Yi G S, Park C B, Kim S C, Cheong C
Magnetic Resonance Group, Korea Basic Science Institute, Taejon, South Korea.
FEBS Lett. 1996 Nov 25;398(1):87-90. doi: 10.1016/s0014-5793(96)01193-3.
The structure of 21-residue antimicrobial peptide buforin II has been determined by using NMR spectroscopy and restrained molecular dynamics. Buforin II adopts a flexible random structure in H2O. In trifluoroethanol (TFE)/H2O (1:1, v/v) mixture, however, buforin II assumes a regular alpha-helix between residues Val12 and Arg20 and a distorted helical structure between residues Gly7 and Pro11. The model structure obtained shows an amphipathic character in the region from Arg5 to the C-terminus, Lys21. Like other known cationic antimicrobial peptides, the amphipathic structure might be the key factor for antimicrobial activity of buforin II.
利用核磁共振光谱和受限分子动力学方法确定了21个氨基酸残基的抗菌肽蟾蜍灵II的结构。蟾蜍灵II在水中呈灵活的无规结构。然而，在三氟乙醇（TFE）/水（1:1，v/v）混合物中，蟾蜍灵II在Val12和Arg20残基之间呈现规则的α螺旋结构，在Gly7和Pro11残基之间呈现扭曲的螺旋结构。所获得的模型结构在从Arg5到C末端Lys21的区域显示出两亲性特征。与其他已知的阳离子抗菌肽一样，两亲性结构可能是蟾蜍灵II抗菌活性的关键因素。
