施氏假单胞菌中不同细胞组分的脂肪酶合成活性研究

Study of the Synthetic Activity of Lipase from Different Cell Components in Pseudomonas stutzeri

摘要:

本文以具有高合成活性的施氏假单胞菌为研究目标，采用超声破碎-溶剂提取等方法分离制备各细胞组分的粗脂肪酶，以非水介质中的合成活性为表征指标，测定了在非水介质中不同条件下各细胞组分粗脂肪酶的活性变化。研究发现，施氏假单胞菌的细胞质、细胞膜和细胞壁均含有合成反应活性的脂肪酶，且各合成活性在全细胞中所占的比例分别为47.25%、22.70%和30.05%。各细胞组分脂肪酶催化反应平衡时间高于全细胞催化反应平衡时间。当培养时间为48 h和以大豆油为诱导剂时，各细胞组分的脂肪酶获得最大的合成活性。根据上述研究结果，建立了具有合成活性的脂肪酶在施氏假单胞菌中的生产模型。本研究对深入揭示以施氏假单胞菌为代表的全细胞催化剂的催化机理，促进高效全细胞生物催化剂的研发和应用均具有重要的参考意义。

Abstract:

Using Pseudomonas stutzeri cells with synthetic activity, the crude lipases in different cell components were separated and obtained by ultrasonic destruction-solvent extraction, and the changes in the activities of lipases in different cell components under different conditions were determined. The results showed that the lipases with synthetic activity were localized in the cytoplasm, cell membrane, and cell wall of P. stutzeri cells, and the proportions of the corresponding synthetic activities in the whole cell were 47.25%, 22.70%, and 30.05%, respectively. The equilibrium time of the transesterification reaction catalyzed by lipases in the different components was higher than that for whole-cell catalysis. The lipases from different components showed the highest synthetic activity when the culture time was 48 h and soybean oil was used as the inducer. Based on the above study results, a production model of lipases in P. stutzeri cells was established. These results provide an important reference revealing the catalytic mechanism of whole-cell catalysis using P. stutzeri as a representative organism, and could promote the development and application of high-efficiency whole-cell biocatalysts.