초록
<P><B>Abstract</B></P> <P>Production of homo-organic acids without byproducts is an important challenge in bioprocess engineering to minimize operation cost for separation processes. In this study, we used multi-objective optimization to design <I>Escherichia coli</I> strains with the goals of maximally producing target organic acids, while maintaining sufficiently high growth rate and minimizing the secretion of undesired byproducts. Homo-productions of acetic, lactic and succinic acids were targeted as examples. Engineered <I>E. coli</I> strains capable of producing homo-acetic and homo-lactic acids could be developed by taking this systems approach for the minimal identification of gene knockout targets. Also, failure to predict effective gene knockout targets for the homo-succinic acid production suggests that the multi-objective optimization is useful in assessing the suitability of a microorganism as a host strain for the production of a homo-organic acid. The systems metabolic engineering-based approach reported here should be applicable to the production of other industrially important organic acids.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Producing homo-organic acids is critical for reducing purification costs. </LI> <LI> Gene targets predicted from multi-objective optimization minimize byproducts. </LI> <LI> Production of homo-acetic and lactic acids is experimentally demonstrated. </LI> <LI> Random sampling of fluxes reveals metabolic cues for minimal byproducts. </LI> <LI> The constructed strains can be used as base strains for further engineering. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>