【摘 要】
：
Fifty protease-producing strains were screened from sediment of deep-sea cold seep,and divided into four different categories:Bacillus,Pseudoalteromonas,Vibrio,and Alteromonas according to the sequences of 16s rRNA.Their abilities to produce protease,amyl
【机 构】
：
College of Life Sciences,Qingdao University,Qingdao 266071,China;CAS Key Laboratory of Experimental
论文部分内容阅读
Fifty protease-producing strains were screened from sediment of deep-sea cold seep,and divided into four different categories:Bacillus,Pseudoalteromonas,Vibrio,and Alteromonas according to the sequences of 16s rRNA.Their abilities to produce protease,amylase,and lipase were determined,and a Bacillus strain gcc-1 displayed very strong alkaline protease activity and stability under different thermal and acidic conditions.The purification of the protease produced by strain gcc-1 was carried out by precipitation with ammonium sulfate,and sequentially chromatographed by anion exchange column and gel filtration.The purified protease showed a single band at the molecular weight of 28 kDa by SDS-PAGE.The characterization results show that the purified protease exhibited a considerable activity and stability in a wide thermal range of 10-80℃and a wide acidic range of pH 6.5-11.5,and displayed highest activity at 40℃and pH 8.5.Notably,the protease still maintained high activity even at low to 10℃.Furthermore,the protease exhibited good stability in presence of different surfactants,organic solvents,oxidizing agent H2O2,and commercial detergents.Therefore,the protease produced by gcc-1 is a cold active and high stable enzyme,and has a promising potential in laundry detergent as an additive.
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