英布里斯托大學（University of Bristol）的研究人員指出,，他們正在挑戰(zhàn)一個關鍵的化學原理：蛋白質(zhì)的存活與功能離不開水,。他們的研究結果發(fā)表在這個月的Chemical Science上,，最終會導致新工業(yè)酶的發(fā)展,。
蛋白質(zhì)是每種生物至關重要的大有機分子,，能將食物轉變成能量,，給血液和肌肉提供氧氣，驅(qū)動免疫系統(tǒng),。蛋白質(zhì)由一個或多個多肽組成,，其中多肽鏈則是氨基酸通過肽鍵縮合而成，如果加熱水中蛋白質(zhì)至水的沸點,，這些鏈結構喪失，蛋白質(zhì)將變性（展開）,。最典型的變性例子是煮雞蛋,，此時雞蛋中的蛋白質(zhì)結構因為溫度而展開，并粘附在一起成為固體,。此例中的這個過程是不可逆的,，但是，也有許多冷卻蛋白質(zhì)導致其重新折疊的例子,。
以前,，大家都認為水是重折疊過程所必需的，但是本研究結果表明這不是必然情況,。
既然蛋白質(zhì)是在水豐富環(huán)境中進化,，通常認為它們的存活與功能離不開水。
科學家應用一種稱為圓二色（circular dichroism）的分光鏡技術,，觀察到攜氧蛋白肌球素可在幾乎完全無水分子的環(huán)境中重折疊,。這些研究結果將為新工業(yè)酶的發(fā)展鋪平道路，在從生物傳感器發(fā)展到二氧化碳電化學還原再到液體燃料的應用中超熱電阻將起關鍵作用,。（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.
