英布里斯托大学（University of Bristol）的研究人员指出，他们正在挑战一个关键的化学原理：蛋白质的存活与功能离不开水。他们的研究结果发表在这个月的Chemical Science上，最终会导致新工业酶的发展。
蛋白质是每种生物至关重要的大有机分子，能将食物转变成能量，给血液和肌肉提供氧气，驱动免疫系统。蛋白质由一个或多个多肽组成，其中多肽链则是氨基酸通过肽键缩合而成，如果加热水中蛋白质至水的沸点，这些链结构丧失，蛋白质将变性（展开）。最典型的变性例子是煮鸡蛋，此时鸡蛋中的蛋白质结构因为温度而展开，并粘附在一起成为固体。此例中的这个过程是不可逆的，但是，也有许多冷却蛋白质导致其重新折叠的例子。
以前，大家都认为水是重折叠过程所必需的，但是本研究结果表明这不是必然情况。
既然蛋白质是在水丰富环境中进化，通常认为它们的存活与功能离不开水。
科学家应用一种称为圆二色（circular dichroism）的分光镜技术，观察到携氧蛋白肌球素可在几乎完全无水分子的环境中重折叠。这些研究结果将为新工业酶的发展铺平道路，在从生物传感器发展到二氧化碳电化学还原再到液体燃料的应用中超热电阻将起关键作用。（生物谷bioon.com）
doi:10.1039/C2SC20143G
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Hyper-thermal stability and unprecedented re-folding of solvent-free liquid myoglobin
Alex Brogan, Giuliano Siligardi, Rohanah Hussain, Adam Periman, Stephen Mann
Isolating solvent effects by studying proteins in a liquid phase devoid of solvent has not been previously possible because freeze-dried protein solids do not melt but thermally degrade. Herein we circumvent this problem by modifying the interactions between myoglobin molecules via a polymer-surfactant coronal layer to produce a solvent-free liquid phase that is thermally stable over a wide temperature range. Using high-resolution synchrotron radiation circular dichroism and UV-Vis spectroscopies we determine the temperature-dependent structure and re-folding behaviour of cationized myoglobin under solvent-free conditions, and show that dehydration and subsequent melting of the nanoconstruct has no significant effect on the protein secondary structure at room temperature. Significantly, the solvent-free liquid myoglobin molecules exhibit hyper-thermophilic behaviour and can be reversibly refolded by cooling from 155°C. We attribute the abnormally high thermal stability and persistence of protein folding to entropic contributions associated with macromolecular crowding and confinement, and propose that refolding in the absence of a solvent shell is facilitated by the configurational flexibility and molecular interactivity of the polymer surfactant coronal layer.
