荞麦种子中蛋白酶抑制剂BWI-4a的完整氨基酸序列。

Complete amino acid sequence of the protease inhibitor BWI-4a from buckwheat seeds.

作者信息

Belozersky M A, Dunaevsky Y E, Musolyamov A K, Egorov T A

机构信息

Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119899, Russia.

出版信息

Biochemistry (Mosc). 2000 Oct;65(10):1140-4.

PMID:11092956

Abstract

The complete amino acid sequence of the protease inhibitor BWI-4a from buckwheat (Fagopyrum esculentum Moench) seeds has been established by automated Edman degradation in combination with MALDI-TOF mass spectrometry. The inhibitor molecule consists of 67 amino acid residues with a single disulfide bond. Its N-terminus is blocked by a pyroglutamic acid residue. The reactive site of the inhibitor contains an Arg43-Asp44 bond. Mass spectrometry revealed that inhibitor BWI-4a is present in buckwheat seeds in two isoforms differing by a single amino acid substitution of Gly40 for Ala40. Analysis of the amino acid sequence of the BWI-4a inhibitor indicates that this inhibitor is a member of the potato proteinase inhibitor I family.

摘要

通过自动埃德曼降解结合基质辅助激光解吸电离飞行时间质谱法，已确定了来自荞麦（苦荞麦）种子的蛋白酶抑制剂BWI-4a的完整氨基酸序列。该抑制剂分子由67个氨基酸残基组成，含有一个二硫键。其N端被一个焦谷氨酸残基封闭。抑制剂的活性位点包含一个Arg43-Asp44键。质谱分析表明，抑制剂BWI-4a在荞麦种子中以两种亚型存在，二者仅在第40位氨基酸处存在Gly40被Ala40取代的差异。对BWI-4a抑制剂氨基酸序列的分析表明，该抑制剂是马铃薯蛋白酶抑制剂I家族的成员。