某些植物、昆蟲和動物制造抗凍蛋白從而在冰點以下的溫度中生存，一項研究幫助解釋了某些最強大的天然抗凍蛋白如何工作。Konrad Meister及其同事把他們的研究重點放在了火紅色的加拿大擬步甲蟲（Dendroides canadensis）上,，這種甲蟲的過冬幼蟲會制造超活性的抗凍蛋白。這組作者使用一種稱為太赫茲光譜的技術在分子水平上觀察了這種幼蟲的蛋白和水的動態(tài),。此前的分析已經確定了這些蛋白可以與冰晶體結合,，降低這些晶體能夠生長的最低溫度。這組作者報告說,，當水過量存在的時候,，這種抗凍活性能夠持續(xù)下去，這是由于被認為抑制了冰的形成的氫鍵結合的大范圍延遲,。此前的研究也發(fā)現了諸如雪蚤等其他一些生物制造具有不同生化結構的抗凍蛋白,。這組作者提出,，這兩種截然不同的機制以不同的比例賦予了至少3大類抗凍蛋白的活性，這些抗凍蛋白是由某些昆蟲,、細菌,、極地魚類和其他能抵御極端寒冷的生物制造的。這組作者說,，進化已經產生了兩種在結構上有差別的解決方案從而幫助生物在冰點以下溫度中生存,。(生物谷Bioon.com)

doi: 10.1073/pnas.1214911110
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Long-range protein–water dynamics in hyperactive insect antifreeze proteins

Konrad Meistera, Simon Ebbinghausa, Yao Xub, John G. Dumanc, Arthur DeVriesd, Martin Gruebelee, David M. Leitnerb, and Martina Havenitha,1

Antifreeze proteins (AFPs) are specific proteins that are able to lower the freezing point of aqueous solutions relative to the melting point. Hyperactive AFPs, identified in insects, have an especially high ability to depress the freezing point by far exceeding the abilities of other AFPs. In previous studies, we postulated that the activity of AFPs can be attributed to two distinct molecular mechanisms: (i) short-range direct interaction of the protein surface with the growing ice face and (ii) long-range interaction by protein-induced water dynamics extending up to 20 Å from the protein surface. In the present paper, we combine terahertz spectroscopy and molecular simulations to prove that long-range protein–water interactions make essential contributions to the high antifreeze activity of insect AFPs from the beetle Dendroides canadensis. We also support our hypothesis by studying the effect of the addition of the osmolyte sodium citrate.