Highly efficient L-lactate production using engineered Escherichia coli with dissimilar temperature optima for L-lactate formation and cell growth

Table 4 Comparison of fermentation data (mean ± range of duplicate experiments) from the bioreactor experiments

Strains	Overall volumetric lactate productivity (g/l h)^a	Oxygen-limited volumetric lactate productivity (g/l h)^b	Oxygen-limited specific lactate productivity (g/g h)^c	Oxygen-limited specific glucose consumption rate (g/g h)^d	Aerobic biomass yield (g/100 g glucose)^e	Oxygen-limited lactate yield (g/100 g glucose)^f	Lactate titer (g/l)	Yield (g/100 g glucose) (The molar yield)^g
								biomass	lactate	acetate	succinate	pyruvate
090B3 ^h	2.67 ± 0.10	3.46 ± 0.23	0.42 ± 0.00	0.50 ± 0.01	36.9 ± 0.2	83.0 ± 1.2	106.8 ± 1.1	5.8 ± 0.1	74.3 ± 1.2 (1.49 ± 0.02)	0.6 ± 0.1	0.3 ± 0.0	0.0 ± 0.0
090B3 ⁱ	4.66 ± 0.12	6.77 ± 0. 30	0.98 ± 0.10	0.97 ± 0. 04	36.8 ± 0.1	97.0 ± 0.5	142.2 ± 0.7	4.9 ± 0.3	87.0 ± 2.1 (1.74 ± 0.04)	0.4 ± 0.1	0.1 ± 0.1	0.1 ± 0.2

^aAverage volumetric productivity for lactate during the overall fermentation process.
^bAverage volumetric productivity for lactate during the oxygen-limited phase.
^cAverage specific lactate productivity during the oxygen-limited phase. The molar yield was also presented in parentheses.
^dAverage specific glucose consumption rate during the oxygen-limited phase.
^eAverage biomass yield during aerobic phase.
^fAverage lactate yield during the oxygen-limited phase.
^gAverage yield during the overall fermentation process.
^hThe fermentation was carried out with aerobic cell growth at 37°C followed by fermentation at 37°C.
ⁱThe fermentation was carried out with aerobic cell growth at 37°C followed by fermentation at 42°C.

ISSN: 1475-2859