恐龙遗址旅游指南(3)欧洲篇(中B)

第三站:英国西德纳姆镇(Sydenhm)水晶宫公园(Crystal Palace Park) 离开刘易斯镇,我们原路返回伦敦市,继续这次朝圣之旅.我们先到著名的伦敦桥南端的伦敦桥站火车站(London Bridge),这个车站于1836年12月开始运营,以连结东南郊的通勤及短程列车为主,因此车站的早晚高峰时间极为拥挤混杂.     

中国人补体第3成份(C3)和备解素因子B(Bf)的遗传多态性

使用琼脂糖凝胶电泳和免疫结合琼脂糖凝胶电泳方法分别调查了补体第3成份(C3)和备解素因子B(Bf)在中国人中的多态性。在388名无关个体中,有两种常见的C3表现型SS和FS,基因频率为C3~F=0.0039,C3~S=0.9961。未发现稀少的C3变异型。在200例无关个体中,Bf表现型为S155人,FS 38人,F 6人以及1例FS0.7。基因频率为Bf~s=0.8700,Bf~F=0.1275,Bf~(S0.7)=0.0025。C3和Bf表现型分布与Hardy-Weinberg平衡相一致。     

阿扎霉素B(Azalomycin B)研究进展

介绍阿扎霉素B的生物学来源,研究历史,主要理化性质和结构确定,同时阐述了阿扎霉素B的生物合成途径,构效关系,生物学特性和应用前景。     

棉铃虫细胞色素P450 337B3(CYP337B3)的表达、纯化及结晶

【目的】以抗性棉铃虫Helicoverpa armigera体内发现的一种基因重组导致的嵌合型P450酶CYP337B3作为研究对象,通过基因克隆、体外重组表达、蛋白质结晶等技术手段,获得CYP337B3(△23)的晶体结构,为深入了解棉铃虫P450酶CYP337B3的结构与功能奠定基础。【方法】对CYP337B3编码基因进行了密码子优化,通过基因重组,将其转化至BL21(DE3)感受态细胞中进行原核表达尝试,通过亲和层析及RESOURCETM Q离子交换层析对CYP337B3(△23)进行体外纯化,利用气相悬滴结晶方法对CYP337B3(△23)进行结晶条件的筛选及X射线晶体衍射。【结果】通过密码子优化,实现了CYP337B3(△23)在大肠杆菌原核表达系统内的大量表达,经过体外纯化及十二烷基硫酸钠-聚丙烯酰胺凝胶电泳检测,CYP337B3(△23)蛋白纯度可达到95%左右,我们对CYP337B3(△23)进行了蛋白结晶条件的筛选,最终获得了CYP337B3(△23)的结晶条件和蛋白晶体。【结论】本文利用气相悬滴结晶方法获得了CYP337B3(△23)的蛋白晶体,为今后CYP337B3的三维结构解析、功能研究以及最终阐述该种新型的棉铃虫抗药机制奠定了良好的基础。     

B3(ds-scFv)靶向超抗原的制备及活性鉴定

To construct the expression vector of a recombinant toxin composed of a disulfide stable single-chain antibody from mAbB3 and SEA(D227A),the binding ability and cytotoxicity of the purified renatured products against the B3 positive carcinoma cells was examined. The VH and VL fragments of the mAbB3 were ligated by overlap PCR, the PCR product was cloned to the pET22b expression vector, then the SEA fragment was inserted into the B3dsscFv-pET22b expression vector which was digested by the same restriction enzymes. The expression plasmid was identified by restriction endonucleases digestion and transformed into E.coli BL21(DE3) followed by IPTG induction. The inclusion body was purified through SP-Sepharose cation exchange column after denaturing and refolding and the binding and cytotoxic ability of the purified products was examined by cell-ELISA and non-radioactive cell proliferation assay seperately. The expression vector B3dsscFv-SEA-pET was constructed successfully and the expression product exists mainly in the inclusion body, amounting to 33% of the total protein. The refolding product remains the binding ability of the single-chain antibody and has cytotoxic effect on HT-29 colon carcinoma cells. The stability assay showed that the resulting protein was stable at 37℃. This genetically engineered B3dsscFv-SEA fusion protein has bifunction of tumor targeting and tumor cell killing and promises to be an effective reagent for tumor targeted immunotherapy.     

B.B.Brodie(1907～1989)

B.B.Brodie博土,一个先驱药理学家和美国国家科学院院士,1989年2月28日逝世。生前是美国国立卫生研究院心脏研究所化学药理实验室的创始人和第一任主任。