INDUCTION AND PURIFICATION OF TWO EXTRACELLULAR CHITINASES FROM BEAUVERIA BASS1ANA
球孢白僵菌两种胞外几丁质酶的诱导和纯化

Chitinases were induced when Beauveria bassiana CH-1316,a UV mutagenic mutant strain, was first grown in a complete medium to pre-logarithmic growth phase and then transferred to a medium containing colloidal chitin as a sole carbon and nitrogen source. Culture filtrates were collected about 20-25h after transferring, and this just occurred at the logarithmic growth phase and the peak time of chitinase activities. Two extracellular chitinases were purified to homogeneous by (NH4)2SO4 precipitation, DEAE-cellulose chromatography and gel filtration. Chitinase 1 showed mixed activities of endo-and exo-chitinase,while chitinase 2 was an endo-chitinase. The molecular weight of two chitinases were determined to be 52 000 and 39 000 by gel filtration.