摘要
研究了不同浓度表面活性剂Tween-80,Triton X-100,SDS对大肠杆菌生产α-环糊精葡萄糖基转移酶(α-CGT酶)的影响。结果表明:发酵初始添加Tween-80和Triton X-100的最适浓度分别为2%,0.5%,最终胞外酶活分别达2.03U/ml和4.92U/ml,相对于未添加表面活性剂时提高4.6倍和12.67倍,且改变添加时间不能提高酶的产量;发酵36h添加0.02%SDS对α-CGT酶产量促进最大,最终胞外酶活达5.31U/ml,较对照组提高12.75倍。表面活性剂对α-CGT酶生产的促进作用可能是由大肠杆菌细胞内外膜渗透性增加所致,使细胞周质空间中α-CGT酶能更加快速地渗透到胞外。
The effect of surfactants on the production of recombinant extracellular α-CGTase in E. coli was studied. The result indicated that the optimum concentration of Tween-80 and Triton X-100 are 2% and 0.5% when addition time of surfactant was performed at the beginning of culture. In such condition, α-CGTase activity of culture supernatant reached 2.03 U/ml for Tween-80 and 4.92 U/ml for Triton X-100 and were respectively 4.6 and 12.67 higher than that without addition of surfactant. The different addition time during culture stage could not further improve the yield. When adding 0.02% SDS at 20 h culture, the final yield of enzyme could reach to 5.31 U/ml, which was 12.75 times higher than that of control. The enhanced extracellular secretion of α-CGTase by surfactants is possibly caused by the increasing of the cell membrane pemeabilization of E. coli.
出处
《中国生物工程杂志》
CAS
CSCD
北大核心
2009年第7期56-61,共6页
China Biotechnology
基金
国家杰出青年基金(20625619)
江苏省自然科学基金(BK2007019)资助项目
