Gerisch S, Ullmann G, Stubenrauch K, Jakubke H D
University of Leipzig, Faculty of Biosciences, Pharmacy and Psychology, Institute of Biochemistry, Germany.
Biol Chem Hoppe Seyler. 1994 Dec;375(12):825-8.
The alpha-chymotrypsin (EC 3.4.21.1)-catalyzed reaction of Mal-Phe-OMe with H-Leu-NH2 has been studied under a range of reaction conditions, for example various cryogenic reagents for shock-freezing, addition of dimethyl sulfoxide (DMSO) and decreased reaction temperatures down to 213 K. It has been shown that the peptide yield is independent of the method of shock-freezing. The optimal reaction temperature was between 263 K and 248 K. Lower temperatures result in clearly retarded reactions. Addition of DMSO leads to decreasing peptide yields. It is certain that the peptide bond formation is catalyzed by the active enzyme, since unspecific protein surface catalysis gave no peptide yields at all.
在一系列反应条件下,研究了α-胰凝乳蛋白酶(EC 3.4.21.1)催化丙氨酰-苯丙氨酸甲酯(Mal-Phe-OMe)与亮氨酰-氨(H-Leu-NH2)的反应,例如使用各种低温试剂进行快速冷冻、添加二甲基亚砜(DMSO)以及将反应温度降至213 K。结果表明,肽产率与快速冷冻方法无关。最佳反应温度在263 K至248 K之间。较低的温度会导致反应明显延迟。添加DMSO会导致肽产率降低。可以确定肽键的形成是由活性酶催化的,因为非特异性蛋白质表面催化根本不会产生肽产率。