Patch-clamp characterization of the MscS-like mechanosensitive channel from Silicibacter pomeroyi.
Patch-clamp characterization of the MscS-like mechanosensitive channel from Silicibacter pomeroyi.
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波默罗氏硅杆菌 MscS 类机械敏感通道的膜片钳表征。
DOI：
10.1016/j.bpj.2013.01.055
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发表时间：
2013
影响因子：
3.4
通讯作者：
Martinac,Boris
中科院分区：
文献类型：
--
作者：
Petrov,Evgeny;Palanivelu,Dinesh;Constantine,Maryrose;Rohde,PaulR;Cox,CharlesD;Nomura,Takeshi;MinorJr,DanielL;Martinac,Boris
基于序列相似性，硫化合物分解革兰氏阴性海洋细菌Silicibacter pomeroyi的sp7基因产物MscSP属于MscS型机械敏感通道家族。为了研究MscSP通道特性，我们使用膜片钳技术在使用MJF465大肠杆菌巨型原生质球的异源表达系统（缺乏机械敏感通道MscL、MscS和MscK）上或在唑克汀脂质体中重构的纯化MscSP蛋白上测量其对膜张力的响应。这些实验显示了拉伸激活通道的典型压力依赖性门控特性，其电流/电压图表明了与E的MscS通道类似的整流行为和对阴离子的弱偏好。 然而，MscSP 通道在电导和脱敏行为方面表现出功能差异，两个通道之间最显着的差异是与 MScS 相比，MscSP 缺乏失活。这似乎是由于以下事实：尽管MscSP 在与MscS (G113) 相当的位置（该位置对失活至关重要）有一个Gly，但MscSP 在最近显示可变构影响MscS 失活的位置N117 上有一个Glu 残基而不是Asn。据我们所知，这项研究首次描述了属于硫降解α-变形菌门的海洋细菌的MscS样通道的电生理学特征。
Based on sequence similarity, the sp7 gene product, MscSP, of the sulfur-compound-decomposing Gram-negative marine bacteriumSilicibacter pomeroyibelongs to the family of MscS-type mechanosensitive channels. To investigate MscSP channel properties, we measured its response to membrane tension using the patch-clamp technique on either a heterologous expression system using giant spheroplasts of MJF465Escherichia colistrain (devoid of mechanosensitive channels MscL, MscS, and MscK), or on purified MscSP protein reconstituted in azolectin liposomes. These experiments showed typical pressure-dependent gating properties of a stretch-activated channel with a current/voltage plot indicating a rectifying behavior and weak preference for anions similar to the MscS channel ofE. coli.However, the MscSP channel exhibited functional differences with respect to conductance and desensitization behavior, with the most striking difference between the two channels being the lack of inactivation in MscSP compared with MscS. This seems to result from the fact that although MscSP has a Gly in an equivalent position to MscS (G113), a position that is critical for inactivation, MscSP has a Glu residue instead of an Asn in a position that was recently shown to allosterically influence MscS inactivation, N117. To our knowledge, this study describes the first electrophysiological characterization of an MscS-like channel from a marine bacterium belonging to sulfur-degradingα-proteobacteria.
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影响因子：
3.4
作者：
Sukharev, S
通讯作者：
Sukharev, S
影响因子：
8
作者：
Hammon, Justus;Palanivelu, Dinesh V.;Minor, Daniel L., Jr.
通讯作者：
Minor, Daniel L., Jr.
影响因子：
3.4
作者：
SUKHAREV, SI;MARTINAC, B;KUNG, C
通讯作者：
KUNG, C
影响因子：
--
作者：
Y. Saimi;Boris Martinac;Robin R. Preston;Zhou Xl;Sergei Sukharev;Paul Blount;Ching Kung
通讯作者：
Y. Saimi;Boris Martinac;Robin R. Preston;Zhou Xl;Sergei Sukharev;Paul Blount;Ching Kung
影响因子：
12.4
作者：
Naismith JH;Booth IR
通讯作者：
Booth IR