乙肝病毒融合表面抗原SA-28基因在酵母中的表达

Expression of a Modified HBsAg Gene SA-28 in Yeast

利用基因工程技术，先将乙肝病毒表面抗原S－preSI融合基因SA－28置于酵母杂合启动子ADH2－SUC2的控制下，然后将SA－28基因的表达单元插入高稳定质粒PHCll的BamHI位点，构建成表达质粒YFD150和YFD150－o，并将其转化酿酒酵母Y19。对转化子表达SA－28基因的研究表明：表达受葡萄糖浓度调控；表达产物具有S和preS1双重抗原性，并形成密度为1．20—1．229／ml的颗粒。

The Hybrid antigen gene SA-28 coding for a modified Hepatitis B surface antigen and preS1 epitope was ligated with a synthetic adaptor and placed at down stream of a hybrid promoter ADH2-SUC2. The expression cassatte was then inserted into BamHI site of highly stable plasmid pHC11 to construct expression vectors, YFD150 and YFD150-o. After transforming them into yeast Y19, the expression of SA-28 gene was studied. The results showed that the expression of SA-28 gene was regulated by glucose concentration. The expressed product had both HBsAg and preS1 antigenicity and it could be assembled into paraticles with the density of 1. 20-1. 22g/ml.