초록
<P><B>Abstract</B></P> <P>Glucose from plant cellulose and glycerol from the waste stream of the biodiesel production process are two most abundant and renewable carbon sources. <I>n</I>-Butanol is an alternative fuel of potential and its production by microbes which utilize the two carbons appears to be industrially incentive on the ground of sustainability and economy. However, the hierarchical regulation of glucose dictates <I>Escherichia coli</I> to prefer utilization of glucose over others. This physiological behavior of the cell prolongs the fermentation process and eventually reduces productivity. In this study, a single strain capable of co-utilizing glucose and glycerol was developed by metabolic engineering. Meanwhile, a dual-culture system was also designed by construction of a glucose-selecting and a glycerol-selecting strain. As a consequence, both approaches result in the strains for effective co-utilization of glucose and glycerol. In particular, the single strain enabled production of 6.2 g/L <I>n</I>-butanol, which leads to the conversion yield and productivity accounting for 76.5% of the theoretical and 0.17 g/L/h, respectively. It indicates a promise of the developed technology platform for microbial production of <I>n</I>-butanol from the glucose–glycerol mixture.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Metabolic engineering of <I>Escherichia coli</I> for the <I>n</I>-butanol production. </LI> <LI> Development of a single strain that co-utilizes glucose and glycerol. </LI> <LI> Development of a dual culture system consisting of the glucose-selecting strain and the glycerol-selecting strain. </LI> <LI> Effective production of <I>n</I>-butanol by engineered strains that co-metabolize the sugar mixture. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>