| Autor: |
Curless C; Amgen, Inc., Amgen Center, 1840 DeHavilland, Thousand Oaks, California 91320, USA., Fu K, Swank R, Menjares A, Fieschko J, Tsai L |
| Jazyk: |
angličtina |
| Zdroj: |
Biotechnology and bioengineering [Biotechnol Bioeng] 1991 Nov; Vol. 38 (9), pp. 1082-90. |
| DOI: |
10.1002/bit.260380917 |
| Abstrakt: |
A two-stage, cyclic fed-batch fermentation process to produce recombinant human lymphokine was designed. The organism used in the study was Escherichia coli K-12 containing a temperature-sensitive walkaway plasmid bearing an insert which codes for a human lymphokine. Transcription of the recombinant gene is controlled by a lambda repressor/pL promoter system. The lambda promoter is regulated by the temperature-sensitive product of the cl857 gene at 30 degrees C, but at 42 degrees C the promoter is derepressed. The first or growth, stage of the process was maintained at 28 degrees C and operated in the fed-batch mode. The vessel was fed at a rate which gives a constant specific growth rate using a media designed to maintain a constant optical density OD(600) of 50. After the volume in the first stage reached the maximum working volume of the vessel (12 L), a portion of the vessel contents was transferred to the second stage. The second, or induction/product formation, stage also operated in the fed-batch mode, was kept at 42 degrees C, and was fed with a media that is conducive to recombinant human lymphokine synthesis. An optical density of more than 100 was consistently achieved in the second stage. Thirty cycles were completed with a consistent yield of human lymphokine and cell density in each cycle. The process was used to produce 200 L of OD(600) 50 material from the first stage in 10 days. The volumetric productivity (g lymphokine/L. day) of the two-stage, cyclic fed-batch process is twice that of a single-stage, fed-batch fermentation process. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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