The conducting form of gramicidin A is a right handed double-stranded double helix
The conducting form of gramicidin A is a right handed double-stranded double helix
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DOI：
10.1073/pnas.95.22.12950
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发表时间：
1998-10-27
影响因子：
11.1
通讯作者：
Duax, WL
中科院分区：
文献类型：
--
作者：
Burkhart, BM;Li, N;Duax, WL
线性十五肽抗生素，甘草素D，是短杆菌的天然产物，已知在合成和天然膜中形成离子通道。本文报道的右旋双链双螺旋二聚体(DSDHR)的X-射线晶体结构与N-15-核磁共振和CD数据相一致，表明脂双层中具有功能的甘草素D通道。这些结构展示了通过通道的单文件离子转移。结果还表明，以前关于Cs+和K+盐络合物中的左旋双链双螺旋二聚体的晶体结构报道可能是错误的，我们的证据表明DSDHR是负责离子在膜中传输的主要构象。
The linear pentadecapeptide antibiotic, gramicidin D, is a naturally occurring product of Bacillus brevis known to form ion channels in synthetic and natural membranes. The x-ray crystal structures of the right-handed double-stranded double-helical dimers (DSDHR) reported here agree with N-15-NMR and CD data on the functional gramicidin D channel in lipid bilayers. These structures demonstrate single-file ion transfer through the channels. The results also indicate that previous crystal structure reports of a left-handed double-stranded double-helical dimer in complex with Cs+ and K+ salts may be in error and that our evidence points to the DSDHR as the major conformer responsible for ion transport in membranes.