【摘要】 用Ｎ－溴代丁烯二酰亚胺修饰小麦巯基蛋白酶抑制剂（ＣＰＩ），计算出ＣＰＩ分子内有一个色氨酸残基被修饰，修饰的ＣＰＩ对木瓜蛋白酶的抑制活性全部丧失，表明色氨酸对ＣＰＩ的活性非常重要，是分子保持抑制活性所必需的；用Ｎ－乙基顺丁烯二酰亚胺修饰ＣＰＩ分子的巯基，计算出ＣＰＩ分子中含有１７个巯基，这些巯基被修饰后，ＣＰＩ仍保持１００％的抑制活性；用二硫苏糖醇和碘乙酸处理小麦ＣＰＩ分子内的巯基后，其抑制活性无变化，表明ＣＰＩ的抑制活性不需巯基参与。用小麦ＣＰＩ对赤霉病菌的生长进行抑制实验，结果表明，小麦ＣＰＩ对赤霉病菌的生长有强抑制作用，当ＣＰＩ的用量为４０μｇ时（即０．３０８ｎｍｏｌ／Ｌ），就可对赤霉菌发生抑制作用。更多还原

【Abstract】 Tryptophan(Trp) in cysteine proteinase inhibitor(CPI) from wheat seed was modified with N Bromosuccinimide(NBS). The data showed that there is one Trp in CPI, the modified CPI lost its inhibitory activity on papain completely.The CPI kept all its activity of inhibition when its sulfhydryl group was modified with N Ethylmaleimide(NEM), dithiothreitol(DTT) and iodoacetic acid. In CPI there are 17 sulfhydryl groups which are not essential for its inhibitory activity. The CPI from wheat seed strongly inhibited the growth of Gibberella zeae, at the concentration of 3.08×10 -9 mol/L.更多还原