Abstract
The release of intracellular pullulanase (IP) of Aerobacter aerogenes was investigated to study the production mechanism of extracellular pullulanase (EP). A factor, named inductive effector (IE), which released IP from the cells was found in the culture broth of EP production. For IE formation, an initial medium pH of 9.0 was suitable, and the desirable culture period was 4 days. The IE fraction (Mw < 500, free of pullulanase activity) was purified from the supernatant of the culture broth by ultrafiltration and ion exchange resins. IE acted on living cells of A. aerogenes and released intracellular protease from the cells in shaking cultivation. Cell-bound pullulanase may be released by the proteases. Commercial endoproteases and lysozyme helped to make IP release, however, the mode of their action differed from that of IE.
