We have constructed a new expression vector by introducing T7 phage gene 10 SD sequence and T7terminator sequence into multicloning sites of p~(GEM7Zf)(+). This vector has following characteristics:1.The 8bp opti-mal distance between SD and ATG;

• 以p~(GEM7Zf(+))为出发质粒；在其多克隆位点两端加入T7 phage gene 10的SD序列和T7 terminator 序列；构建成一个新的表达载体；它具有如下特点:1.；SD 保守序列AGGAG 至ATG 之间8bp 的最佳间隔;