【摘要】 利用重叠PCR技术突变了sea基因上一个稀有密码子簇 ,将此段中稀有密码子全部更换成E .coli最常用密码子 ,得到seam 。将sea和seam 分别克隆于 7ZTS表达载体上 ,并转化JM10 9(DE3)菌株。结果表明 ,sea基因的表达十分微弱 ,而seam 基因的表达量十分高 ,约占菌体总蛋白的 15 %。表达产物在体内具有一定的抗肿瘤活性。更多还原

【Abstract】 The rare codons of a fragment in staphylococcal enterotoxin A gene were turned into the most high usage frequency codons in E.coli by overlap PCR technique. Genes of sea and sea m were cloned into 7ZTS expression vector and transformed into JM109(DE3),respectively. The result shows that expression level of sea gene was very low, but the expression level of sea m was as high as 15% of total cell proteins. The expression product shows activity of antitumor in vivo .更多还原