초록
<P><B>Abstract</B></P><P><B>BACKGROUND:</B> Succinic acid is a valuable four‐carbon organic chemical with applications in many fields. It was found that cell mass was an important factor in succinic acid production by metabolically engineered <I>Escherichia coli</I> strains. In this work, high cell density fermentation was investigated for succinic acid production by a metabolically engineered strain SD121 with <I>ldhA, pflB, ptsG</I> mutation and heterogenous cyanobacterial <I>ppc</I> overexpression.</P><P><B>RESULTS:</B> Under two‐stage cultivation, the controlled DO feeding strategy during the aerobic growth phase facilitated biomass up to a dry cell weight of 19.6 g L<SUP>−1</SUP>, and enhanced succinic acid production in the following anaerobic fermentation phase to a concentration of 116.2 g L<SUP>−1</SUP>. A near theoretical maximum succinic acid yield of 1.73 mol mol<SUP>−1</SUP> glucose was achieved with an average productivity of 1.55 g L<SUP>−1</SUP> h<SUP>−1</SUP>.</P><P><B>CONCLUSION:</B> The results indicated the potential advantage of high cell density fermentation for improvement of succinic acid production by <I>E. coli</I>. Copyright © 2010 Society of Chemical Industry</P>