• Natural Product Sciences
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• v.4 no.4
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• pp.241-244
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• 1998

For the development of anti-AIDS agents, thirty-seven methanol extracts of Korean plant materials were tested for their inhibitory effects on human immunodeficiency virus type-1 (HIV-1) protease. Extracts of seven plants showed more than 30% inhibitory activities on HIV-1 protease at a concentration of $100\;{\mu}g/ml$. The bark of Berchemia berchemiaefolia, the leaf of Lindera erythrocarpa and the whole plant of Siegesbeckia pubescens exhibited significant inhibititory activities on HIV-1 protease with 56.2, 50.8, and 46.6%, respectively.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.4 no.1
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• pp.199-209
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• 1998

In order to find antiviral effect against Human immunodeficiency virus(HIV), Herpes simplex virus type I(HSV-1) and II(HSV-2) from herb medicines, publicated 29 paters on anti-viral effect of herbal medicines and a convenient virus-induced cytopathic effect (CEP) inhibition assay was introduced. The major virus on experiment are HIV, Hepatitis B virus and HSV-1,2. Those of other studies showed inhibition of infected virus DNA replication and screening test of herbal medicines. More than 15 extractions were prepared by pure water boiling from herbal medicines, and their toxicity of infected cell and anti-viral activities were evaluated. Among them, the major part of herbal medicines showed cell stability compared with the contrast. Cytotoxic concentration (CC) of the $H_2O$ extracts of Padoo against HIV was <4.0, Hyungbangpaedoksan against HIV was 9.3, Whangyonhaedoktang against HIV-1 and HSV-2 was 15.3. These are high level cytotoxic concentration compared with the contrast. But antiviral effect was unable to figure out for selective $index(SI)=CC_{50}/EC_{50}$. The other herbal medicines were unable to showed potent anti-HIV and anti-HSV activity. The antiviral activation using herbs in this thesis have unlimited objects, to select research object will help to show the direction of antiviral drug development that have less side effect and more excellent efficiency.

• Korean Journal of Microbiology
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• v.29 no.1
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• pp.1-7
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• 1991

Human immunodeficiency virus type 1 (HIV-1) causes a deadly infectious disease, Acquired Immunodeficiency Syndrome (ADIS). As a first step to develop a reliable and fast diagnostic procedure for HIV-1 infection, we cloned various immunodominant epitopes of HIV-1 in bacterial expression vectors containing tac or trp promoter. While the protein level of direct expression of gp160 was low, trp E fused gp120, gp41 and p17-p24 were produced at high levels (15-30% of total bacterial proteins) in E. coli. Since gp120 and gp41 contain relatively conserved regions which can react with antibodies in the plasma from most of HIV-1 infected individuals, these expression clones were used for large preparations of HIV-1 antigens.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.111-115
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• 1995

Natural products, total number of 175, were screened to test for their effect on the replication of human immunodeficiency virus type 1 (HIV-1). Five of them, such as Eriobotrya japonica, Eugenia caryphyllata, Cuscuta chinensis, Glycyrrhiza uralensis, and Coptis chinensis were shown to be effective in inhibiting the replication of HIV-1 in tissue culture and their selectivity indexes were 42, 40, 14, 18 and 65, respectively. To further fractionate Coptis chinensis, which is shown to be highest anti-HIV-1 activity, methanol extracts of Coptis chinensis were fractionated into methylene chloride at pH3, pH10 and water residue. The selectivity Indexes of CH$_2$C1$_2$(pH 3), CH$_2$C1$_2$(pH 10) and water residue were 50, 22 and 98 respectively. Our results show that the water residue of Coptis chinensis was the most effective for anti-HIV-1 activity.

• Proceedings of the Microbiological Society of Korea Conference
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• 1998.04a
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• pp.42.1-42.1
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• 1998

• IMMUNE NETWORK
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• v.2 no.3
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• pp.150-157
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• 2002

Background: Although Tat plays a role as a potent transactivator in the viral gene expression from the Human Immunodeficiency Virus type 1 long terminal repeat (HIV-1 LTR), it does not function efficiently in rodent cells implying the absence of a human specific factor essential for Tat-medicated transactivation in rodent cells. In previous experiments, we demonstrated that one of chimeric forms of TAR (transacting responsive element) of HIV-1 LTR compensated the restriction in rodent cells. Methods: To characterize the nature of the compensation, we tested the effects of several upstream binding factors of HIV-1 LTR by simple substitution, and also examined the role of the configuration of the upstream binding factor(s) indirectly by constructing spacing mutants that contained insertions between Sp1 and TATA box on Tat-mediated transactivation. Results: Human Sp1 had no effect whereas its associated factors displayed differential effects in human and rodent cells. In addition, none of the spacing mutants tested overcame the restriction in rodent cells. Rather, when the secondary structure of the chimeric HIV-1 TAR construct was destroyed, the compensation in rodent cells was disappeared. Interestingly, the proper interaction between Sp1 and TATA box binding proteins, which is essential for Tat-dependent transcription, was dispensable in rodent cells. Conclusion: This result suggests that the human-specific Tat cofactor acts to allow Tat to interact effectively in a ribonucleoprotein complex that includes Tat, cellular factors, and TAR RNA, rather than be associated with the HIV-1 LTR upstream DNA binding factors.

• Journal of Industrial Technology
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• v.26 no.B
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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.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.1
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• pp.25-30
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• 2001

Viral safety is a prerequisite for manufacturing clinical albumin and immunoglobulins from human plasma pools. This study was designed to evaluate the efficacy of cold ethanol fractionation and pasteurization (60$\^{C}$ heat treatment for 10h) for the removal/inactivation of human immunodeficiency virus type 1 (HIV-1) during the manufacturing of albumin and immunoglobulins. Samples from the relevant stages of the production process were spiked with HIV-1, and the amount of virus in each fraction was quantified by the 50% tissue culture infectious dose(TCID(sub)50). Both fraction IV fractionation and pasteurization steps during albumin processing were robust and effective in inactivating HIV-1, titers of which were reduced from an initial 8.5 log(sub)10 TCID(sub)50 to undetectable levels. The log reduction factors achieved were $\geq$ 4.5 and $\geq$ 6.5, respectively. In addition, fraction III fractionation and pasteurization during immunoglobulins processing were robust and effective in eliminating HIV-1. HIV-1 titers were reduced from an initial 7.3 log(sub)10 TCID(sub)50 to undetectable levels. The log reduction factors achieved in this case were $\geq$ 4.9 and $\geq$ 5.3, respectively. These results indicate that the process investigated for the production of albumin and immunoglobulins have sufficient HIV-1 reducing capacity to achieve a high margin of safety.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.15-15
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• 2005

• Biomolecules & Therapeutics
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• v.2 no.2
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• pp.155-160
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• 1994

Human immunodeficiency virus type 1 (HIV-1) protease is essential for the replication of the virus and it is therefore an attractive target for antiviral drugs of HIV-1. Several dipeptide isosteres containing 2-isoxazoline or $\alpha$-hydroxy ketomethylene have been synthesized and their inhibitory effects on the HIV-1 protease examined. The enzymatically active HIV-1 protease was purified to homogeniety from E. coli transformed with a recombinant plasmid (pMAL-pro) containing the entire gene encoding the protease. The purified protease had the substrate specificity with Km value of 9.8$\mu$M when an undecapeptide His-Lys-Ala-Arg-Val-Leu-(p-nitro)Phe-Glu-Ala-Nle-Ser-amide was used as a substrate, and the products from the substrate after specific cleavage by HIV-1 protease were analyzed by HPLC. The synthetic compounds containing dipeptide isosteres showed specific inhibitory effects while a dipeptide isostere containing an isoxazoline ring inhibited the HIV-1 protease competitively with Ki value of 500 $\mu$M. Even if the inhibition effects of HIV-1 protease were not very high, these novel dipeptide isosteres can be used as key structural moieties for developing specific inhibitors of HIV-1 protease.