来自四棱豆种子（Psophocarpus tetragonolobus (L.) DC）的亲和纯化库尼兹型胰凝乳蛋白酶抑制剂的氨基酸序列和二硫键

Amino acid sequence and disulfide bridges of affinity purified Kunitz-type chymotrypsin inhibitor from winged bean seed (Psophocarpus tetragonolobus (L.) DC).

作者信息

Kortt A A, Burns J E, Strike P M

机构信息

CSIRO, Division of Biomolecular Engineering, Parkville Laboratory, Victoria, Australia.

出版信息

Biochem Int. 1990 Nov;22(3):543-51.

PMID:2076111

Abstract

The primary sequence of the affinity purified chymotrypsin inhibitor, WBCI, isolated from the albumin fraction of Psophocarpus tetragonolobus (L.) DC cv. UPS-122 seed was determined. The inhibitor consisted of a single polypeptide chain of 183 amino acids (Mr 20285) and the four half-cystine residues in the molecule formed two intramolecular disulfide bridges equivalent to those in other Kunitz-type seed inhibitors. The sequence of this chymotrypsin inhibitor was identical to that of chymotrypsin inhibitor-3 from cultivar UPS-31 and it showed about 50% sequence similarity to the winged bean acidic (WBTI-2, pI 5.1) and basic (WBTI-1, pI 8.9) trypsin inhibitors. Sequence similarities to other Kunitz-type seed inhibitors are discussed.

摘要

测定了从四角豆（Psophocarpus tetragonolobus (L.) DC cv. UPS-122）种子白蛋白组分中亲和纯化得到的胰凝乳蛋白酶抑制剂WBCI的一级序列。该抑制剂由一条包含183个氨基酸的单多肽链组成（Mr 20285），分子中的四个半胱氨酸残基形成了两个分子内二硫键，与其他Kunitz型种子抑制剂中的二硫键相当。这种胰凝乳蛋白酶抑制剂的序列与品种UPS-31的胰凝乳蛋白酶抑制剂-3相同，并且与四棱豆酸性（WBTI-2，pI 5.1）和碱性（WBTI-1，pI 8.9）胰蛋白酶抑制剂显示出约50%的序列相似性。讨论了与其他Kunitz型种子抑制剂的序列相似性。