Isolation, expression and characterization of a novel dual serine protease inhibitor, OH-TCI, from king cobra venom
Isolation, expression and characterization of a novel dual serine protease inhibitor, OH-TCI, from king cobra venom
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眼镜王蛇毒液中新型双丝氨酸蛋白酶抑制剂 OH-TCI 的分离、表达和表征
DOI：
10.1016/j.peptides.2008.05.025
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发表时间：
2008-10-01
期刊：
影响因子：
3
通讯作者：
Zhang, Yun
中科院分区：
文献类型：
--
作者：
He, Ying-Ying;Liu, Shu-Bai;Zhang, Yun
蛇毒Kunitz/BPTI成员是研究丝氨酸蛋白酶及其抑制剂结构-功能关系的良好工具。通过凝胶过滤、胰蛋白酶亲和层析和反相高效液相色谱分离，从眼镜王蛇毒中分离得到一种新型Kunitz/BPTI丝氨酸蛋白酶双重抑制剂OH-TCI（trypsin- and chymotrypsin-dual inhibitor from Ophiophagus hannah）。OH-TCI由58个氨基酸残基组成，分子量为6339 Da。coli DH5 α。与Oh 11 -1相比，纯化的天然和重组OH-TCI对胰蛋白酶和胰凝乳蛋白酶都有很强的抑制活性，尽管它们之间的序列同源性很高（74.1%）。重组OH-TCI对胰蛋白酶和胰凝乳蛋白酶的抑制常数（Ki）分别为3.91 × 10（-7）和8.46 × 10（-8）M。据我们所知，Kunitz/BPTI丝氨酸蛋白酶抑制剂是第一个报道的蛇毒，具有相当的胰蛋白酶和胰凝乳蛋白酶抑制活性。(C)2008年爱思唯尔公司All rights reserved.
Snake venom Kunitz/BPTI members are good tools for understanding of structure-functional relationship between serine proteases and their inhibitors. A novel dual Kunitz/BPTI serine proteinase inhibitor named OH-TCI (trypsin- and chymotrypsin-dual inhibitor from Ophiophagus hannah) was isolated from king cobra venom by three chromatographic steps of gel filtration, trypsin affinity and reverse phase HPLC. OH-TCI is composed of 58 amino acid residues with a molecular mass of 6339 Da. Successful expression of OH-TCI was performed as the maltose-binding fusion protein in E. coli DH5 alpha . Much different from Oh11-1, the purified native and recombinant OH-TCI both had strong inhibitory activities against trypsin and chymotrypsin although the sequence identity (74.1%) between them is very high. The inhibitor constants (K-i) of recombinant OH-TCI were 3.91 x 10(-7) and 8.46 x 10(-8) M for trypsin and chymotrypsin, respectively. To our knowledge, it was the first report of Kunitz/BPTI serine proteinase inhibitor from snake venom that had equivalent trypsin and chymotrypsin inhibitory activities. (C) 2008 Elsevier Inc. All rights reserved.