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 ...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 supematant 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 × 10^4. Its maximum activity appears at pH 5 and 55 ℃. The chitinase is stable at pH 4.0-7.5 and below 45 ℃.展开更多
Residents of China’s capital deal with air pollution The Chinese Government has set a stringent standard for the quality of the masks being sold to combat the effects of pollution in Beijing on January 18.The news co...Residents of China’s capital deal with air pollution The Chinese Government has set a stringent standard for the quality of the masks being sold to combat the effects of pollution in Beijing on January 18.The news comes against the backdrop of the unprecedentedamount of heavy haze that had shrouded the Chinese capital for more than 20 days.展开更多
基金Projects(50621063, 50674101) supported by the National Natural Science Foundation of China
文摘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 supematant 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 × 10^4. Its maximum activity appears at pH 5 and 55 ℃. The chitinase is stable at pH 4.0-7.5 and below 45 ℃.
文摘Residents of China’s capital deal with air pollution The Chinese Government has set a stringent standard for the quality of the masks being sold to combat the effects of pollution in Beijing on January 18.The news comes against the backdrop of the unprecedentedamount of heavy haze that had shrouded the Chinese capital for more than 20 days.
