Table 4

Final product concentrations (cP), substrate-specific product yields (YP/S), and volumetric productivities (QP) of fed-batch fermentations of C. glutamicum l-valine and 2-ketoisovalerate producers with either inactivated PDHC or PDHC with reduced activitya

Condition and straincP (g/liter)YP/S (mol C/mol C)QP [g/(liter × h)]
l-Valine overproduction
    C. glutamicum ΔaceE Δpqo (pJC4 ilvBNCE)b24.6 ± 2.60.23 ± 0.020.5 ± 0.1
    C. glutamicum aceE A16 Δpqo Δppc (pJC4 ilvBNCE)83.6 ± 2.60.33 ± 0.011.5 ± 0.1
2-Ketoisovalerate overproduction
    C. glutamicum ΔaceE Δpqo ΔilvE (pJC4 ilvBNCD)c21.8 ± 3.20.26 ± 0.020.5 ± 0.1
    C. glutamicum aceE A16 Δpqo Δppc ΔilvE (pJC4 ilvBNCD)33.7 ± 1.00.21 ± 0.040.7 ± 0.1
  • a Given values represent the arithmetic mean ± standard deviation of at least three independent experiments.

  • b Data are from reference 27.

  • c Data are from reference 11.