Purification and characterization of extracellular chitinase from a novel strain Aspergillus fumigatus CS01

Central South University School of Resources Processing and Bioengineering Changsha 410083 China
Journal of Central South University of Technology (Impact Factor: 0.36). 08/2009; 16(4):552-557. DOI: 10.1007/s11771-009-0092-5


Twelve samples derived from different locations in south central area of China are treated by enrichment and spread-plate
technique for initial screening. Seven chitinase-producing strains are isolated. The chitinase present in the culture supernatant
of strain CS-01 possesses the maximum activity of 0.118 U/mL. Analysis of the morphological feature and the ITS rDNA sequence
reveals that strain CS-01 belongs to Aspergillus fumigatus. Production of the chitinase is regulated by a inducible way and the maximum activity appears at 36 h in colloidal chitin
culture. Purification of the chitinase is carried out by salting out, gel filtrate chromatography and anion exchange chromatography
sequentially. Native-PAGE and SDS-PAGE indicate that the chitinase from A. fumigatus CS-01 is a monomer with the relative molecular mass estimated to be 4.50×104. Its maximum activity appears at pH 5 and 55 °C. The chitinase is stable at pH 4.0–7.5 and below 45 °C.

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