The Isolation and Mode of Action of a Bacterial Glucanosyltranferase

A glucanosyltransferase has been obtained in a high state of purity from a bacterium of the Bacillus group. The enzyme is distinct from the other carbohydrases produced by the organism. The pH optimum for the transferase is 5, and the molecular weight is in the range of 70,000 to 80,000. The transferase is stable at low temperatures but is rapidly inactivated at elevated temperatures. The new enzyme effects a transfer of glucanosyl segments from maltopentaose, higher molecular weight maltohomologues or starch to maltopentaose, and other maltohomologues to yield new oligosaccharides. The transferase may be of importance in the metabolism of starch in the bacterium.