Analysis of SARS-CoV E protein ion channel activity by tuning the protein and lipid charge.
Analysis of SARS-CoV E protein ion channel activity by tuning the protein and lipid charge.
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DOI：
10.1016/j.bbamem.2013.05.008
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发表时间：
2013-09
期刊：
影响因子：
--
通讯作者：
Aguilella VM
中科院分区：
文献类型：
--
作者：
Verdiá-Báguena C;Nieto-Torres JL;Alcaraz A;Dediego ML;Enjuanes L;Aguilella VM
以前曾报道过SARS冠状病毒（CoV）包膜(E)蛋白形成的离子通道的部分特征（C. Verdiá-Báguena等人，2012）。在此，我们在三个系列实验的基础上，对脂质参与冠状病毒E蛋白通道的结构和功能提供了新的重要见解。首先，在广泛的pH范围内的逆转电位测量允许分离来自蛋白质跨膜结构域的可电离残基和来自二phytanoyl磷脂酰丝氨酸（DPhPS）脂质的负电荷基团对通道选择性的贡献。相应的有效pka值与酸渣候选物的模型pka值一致。其次，通道电导随盐浓度的变化揭示了两种不同的模式（donnan控制的电扩散和块状电扩散），这与选择性实验的结果完全一致。第三，通过测量中性二phytanoyl磷脂酰胆碱（DPhPC）脂质和负电荷DPhPS脂质在低盐浓度和高盐浓度下的混合物中的通道电导，我们得出结论，在带电脂质和中性脂质中，通道中的蛋白质-脂质构象可能是相同的。总的来说，整套实验支持SARS-CoV E通道的蛋白脂质结构，并解释了中性膜和带电膜之间观察到的通道电导的巨大差异。通过调节脂质电荷分析SARS-CoV E蛋白通道结构。蛋白质脂质通道构象在带电脂质和中性脂质中是相似的。脂质电荷的电导调节是双相的。
A partial characterization of the ion channels formed by the SARS coronavirus (CoV) envelope (E) protein was previously reported (C. Verdiá-Báguena et al., 2012). Here, we provide new significant insights on the involvement of lipids in the structure and function of the CoV E protein channel on the basis of three series of experiments. First, reversal potential measurements over a wide range of pH allow the dissection of the contributions to channel selectivity coming from ionizable residues of the protein transmembrane domain and also from the negatively charged groups of diphytanoyl phosphatidylserine (DPhPS) lipid. The corresponding effective pKas are consistent with the model pKas of the acidic residue candidates for titration. Second, the change of channel conductance with salt concentration reveals two distinct regimes (Donnan-controlled electrodiffusion and bulk-like electrodiffusion) fully compatible with the outcomes of selectivity experiments. Third, by measuring channel conductance in mixtures of neutral diphytanoyl phosphatidylcholine (DPhPC) lipids and negatively charged DPhPS lipids in low and high salt concentrations we conclude that the protein–lipid conformation in the channel is likely the same in charged and neutral lipids. Overall, the whole set of experiments supports the proteolipidic structure of SARS-CoV E channels and explains the large difference in channel conductance observed between neutral and charged membranes. SARS-CoV E protein channel structure is analyzed by tuning lipid charge. Proteolipidic channel conformation is similar in charged and neutral lipids. Lipid charge modulation of conductance is biphasic.
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影响因子：
3.7
作者：
Nieto-Torres JL;Dediego ML;Alvarez E;Jiménez-Guardeño JM;Regla-Nava JA;Llorente M;Kremer L;Shuo S;Enjuanes L
通讯作者：
Enjuanes L
影响因子：
3.4
作者：
Alcaraz, A;Nestorovich, EM;Bezrukov, SM
通讯作者：
Bezrukov, SM
影响因子：
3.4
作者：
Lee, MT;Hung, WC;Huang, HW
通讯作者：
Huang, HW
影响因子：
6.7
作者：
Pervushin K;Tan E;Parthasarathy K;Lin X;Jiang FL;Yu D;Vararattanavech A;Soong TW;Liu DX;Torres J
通讯作者：
Torres J
影响因子：
2.4
作者：
RAYMOND, L;SLATIN, SL;FINKELSTEIN, A
通讯作者：
FINKELSTEIN, A