Kuboi R, Umakoshi H, Komasawa I
Department of Chemical Engineering, Osaka University, Japan.
Biotechnol Prog. 1995 Mar-Apr;11(2):202-7. doi: 10.1021/bp00032a012.
Escherichia coli cells were found to grow in poly(ethylene glycol) (PEG)/phosphate aqueous two-phase systems by selecting the phase-forming components and their concentrations, the tie-line length, and the phase volume ratio properly. The cells cultivated up to an optical density at 660 nm of 1.0 were disrupted by ultrasonic irradiation to release and recover overproduced beta-galactosidase. The surviving cells were found to grow immediately after ultrasonic irradiation. The PEG/phosphate (KH2-PO4-K2HPO4) system with added Na2SO4 was the one optimized for extractive cultivation of E. coli cells, where beta-galactosidase was selectively partitioned to the top phase while total soluble proteins and cells partitioned to the bottom phase. This integrated process was extended to a semicontinuous operating mode, where the top phase containing beta-galactosidase was removed following intermittent ultrasonic irradiation and the bottom phase containing cells was recycled together with the new top phase solution to repeat production and recovery of beta-galactosidase.
通过适当选择相形成成分及其浓度、系线长度和相体积比，发现大肠杆菌细胞能够在聚乙二醇（PEG）/磷酸盐双水相体系中生长。将培养至660nm处光密度为1.0的细胞通过超声辐照进行破碎，以释放并回收过量表达的β-半乳糖苷酶。发现存活的细胞在超声辐照后立即开始生长。添加了Na2SO4的PEG/磷酸盐（KH2-PO4-K2HPO4）体系是用于大肠杆菌细胞萃取培养的优化体系，其中β-半乳糖苷酶选择性地分配到上相中，而总可溶性蛋白质和细胞则分配到下相中。这个集成过程扩展到了半连续操作模式，即间歇性超声辐照后，去除含有β-半乳糖苷酶的上相，将含有细胞的下相与新的上相溶液一起循环，以重复β-半乳糖苷酶的生产和回收。
