Table 1.
Strains, plasmids, and primers used in this study.
Fig 1.
Schematic diagram illustrating the workflow of the cell recycling bioreactor and four cell recycling strategies adopted.
Fig 2.
Analysis of process parameters in L-tryptophan production by using the strain TRTHB (P<0.05).
Fig 3.
Effect of modifying the genes required for acetate synthesis on biomass and production of L-tryptophan in L-tryptophan fermentation (P<0.05).
Fig 4.
Effect of modifying the genes required for acetate synthesis on accumulation of acetate and glucose conversion rate in L-tryptophan fermentation (P<0.05).
Fig 5.
The metabolic flux distribution of TRTHB and TRTHBPA during the later fermentation period (30–40 h) of L-tryptophan production.
Values in parentheses represent the metabolic flux of TRTHBPA.
Fig 6.
Effect of a cell recycle strategy on biomass and production of L-tryptophan in L-tryptophan fermentation by TRTHBPA (P<0.05).
Fig 7.
Comparisons of biomass (a), L-tryptophan production and fermentation period (b) in L-tryptophan fermentation by TRTHBPA between strategy I and the control (without cell recycling).
Fig 8.
Effect of a cell recycle strategy on accumulation of acetate and glucose conversion rate of L-tryptophan in L-tryptophan fermentation by TRTHBPA (P<0.05).
Fig 9.
The linear relation of cell and tryptophan biosynthesis during cell recycling period (20–26 h) with strategy I and III.