Elimination of carbon catabolite repression in Clostridium acetobutylicum—a journey toward simultaneous use of xylose and glucose

The industrial Gram-positive anaerobe Clostridium acetobutylicum is a valued acetone, butanol, and ethanol (ABE) solvent producer that is able to utilize a vast array of carbon sources in fermentation. When glucose is present in the growth medium, however, C. acetobutylicum, like many Gram-positive organisms, exhibits biphasic growth characteristics in which glucose is used preferentially over secondary carbon sources, a phenomenon known as …