中国化学工程学报(英文版)
中國化學工程學報(英文版)
중국화학공정학보(영문판)
CHINESE JOURNAL OF CHEMICAL ENGINEERING
2007年
5期
760-764
,共5页
韩云%李志敏%杜鹏%甘人宝%叶勤
韓雲%李誌敏%杜鵬%甘人寶%葉勤
한운%리지민%두붕%감인보%협근
human epidermal growth factor%acetate-tolerance%Escherichia coli%pH
An acetate-tolerant mutant of Escherichia coli DH5α, DA19, was used for secretory production of human epidermal growth factor (hEGF) whose expression was under the control of phoA promoter. The recombinant cells were cultured in a chemically defined medium, and glucose was added at different specific provision rates during the growth and expression phases. It was found that pH had a significant effect on the extracellular hEGF production. The extracellular hEGF concentration was 75.5mg·L-1, 5.2-fold of the level reached at pH 7.0, even though more acetate was produced. Nitrogen source was limited in the later growth phase. Supplementation of ammonium promoted the consumption of phosphate and reduced the time to exhaust phosphate, but the extracellular hEGF production was similar to that without supplementation of ammonium.
