The amylase and maltase of Clostridium acetobutylicum.

This work concerns the degradation of starch to glucose by enzymes of Clostridium acetobutylicum, a stage in the butanol-acetone fermentation which has so far been little investigated. Previous workers have mainly used growing cultures of Cl. acetobutylicum, though Robinson (1922) showed that starch (and other carbohydrates) were fermented by toluene-treated cell suspensions. In the present work we have used cell-free enzyme preparations obtained from culture filtrates'of Cl. acetobutylicum (Weizmann). If the organism be grown in media containing maltose as the only carbohydrate, the culture filtrates contain a maltase but have no starch-splitting activity; if grown in media containing starch, culture filtrates contain both a maltase and an amylase. The properties of both these enzymes have been studied, and the amylase has been partially purified.