Joubert F J, Kruger H, Townshend G S, Botes D P
Eur J Biochem. 1979 Jun;97(1):85-91. doi: 10.1111/j.1432-1033.1979.tb13088.x.
The Macrotyloma axillare plant, belonging to the Leguminosae family, is a perennial climbing or trailing herb 0.2--3.5 m long. The plant is indigenous to South Africa and it occurs in the warm dry northern parts of the Transvaal. It has been introduced into Australia, where the seed are used as animal food. Two protease inhibitors, DE-3 and DE-4, were purified from Macrotyloma axillare seed by gel filtration on Sephadex G-50 followed by ion-exchange chromatography on DEAE-cellulose. They each comprise 76 amino acid residues including 14 half-cystine residues. The complete primary structures of the two protease innibitors have been elucidated and their sequences are 67% identical. The inhibitor specificities, the sequences, the invariant amino acid residues and the reactive inhibitor sites of protease inhibitors DE-3 and DE-4 resemble the corresponding properties of the Bowman-Birk double-headed protease inhibitor group. The cysteine residues are in similar locations to those in protease inhibitors of known structure so they are presumed to link similarly.
腋生大翼豆（Macrotyloma axillare）植物属于豆科，是一种多年生攀缘或蔓生草本植物，长0.2 - 3.5米。该植物原产于南非，生长在德兰士瓦省温暖干燥的北部地区。它已被引入澳大利亚，其种子被用作动物饲料。通过在葡聚糖凝胶G - 50上进行凝胶过滤，随后在DEAE - 纤维素上进行离子交换色谱法，从腋生大翼豆种子中纯化出两种蛋白酶抑制剂DE - 3和DE - 4。它们各自包含76个氨基酸残基，其中包括14个半胱氨酸残基。已经阐明了这两种蛋白酶抑制剂的完整一级结构，并且它们的序列有67%是相同的。蛋白酶抑制剂DE - 3和DE - 4的抑制剂特异性、序列、不变氨基酸残基以及反应性抑制剂位点类似于鲍曼 - 伯克双头蛋白酶抑制剂组的相应特性。半胱氨酸残基的位置与已知结构的蛋白酶抑制剂中的位置相似，因此推测它们的连接方式也相似。
