Fig. 4From: Gene modification of Escherichia coli and incorporation of process control to decrease acetate accumulation and increase ʟ-tryptophan productionʟ-Tryptophan production in a fermentation with a dissolved oxygen (DO) level of 30% and the application of glucose feedback feeding. a Open squares concentration of glucose and filled squares acetate levels. b Filled squares biomass, and open squares ʟ-tryptophan levels (P < 0.05)Back to article page