Fed batch culture with declining specific growth rate for high-yielding production of a plasmid containing a gene therapy sequence in Escherichia coli DH1

Using a linear fed batch culture system, we obtained a yield of 296 mgDNA L−1 of a non-expressing plasmid containing a gene therapy sequence in Escherichia coli DH1 bioreactor culture. We propose that we exploited a transient increase in specific plasmid content, first observed during the adaptation from batch to chemostat culture, by inducing a progressive down-regulation of growth rate during our fed batch culture.