title: Purification and characterization of a cold alkaline protease from a psychrophilic Pseudomonas aeruginosa HY1215.
abstract: A novel alkaline protease was purified from Pseudomonas aeruginosa HY1215 using ammonium sulfate, DEAE-Sepharose and Sephacryl S-200 gel filtration chromatographic techniques. The protease had a relative molecular weight of 32.8 KDa by SDS-PAGE, and the optimal temperature and pH for excellent stability and activity were determined as 25 °C and 10.0, respectively. Within the pH range of 7.0-11.0, the protease had a good stability, which could retain more than 80 % of its original activity; in the temperature range of 15-35 °C, the protease had a higher activity, and its activity at 20 °C could amount to 85 % of the maximum activity at 25 °C. Besides, the enzyme activity showed a valuable stability towards several commercially available surfactants (Tween-80, Tween-40, and Triton X-100) and bleaches (H2O2) even when their concentrations ranged up to 2.0 and 1.6 %.
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, People's Republic of China.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Hao
authors.forename: Mi
authors.initials: M
authors.lastname: Sun
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D002850:Chromatography, Gel; D004795:Enzyme Stability; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008666:Metalloendopeptidases / Q000737:chemistry* / Q000302:isolation & purification; D008970:Molecular Weight; D017830:Octoxynol / Q000737:chemistry; D011136:Polysorbates / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000737:chemistry / Q000201:enzymology* / Q000254:growth & development; D013501:Surface-Active Agents / Q000737:chemistry; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D011136:Polysorbates; D013501:Surface-Active Agents; D017830:Octoxynol; D006861:Hydrogen Peroxide; D008666:Metalloendopeptidases; C110245:cold alkaline protease; C068430:polysorbate 40