Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany.
Department of Chemistry and Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL 60637, USA.
Science. 2017 May 19;356(6339):753-756. doi: 10.1126/science.aaf6846.
Hydrotropes are small molecules that solubilize hydrophobic molecules in aqueous solutions. Typically, hydrotropes are amphiphilic molecules and differ from classical surfactants in that they have low cooperativity of aggregation and work at molar concentrations. Here, we show that adenosine triphosphate (ATP) has properties of a biological hydrotrope. It can both prevent the formation of and dissolve previously formed protein aggregates. This chemical property is manifested at physiological concentrations between 5 and 10 millimolar. Therefore, in addition to being an energy source for biological reactions, for which micromolar concentrations are sufficient, we propose that millimolar concentrations of ATP may act to keep proteins soluble. This may in part explain why ATP is maintained in such high concentrations in cells.
水增溶物是小分子，可以将疏水分子溶解于水溶液中。通常情况下，水增溶物是两亲分子，与经典表面活性剂不同，它们的聚集协同性低，并且在摩尔浓度下工作。在这里，我们表明三磷酸腺苷（ATP）具有生物水增溶物的特性。它既能防止蛋白质聚集体的形成，也能溶解已经形成的蛋白质聚集体。这种化学性质在生理浓度 5 到 10 毫摩尔之间表现出来。因此，除了作为生物反应的能量源（对于这种反应，微摩尔浓度就足够了）之外，我们还提出，毫摩尔浓度的 ATP 可能会使蛋白质保持溶解状态。这部分解释了为什么细胞中会维持如此高浓度的 ATP。
