【摘要】 利用RT-PCR技术获得大豆过氧化氢酶GmCAT3和GmCAT5基因的cDNA片断,序列长为1 492 bp,编码492个氨基酸,相对分子质量分别为56.9和56.7 kD,等电点(pI)都为6.77,同时预测了蛋白质的二级和高级结构;将获得的目的片段连接到pBV220表达载体上,转化大肠杆菌BL21(DE3)进行诱导表达,经SDS-PAGE电泳分析,在42℃诱导6 h的条件下,蛋白的表达量最佳,诱导的目的蛋白在57 kD处主要以包涵体的形式存在,获得重组蛋白占总蛋白的百分比分别是47%和35%,为近一步研究大豆过氧化氢酶的结构和功能提供了实验基础.更多还原

【Abstract】 GmCAT3 and GmCAT5 cDNA were amplified by RT-PCR.The length of the genes were 1 492 bp,which encoded 492 amino acids.The molecular weight of the enzymes were 56.9 and 56.7 kD respectively,and the pI were both 6.77,the second and third structures of the proteins encoded were predicted.The tar-get genes were ligated to expression vector pBV220,then transformed into E.coli BL21(DE3) and induced.The expression products were identified by SDS-PAGE.The optimal expression conditions of genes were 6 h under 42 ℃.They were expressed 57 kD molecular weight specific proteins as inclusion bodies.The propor-tion of proteins induced in total bacterial proteins were 47% and 35% under the certain conditions.The work provided the foundation for further studying the structure and function of the soybean catalases.更多还原