Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, USA.
J Am Chem Soc. 2013 Apr 17;135(15):5477-92. doi: 10.1021/ja3088407. Epub 2013 Apr 2.
Interactions among β-sheets occur widely in protein quaternary structure, protein-protein interaction, and protein aggregation and are central in Alzheimer's and other amyloid-related diseases. This Perspective looks at the structural biology of these important yet under-appreciated interactions from a supramolecular chemist's point of view. Common themes in the supramolecular interactions of β-sheets are identified and richly illustrated though examples from proteins, amyloids, and chemical model systems. β-Sheets interact through edge-to-edge hydrogen bonding to form extended layers and through face-to-face hydrophobic or van der Waals interactions to form layered sandwich-like structures. Side chains from adjacent layers can fit together through simple hydrophobic contacts or can participate in complementary interdigitation or knob-hole interactions. The layers can be aligned, offset, or rotated. The right-handed twist of β-sheets provides additional opportunities for stabilization of edge-to-edge contacts and rotated layered structures.
β-折叠片之间的相互作用广泛存在于蛋白质四级结构、蛋白质-蛋白质相互作用和蛋白质聚集物中，并且在阿尔茨海默病和其他与淀粉样蛋白相关的疾病中起着核心作用。本文从超分子化学家的角度来看待这些重要但未被充分认识的相互作用的结构生物学。通过蛋白质、淀粉样蛋白和化学模型系统的例子，确定了β-折叠片的超分子相互作用的共同主题，并进行了丰富的说明。β-折叠片通过边缘到边缘的氢键相互作用形成扩展层，通过面对面的疏水或范德华相互作用形成层状三明治样结构。相邻层的侧链可以通过简单的疏水接触相互配合，也可以参与互补的交错或扣孔相互作用。层可以对齐、偏移或旋转。β-折叠片的右手扭曲为边缘到边缘的接触和旋转层状结构提供了额外的稳定机会。
