细胞色素C在电子传递、缺氧应激和细胞凋亡的过程中起重要作用。通过人源细胞色素C和酵母细胞色素C亚铁血红素裂解酶共表达,从大肠杆菌中获得了可溶性的重组人源细胞色素C蛋白。细菌经过超声破碎后,获得的上清经350g/L硫酸铵沉淀去除杂...细胞色素C在电子传递、缺氧应激和细胞凋亡的过程中起重要作用。通过人源细胞色素C和酵母细胞色素C亚铁血红素裂解酶共表达,从大肠杆菌中获得了可溶性的重组人源细胞色素C蛋白。细菌经过超声破碎后,获得的上清经350g/L硫酸铵沉淀去除杂蛋白,再经过两次SP-Sepharose Fast Flow阳离子交换层析,获得了纯度大约为80%的人源细胞色素C。每升菌可产出10mg以上重组细胞色素C。人源细胞色素C的重组表达和纯化有助于细胞色素C功能的深入研究和应用。展开更多
AIM: To study the epitope distribution of hepatitis G virus (HGV) and to seek for the potential recombinant antigens for the development of HGV diagnostic reagents. METHODS: Fourteen clones encompassing HGV gene fragm...AIM: To study the epitope distribution of hepatitis G virus (HGV) and to seek for the potential recombinant antigens for the development of HGV diagnostic reagents. METHODS: Fourteen clones encompassing HGV gene fragments from core to NS3 and NS5 were constructed using prokaryotic expression vector pRSET and (or) pGEX, and expressed in E.coli. Western blotting and ELISA were used to detect the immunoreactivity of these recombinant proteins. RESULTS: One clone with HGV fragment from core to E1 (G1), one from E2 (G31), three from NS3 (G6, G61, G7), one from NS5B (G821) and one chimeric fragment from NS3 and NS5B (G61-821) could be expressed well and showed obvious immunoreactivity by Western blotting. One clone with HGV framment from NS5B (G82) was also well expressed, but could not show immunoreactivity by Western blotting. No obvious expression was found in the other six clones. All the expressed recombinant proteins were in inclusion body form, except the protein G61 which could be expressed in soluble form. Further purified recombinant proteins G1, G31, G61, G821 and G61-821 were detected in indirected ELISA as coating antigen respectively. Only recombinant G1 could still show immunoreactivity, and the other four recombinant proteins failed to react to the HGV antibody positive sera. Western blotting results indicated that the immunoactivity of these four recombinant proteins were lost during purification. CONCLUSION: Core to E1, E2, NS3 and NS5 fragment of HGV contain antigenic epitopes, which could be produced in prokaryotically expressed recombinant proteins. A high-yield recombinant protein (G1) located in HGV core to E1 could remain its epitope after purification, which showed the potential that G1 could be used as a coating antigen to develop an ELISA kit for HGV specific antibody diagnosis.展开更多
3'-磷酸腺苷-5'-磷酰硫酸(PAPS)是生物肝素酶法制备途径的硫磺基供体,价格高且易分解。芳基硫磺基转移酶(ASTIV,EC 2.8.2.1)可以转化对硝基硫酸苯酯(PNPS)和3'-磷酸腺苷-5'-磷酸(PAP)生成PAPS。利用大肠杆菌系统高效可...3'-磷酸腺苷-5'-磷酰硫酸(PAPS)是生物肝素酶法制备途径的硫磺基供体,价格高且易分解。芳基硫磺基转移酶(ASTIV,EC 2.8.2.1)可以转化对硝基硫酸苯酯(PNPS)和3'-磷酸腺苷-5'-磷酸(PAP)生成PAPS。利用大肠杆菌系统高效可溶性表达ASTIV。对鼠源ASTIV基因序列进行密码子优化并全合成;转入大肠杆菌BL21(DE3)中诱导表达;对表达条件进行优化,提高可溶表达量;Ni2+亲和层析纯化目标蛋白,重组ASTIV产量达到80 mg/L,纯度高达95.3%,比酶活为42.5 m U/mg;用碱性磷酸酶(CIAP)转化ASTIV构型,比酶活进一步提高到85.0 m U/mg。该研究为ASTIV重组表达,PAPS酶法制备以及生物肝素合成奠定了坚实的基础。展开更多
文摘细胞色素C在电子传递、缺氧应激和细胞凋亡的过程中起重要作用。通过人源细胞色素C和酵母细胞色素C亚铁血红素裂解酶共表达,从大肠杆菌中获得了可溶性的重组人源细胞色素C蛋白。细菌经过超声破碎后,获得的上清经350g/L硫酸铵沉淀去除杂蛋白,再经过两次SP-Sepharose Fast Flow阳离子交换层析,获得了纯度大约为80%的人源细胞色素C。每升菌可产出10mg以上重组细胞色素C。人源细胞色素C的重组表达和纯化有助于细胞色素C功能的深入研究和应用。
基金Supported by National 863 Project,No.102-07-02-079th Five-Year Sci-Tech Plan,No.96-906A-03-08
文摘AIM: To study the epitope distribution of hepatitis G virus (HGV) and to seek for the potential recombinant antigens for the development of HGV diagnostic reagents. METHODS: Fourteen clones encompassing HGV gene fragments from core to NS3 and NS5 were constructed using prokaryotic expression vector pRSET and (or) pGEX, and expressed in E.coli. Western blotting and ELISA were used to detect the immunoreactivity of these recombinant proteins. RESULTS: One clone with HGV fragment from core to E1 (G1), one from E2 (G31), three from NS3 (G6, G61, G7), one from NS5B (G821) and one chimeric fragment from NS3 and NS5B (G61-821) could be expressed well and showed obvious immunoreactivity by Western blotting. One clone with HGV framment from NS5B (G82) was also well expressed, but could not show immunoreactivity by Western blotting. No obvious expression was found in the other six clones. All the expressed recombinant proteins were in inclusion body form, except the protein G61 which could be expressed in soluble form. Further purified recombinant proteins G1, G31, G61, G821 and G61-821 were detected in indirected ELISA as coating antigen respectively. Only recombinant G1 could still show immunoreactivity, and the other four recombinant proteins failed to react to the HGV antibody positive sera. Western blotting results indicated that the immunoactivity of these four recombinant proteins were lost during purification. CONCLUSION: Core to E1, E2, NS3 and NS5 fragment of HGV contain antigenic epitopes, which could be produced in prokaryotically expressed recombinant proteins. A high-yield recombinant protein (G1) located in HGV core to E1 could remain its epitope after purification, which showed the potential that G1 could be used as a coating antigen to develop an ELISA kit for HGV specific antibody diagnosis.
文摘3'-磷酸腺苷-5'-磷酰硫酸(PAPS)是生物肝素酶法制备途径的硫磺基供体,价格高且易分解。芳基硫磺基转移酶(ASTIV,EC 2.8.2.1)可以转化对硝基硫酸苯酯(PNPS)和3'-磷酸腺苷-5'-磷酸(PAP)生成PAPS。利用大肠杆菌系统高效可溶性表达ASTIV。对鼠源ASTIV基因序列进行密码子优化并全合成;转入大肠杆菌BL21(DE3)中诱导表达;对表达条件进行优化,提高可溶表达量;Ni2+亲和层析纯化目标蛋白,重组ASTIV产量达到80 mg/L,纯度高达95.3%,比酶活为42.5 m U/mg;用碱性磷酸酶(CIAP)转化ASTIV构型,比酶活进一步提高到85.0 m U/mg。该研究为ASTIV重组表达,PAPS酶法制备以及生物肝素合成奠定了坚实的基础。
