FIGURE 4.

γ-PGA synthesis as a function of xylose concentration for B. subtilis PG10. The γ-PGA concentration was determined by the CTAB Assay and is shown as the turbidity at 400 nm. The strains tested were the non-γ-PGA producing negative control B. subtilisΔxylAB and B. subtilis PG10 with five different xylose concentrations as inducer for pgs gene expression. The γ-PGA production was determined during the exponential growth phase (after 9 h, compare Figure 1) for biological triplicates. The error bars represent the standard deviation.