bioreactor studies of heterologous protein production by ...

detennined in the cunent study, the model was able to simulate the fiaction of plasmid-
bearing cells of the cited nxombinant strain. Coppella and Dhurjati also developed an
excenent smcnired model to descnbe the recombinant yeast (Coppeb and Dhq0ati,
1990). But their model required 43 equatioas and 48 parameters and some parameters
were dificuit to estimate. Its complexity poses a number of diEicuIties for its practical use
(e.g. parameter estimations). In con- the present model requins 15 equations and 18
experimentaliy accessible parameters. It is more realistic and useful for industriai
applications.
In order to further test the proposed mode4 another set of experimental data on
die growth of recombinant S. cerevisiue SEY2102/pRB58 wen obtained h m Parker and
Seo (1992). The host saain SEY 2102 contained the plasmid pBR58. which encodes for
intraceilular invertase. The dynamics of ce1 growth. glucose consumption and ethanol
metabohm wen sirnuiated by the modeL Dw to inadequate data, the simulation for
invertase production could not be presented. Figure 5.4 shows a remarkable agreement
benHeen the model simulations and the reported dam In executing the model. the same
parameter values hted in Table I were used except the value of p~, iJ,, and th, which were
set to 0.10 If' and 1.5 h respectively to match the observed values. Thus. the general
applicability of the present model was furcher confîmed.