Figure 1
Characterization of PDC knock-out strains. (A) Southern analysis of C. sonorensis wild type, pdc1∆, pdc2∆, and pdc1∆ pdc2∆ strains with PDC1, PDC2, MEL5, and G418R probes. (B) PDC enzyme activity in C. sonorensis transformants expressed as units per mg protein (U/mg). Lower case letters indicate gene deletion and upper case letters the presence of an intact PDC gene. Activity was measured at 20 h (white columns) and 40 h (black columns) from cultures grown on YP +% (w/v) glucose medium. Data are means ± SEM (n=2). Biomass (C) and concentrations of ethanol (D), pyruvate (E), and glucose (F) of C. sonorensis wild type (○), pdc1∆ (∆), pdc2∆ (□), and pdc1∆ pdc2∆ (⋄) strains in cultures grown on YP + 5% (w/v) glucose medium. Data are means ± SEM (n=3-4). Where no error bars are seen, SEM was less than the size of the symbol.