Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
Protein Sci. 2023 Aug;32(8):e4716. doi: 10.1002/pro.4716.
The cosolvent 2,2,2-trifluoroethanol (TFE) is often used to mimic protein desiccation. We assessed the effects of TFE on cytosolic abundant heat soluble protein D (CAHS D) from tardigrades. CAHS D is a member of a unique protein class that is necessary and sufficient for tardigrades to survive desiccation. We find that the response of CAHS D to TFE depends on the concentration of both species. Dilute CAHS D remains soluble and, like most proteins exposed to TFE, gains α-helix. More concentrated solutions of CAHS D in TFE accumulate β-sheet, driving both gel formation and aggregation. At even higher TFE and CAHS D concentrations, samples phase separate without aggregation or increases in helix. Our observations show the importance of considering protein concentration when using TFE.
共溶剂 2,2,2-三氟乙醇(TFE)常用于模拟蛋白质干燥。我们评估了 TFE 对缓步动物细胞质丰富热可溶性蛋白 D(CAHS D)的影响。CAHS D 是一种独特蛋白质类别的成员,对于缓步动物的干燥生存是必要且充分的。我们发现 CAHS D 对 TFE 的响应取决于两种物质的浓度。稀释的 CAHS D 保持可溶性,并且像大多数暴露于 TFE 的蛋白质一样,获得α-螺旋。在 TFE 中更浓的 CAHS D 溶液积累β-折叠,导致凝胶形成和聚集。在更高的 TFE 和 CAHS D 浓度下,样品没有聚集或螺旋增加而相分离。我们的观察结果表明,在使用 TFE 时,考虑蛋白质浓度非常重要。