Kapitannikov Iu V, Iavashev L P, Ginodman L M, Antonov V K
Bioorg Khim. 1983 Feb;9(2):228-31.
Oxygen exchange in the amide group of leucine amide catalyzed by leucine aminopeptidase, and in leucyltyrosine amide catalyzed by porcine pepsin, was found to proceed mainly by the transfer of the leucyl residue onto the ammonia or tyrosine amide which are formed during the hydrolysis. Thus oxygen exchange in the non-hydrolyzed substrate can not be a proof of the tetrahedral intermediate formation in the course of the catalysis by proteolytic enzymes.
亮氨酸氨肽酶催化的亮氨酸酰胺酰胺基团中的氧交换，以及猪胃蛋白酶催化的亮氨酰酪氨酸酰胺中的氧交换，被发现主要是通过亮氨酰残基转移到水解过程中形成的氨或酪氨酸酰胺上进行的。因此，未水解底物中的氧交换不能作为蛋白水解酶催化过程中四面体中间体形成的证据。
