Table 3.
l-Valine production, l-valine and by-product yield on glucose, and glucose consumption of C. glutamicum strains after 24 h under oxygen deprivation
| Strain | Production of: |
Glucose consumptiona (mM) | |||||
|---|---|---|---|---|---|---|---|
|
l-Valine |
Alanineb (%) | Lactateb (%) | Succinateb (%) | Acetateb (%) | |||
| mMa | %b | ||||||
| ΔLP | 4.4 ± 1.8 | 10.7 ± 1.8 | 21.5 ± 2.3 | 10.1 ± 1.4 | 3.8 ± 0.3 | 6.8 ± 0.4 | 40 ± 10 |
| Val-1 (BNCTMDLD/ΔLP) | 106 ± 26 | 64.0 ± 1.1 | 10.0 ± 0.5 | 1.6 ± 0.5 | 7.1 ± 1.5 | 4.8 ± 0.2 | 166 ± 42 |
| Val-2 (BNCTMDLD/ΔLP_ΔAc) | 332 ± 87 | 70.6 ± 1.1 | 11.7 ± 2.2 | 0.9 ± 0.2 | 8.6 ± 1.2 | 1.6 ± 0.2 | 472 ± 129 |
| Val-3 (BNCTMDLD/ΔLP_+GP) | 956 ± 58 | 75.5 ± 2.1 | 5.8 ± 0.6 | 0.9 ± 0.0 | 9.0 ± 0.5 | 1.5 ± 0.1 | 1,270 ± 70 |
| Val-4 (BNCTMDLD/ΔLP_ΔAc+GP) | 1,120 ± 70 | 74.7 ± 1.0 | 5.5 ± 0.5 | 0.7 ± 0.0 | 10.1 ± 0.7 | 1.0 ± 0.0 | 1,500 ± 80 |
| Val-5 (BNGECTMDLD/ΔLP_ΔAc+GP) | 902 ± 33 | 86.4 ± 0.8 | 2.4 ± 0.3 | 1.1 ± 0.0 | 5.7 ± 0.2 | 0.6 ± 0.0 | 1,040 ± 30 |
| Val-6 (BNGECTMDLD/ΔLP_ΔAc+GP_ilvNGE) | 822 ± 28 | 85.8 ± 1.0 | 2.7 ± 0.3 | 1.1 ± 0.0 | 5.3 ± 0.2 | 0.6 ± 0.0 | 958 ± 29 |
| Val-7 (BNGECTMDLD/ΔLP_ΔAc+GP_ilvCTM) | 1,210 ± 60 | 84.0 ± 0.8 | 1.8 ± 0.1 | 0.8 ± 0.1 | 4.4 ± 0.2 | 0.6 ± 0.0 | 1,440 ± 80 |
| Val-8 (BNGECTMDLD/ΔLP_ΔAc+GP_ilvNGECTM) | 1,250 ± 50 | 86.4 ± 1.0 | 2.6 ± 0.3 | 0.8 ± 0.1 | 4.6 ± 0.3 | 0.6 ± 0.0 | 1,440 ± 50 |
| Val-9 (BNGECTMDLD/ΔLP_ΔAc+GP_ilvNGECTM_ΔAla) | 1,280 ± 100 | 88.4 ± 0.8 | 0.4 ± 0.1 | 0.8 ± 0.1 | 4.6 ± 0.4 | 0.6 ± 0.0 | 1,440 ± 110 |
a
l-Valine production and glucose consumption values were corrected for dilution caused by the addition of NH3 solution and glucose throughout the reaction.
b
Yield is expressed as a percentage of the theoretical yield (100% means 1 mol of l-valine or 2 mol of alanine and organic acids produced per 1 mol of glucose consumed). Cell concentration was 40 g cell dry weight liter−1. The data represent an average of three independent experiments.