Maeda K, Wakabayashi S, Matsubara H
J Biochem. 1983 Sep;94(3):865-70. doi: 10.1093/oxfordjournals.jbchem.a134429.
An alpha-amylase inhibitor (0.53-inhibitor) was digested with pepsin and the cystine-containing peptides were isolated by SP-Sephadex C-25 column chromatography and high voltage paper electrophoresis. Amino acid compositions and partial sequences of these peptides and amino acid compositions of the peptides separated after performic acid oxidation revealed the presence of 4 disulfide bonds in the inhibitor. They were formed between residues 6 and 115, 20 and either 41 or 42, 99 and either 41 or 42, and 28 and 83. The disulfide bond partners of residues 20 and 99 were not conclusively determined because of the difficulty of cleavage of the Cys-Cys bond at residues 41 and 42. Among 9 cysteines in this inhibitor Cys-54 must be in a free form, since no evidence was obtained for its contribution to disulfide bond formation.
一种α-淀粉酶抑制剂（0.53-抑制剂）用胃蛋白酶消化，含胱氨酸的肽通过SP-葡聚糖凝胶C-25柱色谱和高压纸电泳分离。这些肽的氨基酸组成和部分序列以及过甲酸氧化后分离的肽的氨基酸组成表明该抑制剂中存在4个二硫键。它们形成于第6位和第115位、第20位与第41位或第42位、第99位与第41位或第42位以及第28位和第83位残基之间。由于在第41位和第42位残基处难以裂解半胱氨酸-半胱氨酸键，第20位和第99位残基的二硫键配对尚未最终确定。在该抑制剂的9个半胱氨酸中，半胱氨酸-54必定以游离形式存在，因为没有证据表明它参与二硫键的形成。
