Fig. 7
From: Metabolic engineering of Escherichia coli for efficient production of l-alanyl-l-glutamine
Optimization of the conditions for whole-cell biocatalysis. a Effects of pH on AQ production by strain p15/AQ10. b Effects of temperature on AQ production by p15/AQ10. c Effects of different glucose feeding strategies on AQ production. Feeding strategy: (1) 50 mM glucose was added at once; (2) 10 mM glucose was added every 3 h; (3) 20 mM glucose was added every 3 h. d Effects of the initial alanine concentration on AQ production. Initial alanine concentrations of 100–200 mM were combined with a fixed glutamic acid concentration at 100 mM, and the reaction was performed for 12 h. e Time profiles of the AQ, glutamine, glutamic acid and alanine concentrations. The bioconversion was performed in a reaction mixture containing 100 mM sodium glutamate, 125 mM alanine, 200 mM ammonium chloride, and 10 mM magnesium chloride at 30 °C and pH 9.0