Protons Are Fast and Smart; Proteins Are Slow and Dumb: On the Relationship of Electrospray Ionization Charge States and Conformations.
Protons Are Fast and Smart; Proteins Are Slow and Dumb: On the Relationship of Electrospray Ionization Charge States and Conformations.
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质子又快又聪明；蛋白质又慢又哑：论电喷雾电离电荷态与构象的关系。
DOI：
10.1021/jasms.1c00100
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发表时间：
2021-07-07
影响因子：
3.2
通讯作者：
Clemmer, David E.
中科院分区：
文献类型：
--
作者：
Raab, Shannon A.;El-Baba, Tarick J.;Laganowsky, Arthur;Russell, David H.;Valentine, Stephen J.;Clemmer, David E.
我们提出了简单的考虑，即质子运动的时间尺度的差异，最轻和最快的化学部分，以及与蛋白质动力学相关的更长的时间尺度，在最重和最慢的分析物中，如何允许许多来自溶液的蛋白质构象在电喷雾蛋白质溶液进入气相的过程中被动力学捕获。在溶液中，质子的量子性质导致它们通过隧道效应改变位置，这是一个瞬时的过程；此外，格洛特斯机制表明，这些小颗粒可以几乎瞬时地对发生在更长时间尺度上的蛋白质的动态运动做出反应。构象变化伴随着体系自由能的有利或不利变化，为溶剂↔蛋白质质子交换提供了动力。因此，当蛋白质构象的热分布相互转换时，质子化状态迅速响应，因为特定的酸性和碱性部位暴露或受到保护。在质谱计的真空中，质子被固定在特定于它们被结合的蛋白质构象的位置。通过这种方式，溶液中的构象状态在电喷雾进入气相时得以保留。这些想法与电喷雾质谱学对改变溶液中蛋白质结构的局部环境的微小变化的精致敏感性是一致的。对于溶液中蛋白质的质子化，我们可能还记得这个近似值，口语化的表述是--质子又快又聪明；蛋白质又慢又傻。
We present simple considerations of how differences in time scales of motions of protons, the lightest and fastest chemical moiety, and the much longer time scales associated with the dynamics of proteins, among the heaviest and slowest analytes, may allow many protein conformations from solution to be kinetically trapped during the process of electrospraying protein solutions into the gas phase. In solution, the quantum nature of protons leads them to change locations by tunneling, an instantaneous process; moreover, the Grotthuss mechanism suggests that these small particles can respond nearly instantaneously to the dynamic motions of proteins that occur on much longer time scales. A conformational change is accompanied by favorable or unfavorable variations in the free energy of the system, providing the impetus for solvent ↔ protein proton exchange. Thus, as thermal distributions of protein conformations interconvert, protonation states rapidly respond, as specific acidic and basic sites are exposed or protected. In the vacuum of the mass spectrometer, protons become immobilized in locations that are specific to the protein conformations from which they were incorporated. In this way, conformational states from solution are preserved upon electrospraying them into the gas phase. These ideas are consistent with the exquisite sensitivity of electrospray mass spectra to small changes of the local environment that alter protein structure in solution. We might remember this approximation for the protonation of proteins in solution with the colloquial expression—protons are fast and smart; proteins are slow and dumb.
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影响因子：
2.9
作者：
ANDERSON, DE;BECKTEL, WJ;DAHLQUIST, FW
通讯作者：
DAHLQUIST, FW
影响因子：
7.4
作者：
Benesch, JLP;Sobott, F;Robinson, CV
通讯作者：
Robinson, CV
DOI：
10.1073/pnas.96.13.7232
发表时间：
1999-06-22
影响因子：
11.1
作者：
Clarke, DT;Doig, AJ;Jones, GR
通讯作者：
Jones, GR
影响因子：
7.4
作者：
Daub, Christopher D.;Cann, Natalie M.
通讯作者：
Cann, Natalie M.
影响因子：
4.6
作者：
Chen EH;Lu TT;Hsu JC;Tseng YJ;Lim TS;Chen RP
通讯作者：
Chen RP