%0 Journal Article
%@ 0268-2575
%A Ganduri, V.S.R.K.
%A Ghosh, Sanjoy
%A Patnaik, P R
%D 2005
%F open:988
%I wiley/Society of Chemical Industry
%J Journal of Chemical Technology & Biotechnology
%K recombinant fermentations; plasmid stability; incomplete mixing; distribution of mixing
%N 4
%P 361-370
%T Optimal mixing to improve the performance of batch and continuous fermentations with recombinantEscherichia coli
%U http://crdd.osdd.net/open/988/
%V 80
%X Fermentations with genetically altered bacteria tend to lose plasmids as the fermentation  progresses. Methods such as two-stage cultivation, cell recycle and the addition of antibiotics are  commonly used to enhance plasmid stability. Here we examine a different method, the regulation of  mixing in the bioreactor. In particular, large bioreactors are considered where uniform mixing is difficult  to achieve and the probability of plasmid loss varies with the specific growth rate. For both batch and  continuous cultivations of Escherichia coli C600 gal K containing the plasmid pBR Eco gap, it is seen  through a model that bothmodes of operation exhibit high plasmid stability and cell growth when the broth  is incompletely mixed, and mixing near and away from the point of inoculation are unequal. Thus, the  natural incomplete mixing in large bioreactors may be utilized to improve plasmid stability. A practical  method to implement this idea is suggested.
%Z Copyright of this article belongs to Wiley/Society of Chemical Industry.