相容性溶质支持下重组免疫毒素的周质腔可溶表达及葡萄糖对其表达的影响

Compatible-Solute-Supported Periplasmic Expression of Recombinant Immunotoxins and the Effects of Glucose Thereby

在基因工程的实践中,包含体的形成是人们利用大肠杆菌表达外源蛋白的一大难题。本文报道了利用山梨醇、甜菜碱等相容性溶质,在高盐胁迫下,实现了重组免疫毒素在大肠杆菌周质腔中的可溶性表达。同时发现葡萄糖的加入时机对重组免疫毒素的表达量有重要的影响。

Bacteria protect themselves against high external osmolality by uptake or synthesis of a limited number of socalled compatible solutes.Under such extreme conditions,combine factors can facilitate the foreign recombinant protein expression.In our experiment,we added additional NaCl and two compatible solutes (glycine betaine and sorbitol) into the medium.The recombinant immunotoxin BDI(scFv)PE38 was expressed mainly in soluble form and can be purified by Ni2+NTA agarose.We also found the time when the glucose was added into the medium greatly affected the expression level of the recombinant immunotoxin.This suggested that glucose played an important role in the expression system.