Figure 3
Xylose consumption and L-lactic acid production in anaerobic cultivation. Concentration (g l−1) of D-xylose consumed (A) and L-lactic acid produced (B) in anaerobic cultivations of C. sonorensis ldhL strains with the native D-xylose pathway disrupted and expressing XYLA alone (C311, XYLA, xyl1Δ; C313, 2*XYLA, xyl1Δ) or together with ScXKS1 (C341-C342, XYLA, ScXKS1, xyl1Δ; C345-C346, XYLA, ScXKS1, xyl1Δ, xyl2Δ; C348, 2*XYLA, ScXKS1, xyl1Δ; C349, 2*XYLA, ScXKS1, xyl1Δ, xyl2Δ), with C29 as the control. Strains were cultivated at 30°C in 50 ml of CaCO3-buffered, YP-50 g l−1 D-xylose with 10 mM MgCl2 in 100 ml flasks sealed with water locks for 146 h. Initial OD600 was 12. Results are averages of duplicate flasks. Error bars indicate sem. Bars with the same letter (a to d) in the same graph did not differ significantly (p > 0.05).