马氏钳蝎短链神经毒素BmP03的溶液结构的NMR研究

BmP03为从马氏钳蝎中得到的具有钾离子通道阻断活性的短链神经毒素。应用2DNMR实验和分子模拟技术，进行BmP03的溶液结构计算，结果显示BmP03与从蝎毒中得到的其他短链神经毒素具有相似结构。含一个α-螺旋(Cys3-Gly12)，两条反平行的β-折叠股(Asn16-Cys19,Cys24-Asn27)。螺旋与折叠股间靠3对二硫键相连，在Asp20到Val23间形成一个二型转角结构。根据BmP03的溶液结构，对其表面电荷对钾离子通道阻断活性的影响进行观察。

Three-dimensional structure of BmP03 from venom of scorpion buthus martensii karsch

From the venom of scorpion Buthus martensii Karsch, a short peptide (BmP03, 28 amino acid residues) was isolated, characterized and tested as a weak inhibitor of K^+ channel. In this paper, the solution structure of BmP03 was determined by 2D ^1H NMR spectroscopy and molecular modeling calculations. The conformation of BmP03 is composed of a short α-helix (Cys3-Gly12) and a two-strand antiparallel β-sheet (Asn16-Cys19, Cys24-Asn27). There are three disulfide bridges (Cys3-Cys19, Cys6-Cys24, Cys10-cys26) connecting the α-helix and β-sheet. Asp20 to Val23 residues form a type Ⅱ turn linking the two strands. Structural and electrostatic potential comparison between BmP03 and its analogues were also presented.