Author(s):
Rocha, I.
; Carneiro, S.
; Veloso, Ana C. A.
; Ferreira, E. C.
Date: 2005
Persistent ID: http://hdl.handle.net/1822/5128
Origin: RepositóriUM - Universidade do Minho
Description
Escherichia coli has been the organism of choice for the production of many
recombinant proteins with high therapeutic value. However, while the research
on molecular biology has allowed the development of very strong promoters,
there are still some phenomena associated with this process that hamper the full
use of those technologies: aerobic acetate production associated with high
specific growth rates, and the so-called stringent response that usually occurs
when very high levels of heterologous protein production takes place. In both
cases, productivity is affected due to a decrease in the specific growth and
production rates. In this work, a systems biology approach for modelling
recombinant protein production processes was used aiming its optimization. The
existing genome-scale metabolic model of Escherichia coli was modified by
including an equation for protein production (the model protein GFP – Green
Florescent Protein), based on its amino acids content. For the validation of the
genome-scale model in high-cell density processes, highly reproducible fed-batch
fermentations are run with constant specific growth rate. The developed data
acquisition and control system allows to control the substrate addition rate, and
to acquire on-line the fermenter’s weight, to calculate oxygen and carbon dioxide
transfer rates, as well as to obtain glucose and acetate concentrations using a
developed Flow Injection Analysis system.