Membrane permeabilization mechanisms of a cyclic antimicrobial peptide, tachyplesin I, and its linear analog
Membrane permeabilization mechanisms of a cyclic antimicrobial peptide, tachyplesin I, and its linear analog
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DOI：
10.1021/bi970588v
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发表时间：
1997-08-12
期刊：
影响因子：
2.9
通讯作者：
Anzai, K
中科院分区：
文献类型：
--
作者：
Matsuzaki, K;Yoneyama, S;Anzai, K
河豚毒素I(Tachyplesin I，T-SS)是一种由两个二硫键组成的环状抗平行β-折叠结构。该多肽能有效地渗透细菌膜和人造脂膜。T-ACM是一种由乙酰胺甲基保护的具有四个SH基团的线性类似肽，尽管脂组织受到更大的破坏，但显示出更弱的膜通透活性[Matsuzaki，K.，Nakayama，M.，Fukui，M.，Otaka，A.，Funakoshi，S.，Fujii，N.，Bessho，K.，&Miyajima，K.(1993年)生化32,11704-11710]。为了阐明T-SS的有效渗透机制，我们研究了这两种多肽与脂质体和平面脂双层的相互作用。能够跨越双层(约3 nm长)的环肽形成了一个阴离子选择性的孔，并与孔的形成耦合在双层上转移。与顺式正电位相比，顺式负跨膜电位更有利于孔道的形成。相反，线状多肽没有发生移位。相反，它通过破坏脂类组织和囊泡的形态变化来损害膜屏障。
Tachyplesin I (T-SS), an antimicrobial peptide from Tachypleus tridentatus, has a cyclic antiparallel beta-sheet structure maintained by two disulfide bridges. The peptide effectively permeabilizes both bacterial and artificial lipid membranes. T-Acm, a linear analog peptide with the four SH groups protected by acetamidomethyl groups, exhibits a much weaker membrane-permeabilizing activity in spite of a greater disruption of the lipid organization [Matsuzaki, K., Nakayama, M., Fukui, M., Otaka, A., Funakoshi, S., Fujii, N., Bessho, K., & Miyajima, K. (1993) Biochemistry 32, 11704-11710]. To clarify the efficient permeabilization mechanism of T-SS, we studied the interactions of both peptides with liposomes and planar lipid bilayers. The cyclic peptide capable of spanning the bilayer (ca. 3 nm length) was found to form an anion-selective pore and translocate across the bilayer coupled with the pore formation. A cis-negative transmembrane potential facilitated the pore formation compared with the cis-positive potential. In contrast, the linear peptide failed to translocate. Instead, it impaired the membrane barrier by disrupting the lipid organization with morphological changes in the vesicles.