Identification Of A Chitinase-producing Bacterial Strain, Characterization, Gene Cloning And Expression Of The Chitinase

Chitinase (Ec.3.2.14), a group of enzymes capable of degrading chitin directly to chitin oligosaccharides or N-acetylglucosamine, are produced by a wide variety of organisms including plants, microorganism and animals, and contribute to many physiological reaction. Chitinase have received increased attention because of their potential application in biocontrol of plant-pathogenic fungi and pests, as well as in bioconversion of shellfish chitin wastes.In order to develop the potential of chitinase-producing microorganisms as biocontrol agents for insect pests, the chitin from maggot and pupae was used to isolate chitinase-producing microorganisms. Fifty one chitinase-producing strains were isolated from soil samples, and bacterium C4 was at last isolated from these strains by oral bioassay because of its apparently higher mortality rate to locusts than that of others. In addition, histopathologic study was carried out by examining midget tissues of locusts infected with C4. Observation of the midguts at 12 h after infection revealed that the chitin-containing peritrophic membrane (PM) of midguts was disrupted, and at 48 h after infection, the epithetlial cells of midguts began to display...