Fig. 5

Comparative analysis of UTR5 to improve the productivity of butyrate and 2,3-butanediol. a Schematic metabolic pathway for the production of a butyrate and b 2,3-butanediol. The flux for the TCA cycle was included in the 2,3-butanediol system due to the presence of oxygen. The dotted red and blue arrows indicate controlled glycolytic flux and additional carbon flux from glycolysis to the product-forming pathway, respectively (dotted black outer lines). c The productivity (red) and yield (blue) of butyrate were compared after 24 h of fermentation in TB medium. d The productivity (red) and yield (blue) of 2,3-butanediol were calculated after 39 h of cultivation in modified M9 medium. The error bars indicate standard deviations of measurements from two independent cultures