%0 Journal Article
%T Overproduction of Cholera Toxin B Subunit by Recombinant Escherichia coli MM2 in Lactate-containing Medium<br>霍乱毒素B亚单位工程菌MM2在含乳酸培养基中的高表达
%A FANG Hong
%A Qing
%A DENG Bing
%A Bing
%A ZHAO Si
%A Qing
%A YU Gong
%A Yi
%A MA Qing
%A Jun
%A <br>方宏清
%A 邓兵兵
%A 赵四清
%A 于公义
%A 马清钧
%J 生物工程学报
%D 2000
%I 
%X The expression of ctb gene in recombinant E. coli MM2 strain is affected by temperature, pH and carbon source. High level production of cholera toxin B subunit (CTB) was investigated in lactate-containing medium which designed by experiments of orthogonal test. Upshifting temperature from 30 degrees C to 37 degrees C could increase the production of CTB by 4 fold, upshifting pH value from 7.2 to 8.4 at the later culture stage could increase the specific expression level of CTB by 2.14 fold, and adding sodium acetate increased the production of CTB by 65%. In 5 L fermentor the cell density was reached at OD600 30, and the 186.7 mg/L of CTB was obtained. The CTB in the culture supernatants was in the form of polymer like the native CTB from Sigma, and also possessed the same antigenity.
%K E
%K coli
%K cholera toxin B subunit
%K temperature
%K lactate
%K pH value<br>大肠杆菌
%K 霍乱毒素B亚单位
%K 温度
%K 乳酸
%K pH值
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A66E90C274451689E69F6F0291467824&aid=15F155EDC08066EB&yid=9806D0D4EAA9BED3&vid=7801E6FC5AE9020C&iid=0B39A22176CE99FB&sid=8575BEDA702C4B7C&eid=F260CE035846B3B8&journal_id=1000-3061&journal_name=生物工程学报&referenced_num=0&reference_num=12