Effect of Preinduction Specific Growth Rate on Recombinant Alpha Consensus Interferon Synthesis in Escherichia coli

Abstract

The effect of preinduction specific growth rate on the yield of recombinant alpha consensus interferon in Escherichia coli K-12 was investigated. The cells used in the investigation contain a temperature-sensitive, walkaway plasmid bearing an insert that codes for alpha consensus interferon. Transcription of the recombinant gene is controlled by a lambda repressor/pL promoter system. The lambda promoter is regulated by the temperature-sensitive gene cI857 at 30 degrees C, but at 42 degrees C the promoter is derepressed. The cells were grown under glucose-limited conditions in a chemostat at pH 7 and 30 degrees C. Once steady state was achieved, the vessel temperature was raised to 42 degrees C and a fed-batch mode was initiated. Six dilution rates ranging from 0.025/h to 0.2/h were investigated. Cell dry weight, alpha consensus interferon content, glucose concentration, acetate concentration, and plasmid stability were measured. At each dilution rate, the expression level of alpha consensus interferon (g/g of cell dry wt) reached its maximum value approximately 3 h after induction. In addition, the expression level of alpha consensus interferon increases 4-fold as the dilution rate prior to induction is increased from 0.025/h to 0.2/h. Consequently, the expression of recombinant protein produced by E. coli is dependent on the preinduction specific growth rate.

Recombinant protein production in an Escherichia coli reduced genome strain

“…Fed-batch fermentations were used to assess E. coli MDS40 at three different the fed-batch growth rates: 0.15 h −1 (low), 0.25 h −1 (intermediate), and 0.5 hr −1 (high), where the batch phase growth rates were not different. The parent strain, E. coli MG1655, was only assessed at 0.25 h −1 , as the behavior of E. coli MG1655 and other related strains has been well investigated with respect to recombinant protein productivity at these controlled growth rates (Curless et al, 1990;Hellmuth et al, 1994;Sanden et al, 2003;Turner et al, 1994). The growth curves for E. coli MG1655 and MDS40 are shown in Figure 2.…”

Effects of growth rate on cell extract performance in cell‐free protein synthesis

“…Curless et al (1990) reported that specific productivity (g protein/g DCW/ h) increased with increasing pre-induction growth rate, even though the post-induction growth rate was constant. In addition, Park et al (1990) showed that protein production per plasmid increased with faster growth during expression.…”

Solubility and proteolysis of the Zb‐MalE and Zb‐MalE31 proteins during overproduction in Escherichia coli

“…Several authors have stressed the importance of the selected feed profile in fed-batch cultivation as a major factor controlling the levels of bioproduction (Curless et al, 1990;Hellmuth et al, 1994;Shin et al, 1998;Zabriskie et al, 1987). Through use of the fed-batch technique the cell accumulation and thus the growth rate can be controlled.…”