 A strain of "Clostridium cellulolyticum", a native cellulose-degrading microbe, affords isobutanol directly from cellulose.A combination of succinate and ethanol can be fermented to produce butyrate (a precursor to butanol fuel) by utilizing the metabolic pathways present in "Clostridium kluyveri".Succinate is an intermediate of the TCA cycle, which metabolizes glucose.