从口蹄疫病毒(foot-and-m ou th d isease v irus,FM DV)细胞培养物中提取总RNA,经一步法RT-PCR获得了长约230 bp的3B基因片段,将PCR产物连接到pM D-18T载体上并测序,用B amHⅠ与H indⅢ双酶切后,将3B基因融合到pGEX-KG载体上形成表达质...从口蹄疫病毒(foot-and-m ou th d isease v irus,FM DV)细胞培养物中提取总RNA,经一步法RT-PCR获得了长约230 bp的3B基因片段,将PCR产物连接到pM D-18T载体上并测序,用B amHⅠ与H indⅢ双酶切后,将3B基因融合到pGEX-KG载体上形成表达质粒pGEX-KG-3B,转化到BL 21(DE 3)中在27℃诱导表达,将表达产物进行SDS-PAGE和蛋白质斑点EL ISA。结果表明3B基因主要以可溶形式高效表达,表达产物具有免疫原性。以纯化的表达产物为抗原建立了间接酶联免疫吸附试验(I-EL ISA)。方阵滴定其最佳包被浓度是6.1μg/孔,最佳血清稀释倍数为1∶80,通过测定36份FM DV阴性血清,确定了该方法的阳性判定标准。结果表明,该方法特异性强、重复性好;用3B-EL ISA方法与美国联合生物医学公司(U B I)生产的合成肽检测试剂盒U B I○RFM DV N S-EL ISA对比检测44份血清样品,符合率为93.1%。证明3B-EL ISA方法可用于口蹄疫的鉴别诊断。展开更多
BACKGROUND Hepatitis C virus genotype 3a(HCV G3a)is highly prevalent in Pakistan.Due to the elevated cost of available Food and Drug Administration-approved drugs against HCV,medicinal natural products of potent antiv...BACKGROUND Hepatitis C virus genotype 3a(HCV G3a)is highly prevalent in Pakistan.Due to the elevated cost of available Food and Drug Administration-approved drugs against HCV,medicinal natural products of potent antiviral activity should be screened for the cost-effective treatment of the disease.Furthermore,from natural products,active compounds against vital HCV proteins like non-structural protein 3(NS3)protease could be identified to prevent viral proliferation in the host.AIM To develop cost-effective HCV genotype 3a NS3 protease inhibitors from citrus fruit extracts.METHODS Full-length NS3 without co-factor non-structural protein 4A(NS4A)and codon optimized NS3 protease in fusion with NS4A were expressed in Escherichia coli.The expressed protein was purified by metal ion affinity chromatography and gel filtration.Citrus fruit extracts were screened using fluorescence resonance energy transfer(FRET)assay against the protease and polyphenols were identified as potential inhibitors using electrospray ionization-mass spectrometry(MS)/MS technique.Among different polyphenols,highly potent compounds were screened using molecular modeling approaches and consequently the most active compound was further evaluated against HCV NS4A-NS3 protease domain using FRET assay.RESULTS NS4A fused with NS3 protease domain gene was overexpressed and the purified protein yield was high in comparison to the lower yield of the full-length NS3 protein.Furthermore,in enzyme kinetic studies,NS4A fused with NS3 protease proved to be functionally active compared to full-length NS3.So it was concluded that co-factor NS4A fusion is essential for the purification of functionally active protease.FRET assay was developed and validated by the half maximal inhibitory concentration(IC50)values of commercially available inhibitors.Screening of citrus fruit extracts against the native purified fused NS4A-NS3 protease domain showed that the grapefruit mesocarp extract exhibits the highest percentage inhibition 91%of protease activity.Among the com展开更多
Retraction note:Khan M,Rauf W,Habib F,Rahman M,Iqbal M.Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonan...Retraction note:Khan M,Rauf W,Habib F,Rahman M,Iqbal M.Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonance energy transfer assay and mass spectrometry.World J Hepatol 2020;12(11):976-992 PMID:33312423 DOI:10.4254/wjh.v12.i11.976.The online version of the original article can be found at https://www.wjgnet.com/1948-5182/full/v12/i11/976.htm.展开更多
文摘从口蹄疫病毒(foot-and-m ou th d isease v irus,FM DV)细胞培养物中提取总RNA,经一步法RT-PCR获得了长约230 bp的3B基因片段,将PCR产物连接到pM D-18T载体上并测序,用B amHⅠ与H indⅢ双酶切后,将3B基因融合到pGEX-KG载体上形成表达质粒pGEX-KG-3B,转化到BL 21(DE 3)中在27℃诱导表达,将表达产物进行SDS-PAGE和蛋白质斑点EL ISA。结果表明3B基因主要以可溶形式高效表达,表达产物具有免疫原性。以纯化的表达产物为抗原建立了间接酶联免疫吸附试验(I-EL ISA)。方阵滴定其最佳包被浓度是6.1μg/孔,最佳血清稀释倍数为1∶80,通过测定36份FM DV阴性血清,确定了该方法的阳性判定标准。结果表明,该方法特异性强、重复性好;用3B-EL ISA方法与美国联合生物医学公司(U B I)生产的合成肽检测试剂盒U B I○RFM DV N S-EL ISA对比检测44份血清样品,符合率为93.1%。证明3B-EL ISA方法可用于口蹄疫的鉴别诊断。
文摘BACKGROUND Hepatitis C virus genotype 3a(HCV G3a)is highly prevalent in Pakistan.Due to the elevated cost of available Food and Drug Administration-approved drugs against HCV,medicinal natural products of potent antiviral activity should be screened for the cost-effective treatment of the disease.Furthermore,from natural products,active compounds against vital HCV proteins like non-structural protein 3(NS3)protease could be identified to prevent viral proliferation in the host.AIM To develop cost-effective HCV genotype 3a NS3 protease inhibitors from citrus fruit extracts.METHODS Full-length NS3 without co-factor non-structural protein 4A(NS4A)and codon optimized NS3 protease in fusion with NS4A were expressed in Escherichia coli.The expressed protein was purified by metal ion affinity chromatography and gel filtration.Citrus fruit extracts were screened using fluorescence resonance energy transfer(FRET)assay against the protease and polyphenols were identified as potential inhibitors using electrospray ionization-mass spectrometry(MS)/MS technique.Among different polyphenols,highly potent compounds were screened using molecular modeling approaches and consequently the most active compound was further evaluated against HCV NS4A-NS3 protease domain using FRET assay.RESULTS NS4A fused with NS3 protease domain gene was overexpressed and the purified protein yield was high in comparison to the lower yield of the full-length NS3 protein.Furthermore,in enzyme kinetic studies,NS4A fused with NS3 protease proved to be functionally active compared to full-length NS3.So it was concluded that co-factor NS4A fusion is essential for the purification of functionally active protease.FRET assay was developed and validated by the half maximal inhibitory concentration(IC50)values of commercially available inhibitors.Screening of citrus fruit extracts against the native purified fused NS4A-NS3 protease domain showed that the grapefruit mesocarp extract exhibits the highest percentage inhibition 91%of protease activity.Among the com
文摘Retraction note:Khan M,Rauf W,Habib F,Rahman M,Iqbal M.Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonance energy transfer assay and mass spectrometry.World J Hepatol 2020;12(11):976-992 PMID:33312423 DOI:10.4254/wjh.v12.i11.976.The online version of the original article can be found at https://www.wjgnet.com/1948-5182/full/v12/i11/976.htm.
