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Table 2 Fermentation characteristics of E. coli strain LW393 and its derivatives

From: Metabolic engineering of Escherichia coli for the production of butyric acid at high titer and productivity

Strain Relevant propertya Medium Sugar Cell densityb Butyrate titer (g l−1) qP (g g cells−1 h−1)c QP (g l−1 h−1)d Yield (g g−1 sugar)e
LW393 PTB/BUK LB Glucose 11.0 ± 0.03 19.7 ± 0.1 0.21 ± 0.01 0.47 ± 0.01 0.42 ± 0.01
   LB Xylose 8.2 ± 0.03 25.1 ± 0.4 0.20 ± 0.03 0.36 ± 0.02 0.40 ± 0.01
   Mineral salts Glucose 10.8 ± 0.20 28.4 ± 0.4 0.25 ± 0.04 0.64 ± 0.04 0.37 ± 0.01
   Mineral salts Glucose + YE 10.5 ± 0.40 33.1 ± 0.3 0.26 ± 0.09 0.76 ± 0.04 0.35 ± 0.01
   Mineral salts Xylose 9.4 ± 0.40 27.3 ± 0.8 0.30 ± 0.01 0.60 ± 0.02 0.37 ± 0.01
   Mineral salts Xylose + YE 10.8 ± 0.17 31.7 ± 0.4 0.36 ± 0.03 0.89 ± 0.07 0.37 ± 0.01
LW483 (-PTB/BUK) Mineral salts Glucose 4.7 ± 0.04 14.6 ± 1.0 0.16 ± 0.02 0.20 ± 0.03 0.41 ± 0.01
LW532 LW483, ΔtesB Mineral salts Glucose 2.8 ± 0.20 8.8 ± 0.7 0.19 ± 0.03 0.12 ± 0.03 0.41 ± 0.02
LW612 LW532(ptesB) Mineral salts Glucose + (IPTG, 10 µM) 4.9 ± 0.10 20.1 ± 0.5 ND 0.30 ± 0.01 0.37 ± 0.01
  1. Cultures were grown in LB or AM1 medium with glucose or xylose ± yeast extract (5 g l−1). All media were supplemented with additional trace elements as presented in “Materials and methods”. Fermentations were at 37 °C and the culture pH was maintained at 7.0 by automatic addition of 2 N KOH. N2 was sparged through the culture from the beginning (7 ml min−1) to maintain anaerobic condition
  2. All reported values are average of three independent experiments with standard deviation
  3. a(PTB/BUK), pathway from butyryl-CoA to butyrate utilizes phosphotransbutyrylase and butyrate kinase (Fig. 1). (-PTB/BUK), plasmid p185 encoding ptb and buk was removed from strain LW393. Strain LW612 carries plasmid pLW108 containing E. coli tesB expressed from trc promoter
  4. bCell density is presented as O. D. 420 nm
  5. cqP, specific productivity; unit, g butyrate produced per g dry cell weight per h
  6. dQP, Average volumetric productivity of butyrate over a 24-h period
  7. eYield, g butyrate (g sugar consumed)−1