A full-length sequence coding for △^12 fatty acid desaturase gene from peanut（Arachis hypogaea L.）was cloned into the expression vector, pRSETB, to generate recombinant plasmid pRSET/HO-A, which was subsequently tr...A full-length sequence coding for △^12 fatty acid desaturase gene from peanut（Arachis hypogaea L.）was cloned into the expression vector, pRSETB, to generate recombinant plasmid pRSET/HO-A, which was subsequently transformed into expression Escherichia. coli BL21（DE3）pLysS. The △^12 fatty acid desaturase was highly expressed in E. coli BL21（DE3）pLysS in the presence of isopropyl-D-thiogalactopyranoside （IPTG）. The fusion protein was purified and used to form a reaction system in vitro by adding oleic acid as substrate and incubating it at 20℃ for 6 h. Total fatty acids was extracted and methlesterified and then analyzed with gas chromatography. A novel peak corresponding to linoleic acid methyl ester standards was detected with the same retention time. GC-MS （gas chromatogram and gas chromatogram-mass spectrometry） analysis showed that the novel peak was linoleic acid methyl ester. These results exhibited △^12 fatty acid desaturase activity, which could convert oleic acid to linoleic acid specifically.展开更多
Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ...Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ( L.) Pall aerial tissue. Sscat1 (1.7 kb) contains a full open reading frame of 492 amino acids and Sscat2 (1.1 kb) is a partial clone. BLAST analysis indicates that the two clones share 71.9% identity in nucleotide sequence and 75% identity in deduced amino acid sequence within the last 287 amino acid residues of Sscat1. Southern blotting analysis showed that Sscat1 is multicopy in S. salsa genome, while Sscat2 is a single copy gene. Northern blotting analysis showed a rapid increase in the steady-level of both genes in roots after 48 It salt treatment, but only Sscat1 was induced in salinity treated leaves. Time-course analysis carried out in leaves confirmed that Sscat1 was induced by salt stress, in contrast to Sscat2. These implied that the expression of Sscat1 and Sscat2 genes are differentially regulated in S. salsa. The activity of total catalase is dramatically increased in response to salt stress.展开更多
目的探究重组表达醛脱氢酶8A1(ALDH8A1)在胃癌组织中的表达情况及与临床病理参数的关系,并分析其对患者远期预后的影响。方法纳入2012年3月—2018年4月在蚌埠医科大学第一附属医院接受根治术治疗的109例胃癌患者,采用免疫组化法分析ALDH...目的探究重组表达醛脱氢酶8A1(ALDH8A1)在胃癌组织中的表达情况及与临床病理参数的关系,并分析其对患者远期预后的影响。方法纳入2012年3月—2018年4月在蚌埠医科大学第一附属医院接受根治术治疗的109例胃癌患者,采用免疫组化法分析ALDH8A1在胃癌及癌旁组织的表达情况,并运用统计学方法分析其与临床病理特征的关系;采用Kaplan-Meier曲线分析ALDH8A1的表达对胃癌患者术后5年生存率的影响。结果ALDH8A1在胃癌组织中的表达明显高于癌旁组织(P<0.001)。CEA≥5μg/L、CA19-9≥37 kU/L、癌细胞类型为腺癌、T3~4期及N2~3期患者ALDH8A1表达水平更高(P<0.05)。Kaplan-Meier曲线分析及多因素分析显示ALDH8A1高表达(HR=2.674,95%CI:1.293~5.533,P=0.008)可能会增加胃癌患者术后的死亡率。ROC曲线表明以2.555为截点值,ALDH8A1对胃癌患者预后具有较高的预判价值(灵敏度为68.97%,特异度为86.27%)。GO和KEGG富集分析显示ALDH8A1与细胞减数分裂、DNA结合和细胞周期等信号通路有关。结论ALDH 8 A 1在胃癌组织中高表达并促进胃癌的恶性进展,与预后不良相关。展开更多
The mature Shiga toxin B （StxB） gene was optimized and generated by overlapping PCR. Recombinant expression vector pQE40-DHFR/StxB was constructed when the gene was cloned into pQE fusion expression vector. Induced ...The mature Shiga toxin B （StxB） gene was optimized and generated by overlapping PCR. Recombinant expression vector pQE40-DHFR/StxB was constructed when the gene was cloned into pQE fusion expression vector. Induced by Isopropyl β-D-thiogalactoside （IPTG）, the DHFR/StxB fusion protein was highly expressed to the level of 41.36% in E. coli MI5 cells. The 35 kDa fusion protein with a 6 His-tag was one-step purified from inclusion bodies using Ni-NTA affinity chromatography column under denaturing conditions, and was refolded by dialyzing with a decreasing urea gradient. Purified DHFR/StxB fusion protein was used to immunize Kunming mice for generating the ascitic polyclonal antibody against recombinant StxB protein by injecting sarcoma 180 cells and the titer ofascitic polyclonal antibody is up to 1： 1× 10^6 detected by the indirect enzyme linked immunosorbent assy （ELISA）. Western immunoblotting analysis revealed that the ascitic polyclonal antibody against StxB had a specific affinity for a 70 kDa shiga toxin protein of Shigella dysenteriae type 1. It is a new simple and quick method to produce a large amount of ascitic polyclonal antibody. The antibody is used to develop immunological method for detecting shiga toxin.展开更多
基金This work was supported by Chinese National Programs for High Technology Research and Development (No. 2002AA207004).
文摘A full-length sequence coding for △^12 fatty acid desaturase gene from peanut（Arachis hypogaea L.）was cloned into the expression vector, pRSETB, to generate recombinant plasmid pRSET/HO-A, which was subsequently transformed into expression Escherichia. coli BL21（DE3）pLysS. The △^12 fatty acid desaturase was highly expressed in E. coli BL21（DE3）pLysS in the presence of isopropyl-D-thiogalactopyranoside （IPTG）. The fusion protein was purified and used to form a reaction system in vitro by adding oleic acid as substrate and incubating it at 20℃ for 6 h. Total fatty acids was extracted and methlesterified and then analyzed with gas chromatography. A novel peak corresponding to linoleic acid methyl ester standards was detected with the same retention time. GC-MS （gas chromatogram and gas chromatogram-mass spectrometry） analysis showed that the novel peak was linoleic acid methyl ester. These results exhibited △^12 fatty acid desaturase activity, which could convert oleic acid to linoleic acid specifically.
文摘Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ( L.) Pall aerial tissue. Sscat1 (1.7 kb) contains a full open reading frame of 492 amino acids and Sscat2 (1.1 kb) is a partial clone. BLAST analysis indicates that the two clones share 71.9% identity in nucleotide sequence and 75% identity in deduced amino acid sequence within the last 287 amino acid residues of Sscat1. Southern blotting analysis showed that Sscat1 is multicopy in S. salsa genome, while Sscat2 is a single copy gene. Northern blotting analysis showed a rapid increase in the steady-level of both genes in roots after 48 It salt treatment, but only Sscat1 was induced in salinity treated leaves. Time-course analysis carried out in leaves confirmed that Sscat1 was induced by salt stress, in contrast to Sscat2. These implied that the expression of Sscat1 and Sscat2 genes are differentially regulated in S. salsa. The activity of total catalase is dramatically increased in response to salt stress.
文摘目的探究重组表达醛脱氢酶8A1(ALDH8A1)在胃癌组织中的表达情况及与临床病理参数的关系,并分析其对患者远期预后的影响。方法纳入2012年3月—2018年4月在蚌埠医科大学第一附属医院接受根治术治疗的109例胃癌患者,采用免疫组化法分析ALDH8A1在胃癌及癌旁组织的表达情况,并运用统计学方法分析其与临床病理特征的关系;采用Kaplan-Meier曲线分析ALDH8A1的表达对胃癌患者术后5年生存率的影响。结果ALDH8A1在胃癌组织中的表达明显高于癌旁组织(P<0.001)。CEA≥5μg/L、CA19-9≥37 kU/L、癌细胞类型为腺癌、T3~4期及N2~3期患者ALDH8A1表达水平更高(P<0.05)。Kaplan-Meier曲线分析及多因素分析显示ALDH8A1高表达(HR=2.674,95%CI:1.293~5.533,P=0.008)可能会增加胃癌患者术后的死亡率。ROC曲线表明以2.555为截点值,ALDH8A1对胃癌患者预后具有较高的预判价值(灵敏度为68.97%,特异度为86.27%)。GO和KEGG富集分析显示ALDH8A1与细胞减数分裂、DNA结合和细胞周期等信号通路有关。结论ALDH 8 A 1在胃癌组织中高表达并促进胃癌的恶性进展,与预后不良相关。
文摘The mature Shiga toxin B （StxB） gene was optimized and generated by overlapping PCR. Recombinant expression vector pQE40-DHFR/StxB was constructed when the gene was cloned into pQE fusion expression vector. Induced by Isopropyl β-D-thiogalactoside （IPTG）, the DHFR/StxB fusion protein was highly expressed to the level of 41.36% in E. coli MI5 cells. The 35 kDa fusion protein with a 6 His-tag was one-step purified from inclusion bodies using Ni-NTA affinity chromatography column under denaturing conditions, and was refolded by dialyzing with a decreasing urea gradient. Purified DHFR/StxB fusion protein was used to immunize Kunming mice for generating the ascitic polyclonal antibody against recombinant StxB protein by injecting sarcoma 180 cells and the titer ofascitic polyclonal antibody is up to 1： 1× 10^6 detected by the indirect enzyme linked immunosorbent assy （ELISA）. Western immunoblotting analysis revealed that the ascitic polyclonal antibody against StxB had a specific affinity for a 70 kDa shiga toxin protein of Shigella dysenteriae type 1. It is a new simple and quick method to produce a large amount of ascitic polyclonal antibody. The antibody is used to develop immunological method for detecting shiga toxin.
