Receptor-ligand bonds strengthened by tensile mechanical force are referred to as catch bonds. This review examines experimental data and biophysical theory to analyze why mechanical force prolongs the lifetime of these bonds rather than shortens the lifetime by pulling the ligand out of the binding pocket. Although many mathematical models can explain catch bonds, experiments using structural variants have been more helpful in determining how catch bonds work. The underlying mechanism has been worked out so far only for the bacterial adhesive protein FimH. This protein forms catch bonds because it is allosterically activated when mechanical force pulls an inhibitory domain away from the ligand-binding domain. Other catch bond-forming proteins, including blood cell adhesion proteins called selectins and the motor protein myosin, show evidence of allosteric regulation between two domains, but it remains unclear if this is related to their catch bond behavior.

中文翻译：

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捕获键的生物物理学。

通过拉伸机械力增强的受体-配体键被称为捕获键。本文综述了实验数据和生物物理理论，以分析为什么机械力会延长这些键的寿命，而不是通过将配体从结合袋中拉出而缩短寿命。尽管许多数学模型可以解释捕获键，但是使用结构变体的实验对于确定捕获键的工作方式更为有用。到目前为止，仅针对细菌粘附蛋白FimH才研究了潜在的机制。该蛋白质形成捕获键，因为当机械力将抑制域从配体结合域拉开时，它被变构激活。其他形成捕获键的蛋白质，包括称为选择素的血细胞粘附蛋白和运动蛋白肌球蛋白，