 A strain of "Clostridium" can convert nearly any form of cellulose into butanol even in the presence of oxygen.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".