Konstantinovsky Daniel, Perets Ethan A, Santiago Ty, Velarde Luis, Hammes-Schiffer Sharon, Yan Elsa C Y
Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, United States.
ACS Cent Sci. 2022 Oct 26;8(10):1404-1414. doi: 10.1021/acscentsci.2c00702. Epub 2022 Sep 6.
Understanding the role of water in biological processes remains a central challenge in the life sciences. Water structures in hydration shells of biomolecules are difficult to study due to overwhelming background from aqueous environments. Biological interfaces introduce additional complexity because biomolecular hydration differs at interfaces compared to bulk solution. Here, we perform experimental and computational studies of chiral sum frequency generation (chiral SFG) spectroscopy to probe chirality transfer from a protein to the surrounding water molecules. This work reveals that chiral SFG probes the first hydration shell around the protein almost exclusively. We explain the selectivity to the first hydration shell in terms of the asymmetry induced by the protein structure and specific protein-water hydrogen-bonding interactions. This work establishes chiral SFG as a powerful technique for studying hydration shell structures around biomolecules at interfaces, presenting new possibilities to address grand research challenges in biology, including the molecular origins of life.
理解水在生物过程中的作用仍然是生命科学中的一项核心挑战。由于来自水性环境的压倒性背景，生物分子水合壳中的水结构很难研究。生物界面引入了额外的复杂性，因为与本体溶液相比，生物分子在界面处的水合作用有所不同。在这里，我们对手性和频产生（chiral SFG）光谱进行了实验和计算研究，以探测从蛋白质到手性水分子的手性转移。这项工作表明，手性SFG几乎专门探测蛋白质周围的第一个水合壳。我们根据蛋白质结构和特定的蛋白质-水氢键相互作用所诱导的不对称性来解释对第一个水合壳的选择性。这项工作将手性SFG确立为研究界面处生物分子周围水合壳结构的一种强大技术，为应对生物学中的重大研究挑战（包括生命的分子起源）提供了新的可能性。
