDNA를 합성하고 그 전체적인 염기서열(1,043 nt`s)을 결정하였다. CMV-As RNA4는 73개의 염기로 구성된 5`말단의 leader 부위, 657개의 염기로 구성된 외피단백질(coat protein) 유전자 부위 및 312개의 염기로 구성된 3` 말단의 비번역 부위로 구성되어 있음을 확인하였다. 외피단백질 유전자 부위의 염기서열을 다른 계통의 CMV와 비교해 볼 때 그 염기서열이 보전적으로 존재하고 있으나 그 외의 부분은 다양함을 확인하였다. 특히 3` 말단부위의 61개의 염기로 구성된 부위(959-1019)는 다른 계통의 CMV에서는 상당히 유사하지만 CMV-As도 다른 CMV처럼 tRNA와 유사한 구조를 역시 형성함을 확인하였다. CMV-As의 RNA4 염기서열을 다른 계통의 CMV와 비교할 때 CMV-I17F와 가장 유사하였으며(91.9%) S형의 CMV-M과는 가장 낮은 동일성을 보였다(71.1%). 외와 같은 염기성열의 비교 결과와 EcoRI 제한효소 인식부위의 존재로 미루어 CMV-As는 WT형으로 분류된다.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.287-295
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• 1995

Molecular cloning and nucleotide sequencing were undertaken for the RNA genome of gp53 antigenic region in cytopathic Singer strain of bovine viral diarrhea virus. The cloned cDNA was 939 nucleotides in length having a base composition of 31.0% A, 19.6% C, 25.5% G and 24.0% T. The sequence was corresponded to approximately 77.8%(817 bases) of predicted gp53 region and 122 bases after 3'end of gp53 region in the Singer strain when compared with NADL strain of known sequence. A single open reading frame was found in the sequence of 2nd frame and was deduced as encoding 312 amino acids.

• The Journal of Korean Physical Therapy
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• v.11 no.2
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• pp.81-92
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• 1999

중추신경계의 미주신경동쪽핵(DMV)내 유사핵분열후 신경세포로 외래 유전자를 전달하는 매개체로서 pseudorabies 바이러스(PRV)의 유전자 조작기술은 흰쥐의 결장내로 PRV를 주입시킨 후 복잡한 신경로 추적에 관한 연구에서 하나의 바이러스에 의해 얻어지는 것보다 더욱 유용한 결과산출이 가능하게 하였다. 본 연구에서는 흰쥐의 생체내 실험모델로 하나의 바이러스 또는 이중 바이러스 주입에 PRV의 유전자 조작된 2종 바이러스를 사용하였다. 이 2종의 바이러스는 PRV의 Bartha 종에서 유래되었지만 면역조직화학적으로 검출할 수 있는 동일한 유전산물을 산출할 수 있도록 구성되었다. PRV-BaBlu는 PRV 게놈의 Us 구역 중 gC 자리에 lacZ 유전자를 삽입하여 산출되었는데 $\beta-galactosidase$ 발현은 이 바이러스에 감염된 신경원의 독특한 표시자로 나타났다. PRV-D는 2가지 단계에 의해 조성되었는데 첫째, PRV-Bartha의 Us 구역의 일부 유전자를 제거하고, 야생형인 PRV-Be DNA로 복구시켰는데 이로써 PRV-D는 PRV-Bartha 또는 PRV-Bablu에 존재하고 있지 않는 외피 당단백질인 gE와 gI를 지니게 되었다. 본 연구의 결과는 다음과 같았다. 첫째, PRV-D의 개별적 접종에 의해 얻어진 감염은 PRV-BaBlu에 의한 동일 신경회로의 감염보다 유의하게 빨랐다. 둘째, 유전자 조작된 PRV의 변이종은 변이종 상호간 및 부모 바이러스와 상이하였다. PRV-D는 PRV-Bartha 또는 PRV-BaBlu보다 감염독성이 더 강했고, PRV-BaBlu는 PRV-Bartha보다 감염독성이 약했다. 셋째, 결장을 지배하는 미주신경동쪽핵내 신경원은 변이종 바이러스들을 동시에 접종하였을 경우 이중감염을 나타내었다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.428-430
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• 2003

인유두종바이러스(human papillomavirus: HPV)는 감염되었을 때 각종 악성 종양을 유발할 수 있는 작은 DNA 바이러스이다. 고위험군에 속하는 HPV의 감염은 암으로 진행될 수 있는 가능성이 크다. 본 논문은 HPV를 분류할 수 있는 기계 학습 기법을 제안하고자 한다. 제안된 학습 기법은 단백질 서열을 효과적으로 분류할 수 있는 커널(kernel) 방법에 기반을 두고 있다. 위험군 분류는 감염의 메커니즘의 이해와 유전자칩과 같은 새로운 의학 도구의 개발 등에 있어서 중요한 정보를 제공해 줄 수 있다. 실험 결과는 중요한 부위의 탐색에 의한 커널 기반의 학습 방법이 우수한 성능을 보이는 것으로 나타났다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.309-310
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• 2003

현재 어류 질병 바이러스를 검출해내기 위해 이용되는 PCR법이나 ELIZA법 만으로는 신속성을 필요로 하는 바이러스 검출에서는 불리하다(Bruchhof et. al., 1995). 따라서 기존의 유전자 진단법을 대체할 수 있고, 동시에 수백 개 이상의 유전자를 빠른 시간 내에 검색할 수 있는 DNA chip 기술을 이용하여 넙치, 돔등의 해산어와 일부 연어과 어류에 질병을 일으키는 rhabdovirus를 신속하고 정확하게 진단할 수 있는 저밀도 oligonucleotide chip을 개발하고자 한다(Chizhikov et at., 2001). (중략)

• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.455-460
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• 1986

Dane particle was prepared from the plasma of chronic HBsAg carrier with high levels of HBsAg activity. DNA extracted front Dane particle core after a DNA polymerase reaction with $\alpha$-($^{32}$P) dNTP, was identified as HBV DNA by liquid scintillation counter and agarose gel electrophoresis-G.M. counting. To produce Hepatitis B surface antigen for use as a vaccine against Hepatitis B virus infection, yeast strains harboring recombinant plasmid with Apase promoter was used. Recombinant plasmid was construced from pHBV 130 and pAN 82, transformed into E coli, and then transferred into yeast strains. HBsAg was produced by derepression in Burkholder minimal medium with controlled inorganic phosphate concentration. The kinetics of HBsAg production was also investigated. Total HBsAg activity increased rapidly between 3 and 6 hours after transfer to phosphate-free medium and reached a maximum at around 9th hour. The transfer into phosphate-free medium after 6 hours in high phosphate cell growth medium gave maximum activity.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.1-11
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• 2021

In this review, recent foodborne outbreaks caused by viruses in the Republic of Korea (2010-2019) were analyzed. The human norovirus was found to be the major foodborne virus causing an average of 94.9% of the viral outbreaks. Reverse-transcription polymerase chain reaction (PCR) with electrophoresis has been widely used to detect viruses, but several rapid detection methods, including real-time PCR, multiplex PCR, and quantum dot assay, have also been suggested. For norovirus inactivation studies, surrogates such as murine norovirus and feline calicivirus have been widely used to identify the reduction rate owing to the limitations in laboratory cultivation. Conversely, direct cell infection studies have been conducted for other foodborne viruses such as adenovirus, astrovirus, rotavirus, and hepatitis A or E virus. Moreover, virucidal mechanisms using various physical and chemical treatments have been revealed. These recent studies suggest that rapid in situ detection and effective control are valuable for ensuring food safety against viral infections.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.2
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• pp.101-106
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• 1996

Tobacco mosaic virus (TMV) tomato strain was isolated from tomato "Seo-Kwang" in Korea. The virion was purified by density gradient centrifugation, and total viral RNA was isolated from the purified particles. Coat protein (CP) cDNA of the virus was synthesized by RT-PCR, and the purified cDNA fragment was subcloned to pBluescript II SK-. The analysis of nucleotide sequence showed that this cDNA was 693 nucleotides long from the insert of clone p1571 and p1572 which contain complete codons of the viral coat protein gene (474 nucleotides) and 3' untranslated region. The nucleotides of coat protein encoding cDNA of the strain were 6 nucleotides less than that of TMV common strain isolated from tobacco plant in Korea. The CP gene showed 70% maximum homology with that of the common strain in the nucleotide level and 86% maximum homology in amino acid level.cid level.