New World Institute of Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
Appl Biochem Biotechnol. 2010 Oct;162(3):733-43. doi: 10.1007/s12010-009-8841-3. Epub 2009 Nov 20.
An extracellular lipase secreted by Pseudomonas aeruginosa CS-2 was purified to homogeneity about 25.5-fold with an overall yield of 45.5%. The molecular mass of the lipase was estimated to be 33.9 kDa by SDS-PAGE and 36 kDa by gel filtration. The optimum temperature and pH were 50 degrees C and 8.0. The lipase was found to be stable at pH 4-10 and below 50 degrees C. Its hydrolytic activity was highest against p-nitrophenyl palmitate (p-NPP) among p-nitrophenyl esters of fatty acids with various chain lengths. The lipase was activated in the presence of Ca(2+), while it was inactivated by other metal ions more or less. EDTA significantly reduced the lipase activity, indicating the lipase was a metalloenzyme. Gum Arabic and polyvinyl alcohol 124 enhanced lipase activity but Tween-20, Tween-80, and hexadecyltrimethyl ammonium bromide strongly inhibited the lipase. It exhibited stability in some organic solvents. The lipase was activated in the presence of acetonitrile. Conversely, it was drastically inactivated by methanol and ethanol.
铜绿假单胞菌 CS-2 分泌的胞外脂肪酶经 SDS-PAGE 约纯化 25.5 倍，总体产率为 45.5%。脂肪酶的分子量通过 SDS-PAGE 估计为 33.9 kDa，通过凝胶过滤估计为 36 kDa。最适温度和 pH 值分别为 50°C 和 8.0。该脂肪酶在 pH 值为 4-10 和 50°C 以下时稳定。其水解活性在各种链长的脂肪酸对硝基苯酯中对 p-硝基苯棕榈酸酯 (p-NPP) 最高。该脂肪酶在 Ca(2+) 存在下被激活，而在其他金属离子存在下或多或少被失活。EDTA 显著降低脂肪酶活性，表明脂肪酶是一种金属酶。阿拉伯胶和聚乙烯醇 124 增强脂肪酶活性，但吐温-20、吐温-80 和十六烷基三甲基溴化铵强烈抑制脂肪酶。它在一些有机溶剂中表现出稳定性。脂肪酶在乙腈存在下被激活。相反，甲醇和乙醇使其严重失活。
