Step toward Probing the Nonannular Belt of Membrane Proteins.
Step toward Probing the Nonannular Belt of Membrane Proteins.
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DOI：
10.1021/acs.analchem.2c02811
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发表时间：
2022-10-11
影响因子：
7.4
通讯作者：
Laganowsky, Arthur
中科院分区：
文献类型：
--
作者：
Kumar, Smriti;Zhu, Yun;Stover, Lauren;Laganowsky, Arthur
整合膜蛋白嵌入在生物膜中，在那里它们进行许多生物过程。虽然存在于膜中的脂质对于膜蛋白功能是至关重要的，但是仍然难以表征许多脂质与膜蛋白的结合事件，例如形成环带的那些。在这里，我们使用天然质谱沿着的电荷减少性能的三甲基胺N-氧化物（TMAO），以表征大量的脂质结合事件的细菌氨通道（AmtB）。在没有TMAO的情况下，观察到相邻电荷状态之间的显著峰重叠，导致不同分子种类的错误丰度。随着TMAO的加入，加权平均电荷态（Zavg）降低。此外，附近电荷状态之间的间距增加使得能够观察到更高数量的脂质结合物质，同时使质谱峰重叠最小化。这些条件帮助我们确定了多达16个脂质结合事件的平衡结合常数（Kd）。前几个脂质结合事件的结合常数显示最高的亲和力，而较高的脂质结合事件的结合常数收敛到一个类似的值。这些发现表明AmtB的脂质结合从非环状转变为环状。
Integral membrane proteins are embedded in the biological membrane where they carry out numerous biological processes. Although lipids present in the membrane are crucial for membrane protein function, it remains difficult to characterize many lipid binding events to membrane proteins, such as those that form the annular belt. Here we use native mass spectrometry along with the charge reducing properties of trimethylamine N-oxide (TMAO) to characterize a large number of lipid binding events to the bacterial ammonia channel (AmtB). In the absence of TMAO, significant peak overlap between neighboring charge states is observed, resulting in erroneous abundances for different molecular species. With the addition of TMAO, the weighted average charge state (Zavg) was decreased. In addition, the increased spacing between nearby charge states enabled a higher number of lipid binding species to be observed while minimizing mass spectral peak overlap. These conditions helped us to determine the equilibrium binding constants (Kd) for up to 16 lipid binding events. The binding constants for the first few lipid binding events display the highest affinity, whereas the binding constants for higher lipid binding events converge to a similar value. These findings suggest a transition from non-annular to annular lipid binding to AmtB.
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完整膜蛋白复合物的质谱法。
影响因子：
14.8
作者：
通讯作者：
--
影响因子：
16.6
作者：
Cong X;Liu Y;Liu W;Liang X;Laganowsky A
通讯作者：
Laganowsky A
影响因子：
5.7
作者：
Gault，Joseph;Lianoudaki，Danai;Landreh，Michael
通讯作者：
Landreh，Michael
影响因子：
15
作者：
Cong, Xiao;Liu, Yang;Laganowsky, Arthur
通讯作者：
Laganowsky, Arthur
DOI：
10.1073/pnas.1303888110
发表时间：
2013-06-11
影响因子：
11.1
作者：
Marcoux, Julien;Wang, Sheila C.;Robinson, Carol V.
通讯作者：
Robinson, Carol V.