Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
Proc Natl Acad Sci U S A. 2010 Oct 5;107(40):17101-6. doi: 10.1073/pnas.1011569107. Epub 2010 Sep 20.
Water-protein interactions dictate many processes crucial to protein function including folding, dynamics, interactions with other biomolecules, and enzymatic catalysis. Here we examine the effect of surface fluorination on water-protein interactions. Modification of designed coiled-coil proteins by incorporation of 5,5,5-trifluoroleucine or (4S)-2-amino-4-methylhexanoic acid enables systematic examination of the effects of side-chain volume and fluorination on solvation dynamics. Using ultrafast fluorescence spectroscopy, we find that fluorinated side chains exert electrostatic drag on neighboring water molecules, slowing water motion at the protein surface.
水-蛋白质相互作用决定了许多对蛋白质功能至关重要的过程，包括折叠、动力学、与其他生物分子的相互作用以及酶催化。在这里，我们研究了表面氟化对水-蛋白质相互作用的影响。通过在设计的螺旋蛋白中掺入 5,5,5-三氟亮氨酸或（4S）-2-氨基-4-甲基己酸来修饰，可以系统地研究侧链体积和氟化对溶剂化动力学的影响。使用超快荧光光谱法，我们发现氟化侧链对相邻水分子施加静电力拖曳，从而减慢蛋白质表面的水分子运动。
