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Table 3 3-amino-4-hydroxybenzoic acid (3,4-AHBA) production from glucose by metabolically engineered strains of C. glutamicum

From: Enhanced production of γ-amino acid 3-amino-4-hydroxybenzoic acid by recombinant Corynebacterium glutamicum under oxygen limitation

  Parent
(KT01)
Δldh
(HKC5037)
ΔpqoΔcatΔpta-ackA (HKC5052) ΔalaTΔavtAc
(HKC5051)
Δmdh
(HKC5057)
3,4-AHBA (g/L)a 1.140 ± 0.085 1.950 ± 0.283 0.906 ± 0.199 1.190 ± 0.046 0.030 ± 0.017
Cell growth (g DCW/L)a 7.2 ± 0.3 3.5 ± 0.5 2.9 ± 0.6 6.6 ± 0.9 2.8 ± 1.1
Specific productivity
(mg/h/g DCW)a
157.9 ± 5.7 561.7 ± 1.2 314.8 ± 31.5 183.3 ± 24.0 14.6 ± 15.1
Relative productivity (%)b 100 ± 4 365 ± 1 205 ± 20 119 ± 16 10 ± 10
By-product      
Lactate (g/L)a 1.12 ± 0.35 N.D. N.D. 0.54 ± 0.10 0.02 ± 0.01
Acetate (g/L)a 2.88 ± 0.81 0.90 ± 0.49 0.81 ± 0.01 1.63 ± 0.22 N.D.
Succinate (g/L)a 3.39 ± 0.28 N.D. N.D. 0.39 ± 0.39 N.D.
Ala (g/L)a 1.51 ± 0.07 0.54 ± 0.02 0.63 ± 0.02 0.21 ± 0.04 N.D.
Val (g/L)a 0.92 ± 0.01 0.69 ± 0.07 0.66 ± 0.00 0.60 ± 0.11 N.D.
Lys (g/L)a 1.30 ± 0.06 1.60 ± 0.18 2.86 ± 0.07 4.06 ± 0.08 2.55 ± 0.49
Total amounts of by-product (g/L) 11.12 3.73 4.96 7.43 2.57
  1. N.D. not detected
  2. aValues were determined after 100 h of cultivation. Data are presented as the mean ± standard deviation calculated from the results of duplicate independent experiments. Specific productivity was determined based on dry cell weight (DCW) after 100 h of cultivation. All strains were grown under aerobic conditions until the late log phase in brain heart infusion medium, and the cultures were then inoculated at an initial OD600 of 0.2 into modified mineral salt CGX II medium containing glucose (40 g/L) as the sole carbon source
  3. bRelative productivity was determined based on the specific productivity of 3,4-AHBA
  4. cFor 3,4-AHBA production, alanine (final 100 mg/L) was added to CGX II medium because this mutant required alanine for cell growth