Rahfeld J, Schierhorn M, Hartrodt B, Neubert K, Heins J
Martin-Luther-University, Biotechnikum Halle, F.R.G.
Biochim Biophys Acta. 1991 Jan 29;1076(2):314-6. doi: 10.1016/0167-4838(91)90284-7.
Dipeptidyl peptidase IV preferably hydrolyzes peptides and proteins with a penultimate proline residue. Umezawa and co-workers (Umezawa et al. (1984) J. Antibiotics 37, 422-425) reported that diprotin A (Ile-Pro-Ile) and diprotin B (Val-Pro-Leu) are inhibitors for dipeptidyl peptidase IV. We could show that both compounds as well as other tripeptides with a penultimate proline residue are substrates for dipeptidyl peptidase IV. An apparent competitive inhibition by those compounds is a kinetic artifact due to the substrate-like structure of such tripeptides.
二肽基肽酶IV优先水解具有倒数第二个脯氨酸残基的肽和蛋白质。梅泽及其同事（梅泽等人，（1984年）《抗生素杂志》37卷，422 - 425页）报道，双蛋白A（异亮氨酸 - 脯氨酸 - 异亮氨酸）和双蛋白B（缬氨酸 - 脯氨酸 - 亮氨酸）是二肽基肽酶IV的抑制剂。我们能够证明，这两种化合物以及其他具有倒数第二个脯氨酸残基的三肽都是二肽基肽酶IV的底物。这些化合物的明显竞争性抑制是由于此类三肽具有类似底物的结构而产生的动力学假象。
