• 약학회지
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• 제39권5호
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• pp.560-564
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• 1995

Thirty ellagitannins originated from some Euphorbiaceous plants were tested for the inhibitory activities against AMV reverse transcriptase and replication of HIV-1 using syncytia forming assay. Most of ellagitannins showed strong inhibitory activities against AMV reverse transcriptase. Some ellagitannins including geraniin, mallotusinin, elaeocarpusin, euphorscopin and jolkianin, showed significant inhibitory activities of syncytia formation of supT1 cell line.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.278-278
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• 1994

HIV와 유사하게 retro virus의 일종인 Friend virus of Anemia strain (FVA)을 BALB/c mice 에게 감염시 reverse transcriptase 의 활성에 의해 비장의 erythroid progenitor cell 에서 증식되므로서 비장의 비대 및 빈혈을 초래하게 된다. 이를 지표로 하여 reverse transcriptase 억제작용을 지닌 항 virus 약물을 천연성분으로 부터 검색하고자 하였다. 우선, 대조약물로 사용한 기존의 항 AIDS 약물인 zidovudine (AZT) 을 FVA 가 감염된 BAB/c mice 에게 18일간 투여시 (약 100 mg/kg/day, p.o. ) 대조군에 비해 비장의 비대 및 reverse transcriptase 활성이 90% 이상 억제되었으며, 이들의 혈청을 정상 BALB/c mice 에게 재투여시에도 유사한 결과를 나타내어 reverse transcriptase 를 억제하므로서 항 virus 작용을 나타낸다는 것을 입증하였다. 그러나, 혈액중 Hemoglobin등 빈혈의 지수는 대조군과 유사한 수치를 나타내므로서 정상으로 회복되지를 못하였다. 이것은 zidovudine 자체가 지니는 골수억제에 의한 부작용 때문인 것으로 고려된다.

• 한국약용작물학회지
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• 제10권4호
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• pp.284-287
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• 2002

Four olefinic catechols, commonly referred to as urushiol were isolated from the sap of Korean Rhus verniciflua Stokes and had the stronger inhibitory effects on the reverse transcriptase of AIDS. The hexane extract with a inhibitory effects on reverse transcriptase was purified by silica and ODS gel column chromatography. The active compounds were identified by MS and $^1H-NMR$ as 3-[8' (Z), 11' (Z), 14' -pentadecatrienyl]catechol, 3-[8' (Z), 11' (Z)-pentadecadienyl]catechol, 3-[8' (Z)-penta- decenyl]catechol, and 3-pentadecylcatechol. All of these compounds showed strong inhibitory effects on reverse transcriptase of AIDS, in which 3-pentadecylcatechol exhibited the highest activity $(IC_{50}\;:\;10.87\;{\mu}g/ml)$.

• Animal cells and systems
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• 제5권3호
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• pp.195-198
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• 2001

Hepatitis B virus (HBV) polymerase, which possesses the activities of terminal binding, DNA polymerase, reverse transcriptase and RNaseH, has been shown to accomplish viral DNA replication through a pregenomic intermediate. Because the HBV polymerase has not been purified, the expression of HBV polymerase was examined in an E. coli expression system that is under the regulation of arabinose operon. The expressed individual domain containing terminal binding protein, polymerase, or RNaseH turned out to be insoluble. The activities of those domains were not able to be recovered by denaturation and renaturation using urea or guanidine-HCI. The expressed reverse transcriptase containing the polymerase and RNaseH domains became extensively degraded, whereas the proteolysis was reduced in a Ion- mutant. These results indicate that Lon protease proteolyzes the HBV reverse transcriptase expressed in E. coli.

• BMB Reports
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• 제35권2호
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• pp.248-250
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• 2002

Discrimination between the amplification of mRNA and contaminating genomic DNA is a common problem when performing a reverse transcriptase-polymerase chain reaction (RT-PCR). Even after treatment of the samples with DNAse, it is possible that negative controls (samples in which no reverse transcriptase was added) will give positive results. This indicates that there was amplification of DNA, which was not generated during the reverse transcriptase step. The possibility exists that Taq DNA polymerase acts as a reverse transcriptase, generating cDNA from RNA during the PCR step. In order to test this hypothesis, we incubated samples with a DNAse-free RNAse after the cDNA synthesis. Comparison of the results that were obtained from these samples (incubated with or without DNAse-free RNAse) confirms that the reverse transcriptase activity of Taq DNA polymerase I is a possible source of false positive results when performing RT-PCR from intronless genes. Moreover, we describe here a simple and rapid method to overcome the false positive results that originate by this activity of Taq polymerase.

• 한국동물학회지
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• 제22권4호
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• pp.141-152
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• 1979

고양이 백혈병 바이러스에서 reverse transcriptase를 분리하여 생화학적 및 면역학적 연구를 하였다. 분자량은 72,000이고, DNA polymerase와 RNase H의 활성은 0.05-1 mM $M_n^2+$와 50-80 mM KCl에서 가장 좋았다. DNA polymerase와 RNase H는 같은 단백질 분자에 있으며, chymotrypsin 처리로서 RNase H를 쪼개낼 수 있으며, 이 RNase H도 reverse transcriptase의 항체에 의해서 활성이 거의 억제 된다. Reverse transcriptase의 항체 결합위치와 활성을 내는 위치는 다른 것 같다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.81-81
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• 1993

Reverse transcriptase가 유도되는 것을 SDS-PAGE 및 효소활성 분석으로 확인할 수 있었으며 효소의 정제를 위한 예비실험으로 ammonium sulfate 및 DEAE cellulose ion exchange chromatorgraphy를 시행하였을 때 specific activity의 증가를 보여주므로서 reverse transcriptase의 분자클로닝 후 발현된 효소가 활성을 갖고 있음을 알 수 있었다. pMAL; cRI 재조합 유전자에 있는 protease의 유전자 발현을 유도했을 때 E. coli세포의 성장에 toxic하게 작용함을 관찰할 수 있었다. 이는 발현된 protease가 E. coil의 번식에 영향을 주는 것으로 믿어지며 Protease의 유전자 발현을 위한 host의 선택, inducer의 첨가시간 등 실험조건의 확립이 필요할 것으로 사료된다.

• 미생물학회지
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• 제29권1호
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• pp.34-39
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• 1991

The BTV core associated transcriptase activity, assayed by acid precipitable counts, was reduced to an undetectable level after treat the core with .$100{\mu}{\M}$ CDDP. When the RNA transcripts prepared from the CDDP treated BTV core were analysed on agaroseurea gel, it was observed that the band intensity of the large size RNA was reduced while the band intensity of the small size RNA was enhanced. Northern blot analysis showed that much of the small size RNAs appeared to be prematurely terminated transcripts. These results suggest that CDDP adduction to the template RNA blocks chain elongation process of the virion bound transcriptase that is ultimately responsible for the inactivation of BTV infectivity.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1280-1285
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• 2004

Retron is a prokaryotic genetic element, producing a short single-stranded DNA covalently linked to RNA (msDNA-RNA) by a reverse transcriptase (RT). In retron EC83, msDNA is further processed at between the 4th and the $5^{th}$ nucleotides, leaving a 79 nucleotide-long single-stranded DNA as a final product. To investigate this site-specific cleavage in msDNA synthesis, we purified the RT protein of retron EC83. Initially, RT ORF was cloned under the tac promoter, but the expression was very poor largely because of poor translation. In order to facilitate translation, the nucleotide sequence for the first nine amino acids was randomized with synonymous codons. This change of downstream sequence of translational initiation codon greatly affected the efficiency of translation. We could isolate clones which greatly increased RT production, and their sequences were compared to those of the low producers. The overproduced protein was purified and was shown to have RT activity.

• 한국동물위생학회지
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• 제22권3호
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• pp.239-245
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• 1999

The reverse transcriptase polymerase chain reaction (RT-PCR) was used for the detection of bovine coronavirus (BCV) in fecal samples by using reverse transcriptase and two primers which flanked M gene sequence of 407bp. RT-PCR detected bovine coronavirus specifically, but did not detect mouse hepatitis virus (MHV), transmissible gastroenteritis virus (TGEV), and bovine rotavirus (BRV). The M gene sequences of MHV are homologus to that of BCV, but minor differences exist in the primer regions, preventing annealing of the primers. Detection of BCV using RT-PCR was compared with ELISA and the agreement of BCV detection by RT-PCR and ELISA was 95.3%. RNA detection in positive clinical specimens was significantly better by PCR than immunological detection of BCV by ELISA.