The Effects of Recombinant Protein Expression on the Growth and Metabolism of Mammalian Cells

Abstract

The maintenanee of high plasmid eopy-number and the over-expression of foreign proteins in reeombinant bacteria and yeasts is known to resuh in a metabolie load, whieh adversely affects the growth rate. Reports suggest that recombinant mammalian systems are similarly affected, however in eomparison to bacterial systems, relatively little information exists. It was the aim of this study to test the effects of reeombinant gene expression on the growth and metabolism oftwo industrially important mammalian eell lines. BHK 570 and CHo..Kl eells were stably transfected with the human gastric inhibitory peptide (h-GIP) and glucagon reeeptor respectively. Selection was by way ofthe neomycin resistance (neo') gene using G418 as the selective agent. On removal of G418, production of both receptors was stable for the course of the experiments. The growth and metabolism of both cell lines was affected by the presenee of G418 in a manner indicative of an increased metabolie load, eaused by over-expression of the neo' protein. The two eell lines differed in their response to the metabolie load, suggesting a cell-line or clone dependent response. Growth under the increased metabolie load could be modulated by serum, insulin and glutamine addition to the growth medium. Implications for the use of G418 are discussed.

Dealing with the genetic load in bacterial synthetic biology circuits: convergences with the Ohm's law

“…Finally, previous evidence regarding the genetic load in eukaryotic systems ( 29 – 31 ) suggests that gene expression being affected by genetic load may not be exclusive to bacteria. Further experimental and mathematical research should be devoted to clarifying this issue.…”

Restoring the ON Switch in Blind Retinas: Opto-mGluR6, a Next-Generation, Cell-Tailored Optogenetic Tool

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Development of apoptosis‐resistant dihydrofolate reductase‐deficient Chinese hamster ovary cell line

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