• 제목/요약/키워드: integrase

검색결과 63건 처리시간 0.03초

인간 포미바이러스 인테그라제 돌연변이의 특성 (Characterization of Human Foamy Virus Integrase Mutant)

  • 강승이;오수아;이학성;한성태;신차균
    • 약학회지
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    • 제49권3호
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    • pp.198-204
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    • 2005
  • Human foamy virus (HFV) integrase mediates integration of viral c-DNA into cellular DNA. In this process, HFV integrase recognizes its own viral DNA specifically and catalyzes insertion of viral c-DNA. In order to study catalytic domains and residues, three deletion mutants and two point mutants of HFV integrase were constructed and analyzed with respect to enzymatic activities. The C-terminal deletion mutant showed decreased enzymatic activities while the N-terminal deletion mutant lost the activities completely, indicating that the N-terminal domain is more important than the C-terminal domain in enzymatic reaction. The point mutants, in which an aspartic acid at the 164th position or a glutamic acid at the 200th position of the HFV integrase protein was changed to an alanine, lost the enzymatic activities completely. However, they were well complemented with other defective deletion mutants to recover enzymatic activities partially. Therefore, these results suggest that the aspartic acid and glutamic acid at the respective 164th and 200th positions are catalytic residues for enzymatic reaction.

Multiple Functions of the Amino-terminal Domain of Bacteriophage Lambda Integrase: A New Member of Three-stranded $\beta-sheet$ DNA-binding Proteins

  • Cho Eun Hee
    • 한국미생물학회:학술대회논문집
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    • 한국미생물학회 2002년도 추계학술대회
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    • pp.159-161
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    • 2002
  • Bacteriophage lambda integrase carries out the site-specific recombination of lambda. Integrase contains two DNA binding domains with distinct sequence specificity, namely arm-type binding and core-type binding domains. The amino-terminal arm-binding domain is structurally related to the three-stranded $\beta-sheet$ family of DNA-binding domains. Integrase binding to the high affinity arm-type site by the amino-terminal domain facilitates Int binding to the low affinity core-type site, where the cleavage and strand exchange occurs. The amino-terminal domain of Int also modulates the core-binding and catalysis through intramolecular domain-domain interaction and/or intermolecular interactions between Int monomers. In addition, the amino-terminal domain interacts cooperatively with excisionase during excision. This indicates that amino-terminal domain of Int plays an important role in formation of proper higher-order nucleoprotein structure required for lambda site-specific recombination.

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Phenotypes of Integrase-Mutated Human Immunodeficiency Virus Type-1(HIV-1)

  • 신차균
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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    • pp.92-92
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    • 1993
  • Point mutations in a highly conserved central region of the HIV-1 integrase protein were analyzed for their effects on viral replication and virion morphogenesis. Conservative amino acid replacements of two amino acid residues invariant un retroviral integrases, D116 and E152 of HIV-1, as well as the highly conserved amino acid S147, completely blocked viral replication in two CD4$\^$+/ human T cell lines. Mutation of four other highly conserved amino acids in the region had no detectable effect on viral replication, while Mutations at two positions, N117 and Y143, resulted in viruses with a delayed replication phenotype. Characteristic and reproducible defects id virion core structure were observed by electron microscopic analysis of sore of the replication defective integrase point mutants, indicating that mutant integrase proteins can interfere with the process of virion core maturation.

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동물 세포 내에서 MJ1 인티그라제에 의한 부위 특이적 재조합 (Site-Specific Recombination by the Integrase MJ1 on Mammalian Cell)

  • 김혜영;윤보현;장효일
    • 한국미생물·생명공학회지
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    • 제39권4호
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    • pp.337-344
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    • 2011
  • 이전 연구에서, bacteriophage ${\Phi}FC1$이 Enterococcus faecalis KBL703에서 UV induction을 통해 분리 동정되었으며, ${\Phi}FC1$은 phage attachment site인 attP와 bacterial attachment site인 attB 사이에서 site-specific integration을 촉매하는 integrase를 가지고 있다는 것을 밝혀냈으며 이를 MJ1이라 명명하였다. 이 연구에서는 이를 바탕으로 MJ1에 의한 site-specific integration의 효율을 Escherichia coli와 NIH3T3 cell에서 확인 하기 위해 attP, attB, MJ1을 각각의 벡터에 삽입하였다. MJ1 인테그라제에 의한 재조합을 수행하기 위해서 기질 벡터 pABLP를 $DH5{\alpha}$에 형질전환시킨 후, LB 배지에서 $37^{\circ}C$ 1시간 배양한 후 암피실린(ampicillin)과 테트라싸이클린(tetracycline) 항생제 플레이트로 pGMJ1과 pABLP 같이 가지고 있는 colony 들을 선별하여, LacZ 유전자가 불활성화 된 흰색 콜로니 개수를 세고 통계를 낸 결과 integration의 frequency가 99% 이상인 것으로 나타났다. 또한, 실제로 재조합이 일어났는 지를 확인하기 위해서 콜로니 PCR을 수행하여 재조합의 산물인 attL 150 bp을 확인하였다. PCR 산물은 염기서열분석을 통해 정확한 site-specific integration이 일어났음을 확인하였다. MJ1에 의한 integration을 보이기 위해 attP와 attB를 가지고 있는 vector를 MJ1 expression vector와 함께 NIH3T3 cell에 cotransfection 했으며 GFP를 reporter로 사용해 그 activity를 관찰하였다. NIH3T3 cell에서 GFP의 발현을 형광 현미경을 통해 알아본 결과, MJ1에 의한 sitespecific integration이 다른 accessory protein의 도움 없이 일어난다는 것을 볼 수 있었다. 마찬가지 방법으로, attR과 attL 간의 excision을 GFP로 알아본 결과, GFP는 발현하지 않았으며, 이는 MJ1에 의한 excision이 일어나지 않았음을 보여주었다. 이와 같은 결과로 볼 때, MJ1의 host만이 아니라 넓은 범위안에서도 integration을 수행할 수 있다는 것을 보여주었다. 따라서 MJ1을 이용한 site-specific integration system의 개발은 gene therapy를 위한 gene delivery system의 구축에 있어서 좋은 시작이 될 수 있다.

Explorations of the Electrostatic Character of a Model of Human Immunodeficiency Virus Type 1 Integrase to Offer a Prediction for the Orientation and Nature of DNA binding

  • Jung, Eun-Sun;Kwon, Yong-Jung
    • 산업기술연구
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    • 제26권B호
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    • pp.163-171
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    • 2006
  • Human immunodeficiency virus type 1 (HIV-1) integrase plays a critical role in the life cycle of the HIV virus. An ability to accurately map its electrostatic potential, and then use this information to predict the manner in which DNA will bind to the active site of the catalytic domain could provide a foundation for inhibitory design. Attempts to discern the crystal structure of HIV-1 integrase have proven problematic, especially in the region of enzymatic activity, that being those residues involved in the catalysis of the integration of viral DNA into the host cell. However, there is a structural correlation in to the region of interest with avian sarcoma virus (ASV), so a homology model utilizing this similarity was constructed to approximate the behavior/structure of the undetermined portions of the HIV-1 integrase crystal. After this model was constructed and its energy minimized, electrostatic calculations were carried out on the substance, so that an electrostatic potential map was constructed. Using this information, it was determined that DNA binding was oriented so as to exploit the regions of positive potential nearby the active site, as well as the positive potential of the magnesium cofactors.

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HIV/AIDS Management: Dolutegravir Based Antiretroviral Drug Therapy

  • John, Ikpeama Osita;Emmanuel, Okoh Emeka;Anthonia, Ikpeama Chizoba;Joy, Ikpeama Chinwe;Adimabua, Okafor Patrick;Osazuwa, Igbineweka Osa;Andrew, Ikpeama Emeka;Mariam, Onuzulike Nonye;Gami, Hilary Tumba
    • 식품보건융합연구
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    • 제6권4호
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    • pp.17-19
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    • 2020
  • HIV/AIDS disease still remain a global pandemic and it's management has undergone series of treatment changes and improvement although there is still no permanent cure.Dolutegravir belongs to a group of HIV drugs called integrase inhibitors. Integrase inhibitors block an HIV enzyme called integrase. By blocking integrase, integrase inhibitors prevent HIV from multiplying and can reduce the amount of HIV in the body.Dolutegravir combination based regimen has turned out to be very effective (antiviral) with negligible rare side effects on clients. This drug (Dolutegravir based regimen) combination has successfully increased the appetite for food of all the clients, unlike others and has shown to reduce viral load in the most shortest period ever. It can be deduced that development of resistant mutant virus will be reduced if not eliminated with dolutogravir based regimen.The role of Continuous adherence counseling has shown to improve clients treatment management. It is important to note that the availability of food has direct effect on the economic status or financial weight on the client. Hence the progress that is increase in body mass index (BMI) is a direct impact of the availability of food for the clients.

Biochemical characteristics of functional domains using feline foamy virus integrase mutants

  • Yoo, Gwi-Woong;Shin, Cha-Gyun
    • BMB Reports
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    • 제46권1호
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    • pp.53-58
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    • 2013
  • We constructed deletion mutants and seven point mutants by polymerase chain reaction to investigate the specificity of feline foamy virus integrase functional domains. Complementation reactions were performed for three enzymatic activities such as 3'-end processing, strand transfer, and disintegration. The complementation reactions with deletion mutants showed several activities for 3'-end processing and strand transfer. The conserved central domain and the combination of the N-terminal or C-terminal domains increased disintegration activity significantly. In the complementation reactions between deletion and point mutants, the combination between D107V and deletion mutants revealed 3'-end processing activities, but the combination with others did not have any activity, including strand transfer activities. Disintegration activity increased evenly, except the combination with glutamic acid 200. These results suggest that an intact central domain mediates enzymatic activities but fails to show these activities in the absence of the N-terminal or C-terminal domains.

Characterization of Ty3-gypsy-like Elements in Hibiscus syriacus

  • Jeung, Ji-Ung;Cho, Sung Ki;Lee, Seung Jae;Shin, Jeong Sheop
    • Molecules and Cells
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    • 제19권3호
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    • pp.318-327
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    • 2005
  • Southern blot analysis revealed a ubiquitous distribution and high copy number of Ty3-gypsy-like elements in the genome of Hibiscus syriacus. Comparative phylogenetic analysis of the large subunit of Rubisco and the integrase region of Ty3-gypsy elements in various plant species indicated that the retrotransposon-like sequences have different evolutionary histories and their own unique polymorphism in the H. syriacus population. Sequence-tagged site-restriction fragment length polymorphisms (STS-RFLP) analysis also indicated great variability in the numbers and sequences of Ty3-gypsy-like elements within H. syriacus varieties. Ty3-gypsy-like elements may still be active within H. syriacus, since Northern analysis of wounded leaves of H. syriacus variety Saehan with a probe for the integrase domain gave strong hybridization signals. The sequence heterogeneity and ubiquity of the Ty3-gypsy-like elements in H. syriacus genomes could provide reliable DNA markers for line identification as well for the analysis of genetic diversity in H. syriacus.

합성 기질에 의해 형성된 Lambda Site-specific Recombination 중간 대사물의 분석 (Analysis of Lambda Site-specific Recombination Inermediates Generated by Synthetic Substrates)

  • 이나영;유승구
    • 한국미생물·생명공학회지
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    • 제23권3호
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    • pp.282-287
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    • 1995
  • Integrase (Int) carries out the cutting and resealing of attachment (att) site DNA via a covalent Int-DNA intermediate. A family of synthetic substrate DNAs was designed to accumulate Int-DNA intermediate. Int-DNA intermediates accumulated by half substrate was analyzed by SDS- KCI precipitation and restriction digestion. The results showed that Int-half DNA intermediate was circular and contained covalently bound Int molecule. Int-DNA intermediates were also trapped with three other kinds of synthetic substrates.

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