Weder J K, Haussner K
Institut für Lebensmittelchemie, Technische Universität München, Federal Republic of Germany.
Z Lebensm Unters Forsch. 1991 Oct;193(4):321-5. doi: 10.1007/BF01191627.
The reaction between the three Bowman-Birk proteinase inhibitors isolated from fenugreek seeds (TFI-B2, TFI-N2 and TFI-A8) and the human and bovine proteinases was investigated by studying the complexes formed and their properties. TFI-B2, the Lys-Leu trypsin chymotrypsin inhibitor, can bind 1.9 mol human trypsin (HT), 1.3 mol bovine trypsin (BT) and/or 0.4 mol human (HCT) or bovine (BCT) chymotrypsin per mole of inhibitor. HT was bound at the two reactive sites and BT mainly at the lysine-containing trypsin-reactive site, whereas HCT and BCT were only bound at the leucine-containing chymotrypsin-reactive site. TFI-N2, the Arg-Leu trypsin chymotrypsin inhibitor, could bind 1 mol BT and BCT, but 1.3 mol HT and 1.2 mol HCT per mole of inhibitor. In addition to the usual binding, the human enzymes could also be bound at the respective "wrong" reactive site. TFI-A8, the Arg-Arg trypsin inhibitor, binds 2 mol HT or BT per mole of inhibitor at the two trypsin-reactive sites, whereas HCT and BCT (about 0.2 mol/mol) are bound to one of the two "wrong" reactive sites.
通过研究从胡芦巴种子中分离出的三种鲍曼-伯克蛋白酶抑制剂（TFI-B2、TFI-N2和TFI-A8）与人和牛蛋白酶形成的复合物及其性质，对它们之间的反应进行了研究。TFI-B2是赖氨酸-亮氨酸胰蛋白酶糜蛋白酶抑制剂，每摩尔抑制剂可结合1.9摩尔人胰蛋白酶（HT）、1.3摩尔牛胰蛋白酶（BT）和/或0.4摩尔人（HCT）或牛（BCT）糜蛋白酶。HT结合在两个反应位点，BT主要结合在含赖氨酸的胰蛋白酶反应位点，而HCT和BCT仅结合在含亮氨酸的糜蛋白酶反应位点。TFI-N2是精氨酸-亮氨酸胰蛋白酶糜蛋白酶抑制剂，每摩尔抑制剂可结合1摩尔BT和BCT，但可结合1.3摩尔HT和1.2摩尔HCT。除了通常的结合外，人源酶还可结合在各自的“错误”反应位点。TFI-A8是精氨酸-精氨酸胰蛋白酶抑制剂，每摩尔抑制剂在两个胰蛋白酶反应位点结合2摩尔HT或BT，而HCT和BCT（约0.2摩尔/摩尔）结合在两个“错误”反应位点之一。
