Zaks A, Klibanov A M
Proc Natl Acad Sci U S A. 1985 May;82(10):3192-6. doi: 10.1073/pnas.82.10.3192.
Three different lipases (porcine pancreatic, yeast, and mold) can vigorously act as catalysts in a number of nearly anhydrous organic solvents. Various transesterification reactions catalyzed by porcine pancreatic lipase in hexane obey Michaelis-Menten kinetics. The dependence of the catalytic activity of the enzyme in organic media on the pH of the aqueous solution from which it was recovered is bell-shaped, with the maximum coinciding with the pH optimum of the enzymatic activity in water. The catalytic power exhibited by the lipases in organic solvents is comparable to that displayed in water. In addition to transesterification, lipases can catalyze several other processes in organic media including esterification, aminolysis, acyl exchange, thiotransesterification, and oximolysis; some of these reactions proceed to an appreciable extent only in nonaqueous solvents.
三种不同的脂肪酶(猪胰脂肪酶、酵母脂肪酶和霉菌脂肪酶)能在多种几乎无水的有机溶剂中有力地充当催化剂。猪胰脂肪酶在己烷中催化的各种酯交换反应遵循米氏动力学。该酶在有机介质中的催化活性对其回收所用水溶液pH的依赖性呈钟形,最大值与该酶在水中的活性最适pH一致。脂肪酶在有机溶剂中展现出的催化能力与在水中相当。除酯交换反应外,脂肪酶还能在有机介质中催化其他几种反应,包括酯化、氨解、酰基交换、硫代酯交换和肟解反应;其中一些反应仅在非水溶剂中能进行到可观的程度。