摘要
为了减少rIL-2工程菌高密度培养时乙酸的积累,在诱导阶段对该工程菌进行细胞再循环培养的研究,比较了细胞再循环补料液、pH、细胞循环培养时间段对工程菌的生长及rIL-2表达的影响。结果表明在菌密度D_(600)为50时,细胞再循环补料液中酵母抽提物与胰蛋白胨浓度为发酵培养基的5倍就能满足rIL-2表达的需求,同时选择诱导后4～6h之间的细胞再循环培养能有效地防止乙酸的过高积累并减少营养物质的损失,有利于rIL-2的表达。根据以上研究结果得到了rIL-2工程菌诱导阶段细胞再循环培养方法,使得在诱导前菌密度D_(600)为50左右时rIL-2的表达水平约为40％。
To reduce the acetate accumulation in high density culture of recombinanl E.coli expressing rIL-2, we developed a cell recycle fermenter(5 L) with hollow fiber was used as the separation mould. Cell recycle was began after induction. The effects of recycle medium, recycle stage and pH on the rIL-2 expression level were studied. Results showed that at an D600 of 50, the concentration of yeast and tryptone must at least 5 times as that of the basic medium to meet the high level expression of rIL-2, and recycle should be better performed from 4 - 6 h after induction to prevent the accumulation of acetic acid and reduced the loss of nutrient. Then after 6 -7 h of induction, acetic acid accumulation was 4- 5 g/L and the production of rIL-2 reached to 40% of total cellular protein.
出处
《生物技术通讯》
CAS
1998年第2期106-110,120,共6页
Letters in Biotechnology
