Theoretical aspects of the biological catch bond.
Theoretical aspects of the biological catch bond.
复制标题
生物捕获键的理论方面。
DOI：
10.1021/ar800202z
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发表时间：
2009
影响因子：
18.3
通讯作者：
Y. Pereverzev
中科院分区：
文献类型：
--
作者：
O. Prezhdo;Y. Pereverzev
生物捕获键是迷人的和违反直觉的。当在体内或体外对捕获结合施加外力时，结合抵抗断裂并且反而变得更强。相比之下，代表绝大多数生物和化学键的普通滑动键在受到力时解离得更快。捕获键行为在20年前首次被理论预测，最近在许多蛋白质受体-配体复合物中被实验观察到。在这个帐户中，我们回顾了最简单的物理化学模型，导致债券寿命的解析表达式，实验数据的简洁的通用表示，并捕获绑定的明确要求。这种现象有许多表现形式：随着不断增长的恒定力而增加的寿命是其定义特征。如果力随时间增加，如在跳跃斜坡实验中，捕获结合在键断裂力的概率密度中产生额外的最大值。新的最大值发生在比滑移约束最大值更小的力处，在类似于相变的过程中以一定的斜坡率与后者合并。如果力是周期性施加的，就像在血液流动中一样，捕捉键的性质强烈地依赖于力的频率。捕获结合的结果从受体-配体相互作用的复杂景观。如果力（i）阻止通过天然途径的解离并驱动系统越过更高的能量势垒或（ii）以加强受体-配体结合的方式改变蛋白质构象，则键寿命可以增加。键变形可能与变构有关;蛋白质一端的力诱导的构象变化传播到另一端的结合位点。周围的水创造了更令人兴奋的效果。蛋白质-水张力提供了一个额外的屏障，其可以负责在相对于零力的低力下观察到的键寿命的显著下降。这种对弱蛋白质-水相互作用的键性质的强烈依赖可能在许多生物系统中提供通用的激活机制，并创造新类型的捕获结合。分子动力学模拟提供了原子的见解：键离解的分子观点为理论模型提供了基础，并区分了实验数据的不同解释。已知的捕获键的数量正在增长;例如，在酶催化、肽通过纳米孔的移位、DNA解旋、化学键的光诱导解离和散装材料的负热膨胀中发现了类似物。更精细的武力解决方案可能会提供更多。理解捕获键的性质提供了对生物系统在一般外部扰动下的行为的深入了解。
The biological catch bond is fascinating and counterintuitive. When an external force is applied to a catch bond, either in vivo or in vitro, the bond resists breaking and becomes stronger instead. In contrast, ordinary slip bonds, which represent the vast majority of biological and chemical bonds, dissociate faster when subjected to a force. Catch-bond behavior was first predicted theoretically 20 years ago and has recently been experimentally observed in a number of protein receptor-ligand complexes. In this Account, we review the simplest physical-chemical models that lead to analytic expressions for bond lifetime, the concise universal representations of experimental data, and the explicit requirements for catch binding. The phenomenon has many manifestations: increased lifetime with growing constant force is its defining characteristic. If force increases with time, as in jump-ramp experiments, catch binding creates an additional maximum in the probability density of bond rupture force. The new maximum occurs at smaller forces than the slip-binding maximum, merging with the latter at a certain ramp rate in a process resembling a phase transition. If force is applied periodically, as in blood flows, catch-bond properties strongly depend on force frequency. Catch binding results from a complex landscape of receptor-ligand interactions. Bond lifetime can increase if force (i) prevents dissociation through the native pathway and drives the system over a higher energy barrier or (ii) alters protein conformations in a way that strengthens receptor-ligand binding. The bond deformations can be associated with allostery; force-induced conformational changes at one end of the protein propagate to the binding site at the other end. Surrounding water creates further exciting effects. Protein-water tension provides an additional barrier that can be responsible for significant drops in bond lifetimes observed at low forces relative to zero force. This strong dependence of bond properties on weak protein-water interactions may provide universal activation mechanisms in many biological systems and create new types of catch binding. Molecular dynamics simulations provide atomistic insights: the molecular view of bond dissociation gives a foundation for theoretical models and differentiates between alternative interpretations of experimental data. The number of known catch bonds is growing; analogs are found in enzyme catalysis, peptide translocation through nanopores, DNA unwinding, photoinduced dissociation of chemical bonds, and negative thermal expansion of bulk materials, for example. Finer force resolution will likely provide many more. Understanding the properties of catch bonds offers insight into the behavior of biological systems subjected to external perturbations in general.
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影响因子：
15.9
作者：
Yago, Tadayuki;Lou, Jizhong;Zhu, Cheng
通讯作者：
Zhu, Cheng
DOI：
10.1073/pnas.0601255103
发表时间：
2006-06-27
影响因子：
11.1
作者：
Guo, Bin;Guilford, William H.
通讯作者：
Guilford, William H.
DOI：
10.1073/pnas.0401870101
发表时间：
2004-08-03
影响因子：
11.1
作者：
Evans, E;Leung, A;Zhu, C
通讯作者：
Zhu, C
影响因子：
3.4
作者：
Marshall, BT;Sarangapani, KK;Zhu, C
通讯作者：
Zhu, C
影响因子：
6.1
作者：
Hong, Jing;Chen, Tao-tao;Wang, Shao-yun
通讯作者：
Wang, Shao-yun