Bacterial chemoreceptor signaling complexes control kinase activity by stabilizing the catalytic domain of CheA.
Bacterial chemoreceptor signaling complexes control kinase activity by stabilizing the catalytic domain of CheA.
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DOI：
10.1073/pnas.2218467120
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发表时间：
2023-08-08
影响因子：
11.1
通讯作者：
Thompson, Lynmarie K.
中科院分区：
文献类型：
--
作者：
Tran, Thomas;Mudiyanselage, Aruni P. K. K. Karunanayake;Eyles, Stephen J.;Thompson, Lynmarie K.
组氨酸激酶调节许多双组分信号通路，使细菌能够感知和响应其环境。在细菌的趋化系统中，传感发生在跨膜化学感受器结合到两个细胞质蛋白，组氨酸激酶CheA，和耦合蛋白CheW的大信号复合物。CheA在化学感受器复合物中如何调节仍然是一个关键问题。我们采用氢氘交换质谱法来测量功能复合物内大肠杆菌CheA的信号相关变化，并证明CheA的催化结构域的稳定化是激酶激活的关键步骤。由于趋化性对许多细菌的毒力至关重要，因此了解CheA激酶激活的机制有助于抗生素的生产。能动细菌有一个趋化系统，使它们能够感知环境，并将它们的游泳引向有利的条件。趋化性涉及一个信号传导过程，其中配体结合到化学受体的胞外结构域改变组氨酸激酶CheA的活性，CheA结合到受体的远端细胞质尖端约300 nm处，以启动控制鞭毛旋转的磷酸化级联反应。受体的胞质结构域被认为是通过动力学和/或稳定性的变化来传播这种信号，但目前还不清楚这些变化如何调节CheA的激酶活性。为了解决这个问题，我们已经使用氢氘交换质谱法来探测大肠杆菌天冬氨酸受体胞质片段，CheA和CheW的功能信号复合物内的CheA的结构和动力学。我们的研究结果表明，稳定的P4催化结构域的CheA与激酶活化。此外，在感觉适应过程中发生的激酶的激活的差异依赖于受体的不稳定化的P3二聚化结构域的CheA。最后，带有磷酸化组氨酸的P1结构域的氢交换性质鉴定了CheA二聚体中P1/P1'的二聚体界面，并支持有序的催化顺序结合机制，其中二聚体P1/P1'仅在核苷酸结合时与P4具有生产性相互作用。因此，稳定/不稳定的结构域是一个关键要素的机制，调节CheA激酶活性的趋化性，并可能发挥作用，在控制其他激酶。
Histidine kinases regulate numerous two-component signaling pathways that enable bacteria to sense and respond to their environment. In the bacterial chemotaxis system, sensing occurs in large signaling complexes of transmembrane chemoreceptors bound to two cytoplasmic proteins, the histidine kinase CheA, and the coupling protein CheW. How CheA is regulated within chemoreceptor complexes remains a key question. We employ hydrogen deuterium exchange mass spectrometry to measure signaling-related changes of Escherichia coli CheA within functional complexes and demonstrate that stabilization of the catalytic domain of CheA is a key step in kinase activation. Because chemotaxis is critical to the virulence of many bacteria, understanding the mechanism of CheA kinase activation could aid in the production of antibiotics. Motile bacteria have a chemotaxis system that enables them to sense their environment and direct their swimming toward favorable conditions. Chemotaxis involves a signaling process in which ligand binding to the extracellular domain of the chemoreceptor alters the activity of the histidine kinase, CheA, bound ~300 Å away to the distal cytoplasmic tip of the receptor, to initiate a phosphorylation cascade that controls flagellar rotation. The cytoplasmic domain of the receptor is thought to propagate this signal via changes in dynamics and/or stability, but it is unclear how these changes modulate the kinase activity of CheA. To address this question, we have used hydrogen deuterium exchange mass spectrometry to probe the structure and dynamics of CheA within functional signaling complexes of the Escherichia coli aspartate receptor cytoplasmic fragment, CheA, and CheW. Our results reveal that stabilization of the P4 catalytic domain of CheA correlates with kinase activation. Furthermore, differences in activation of the kinase that occur during sensory adaptation depend on receptor destabilization of the P3 dimerization domain of CheA. Finally, hydrogen exchange properties of the P1 domain that bears the phosphorylated histidine identify the dimer interface of P1/P1’ in the CheA dimer and support an ordered sequential binding mechanism of catalysis, in which dimeric P1/P1’ has productive interactions with P4 only upon nucleotide binding. Thus stabilization/destabilization of domains is a key element of the mechanism of modulating CheA kinase activity in chemotaxis, and may play a role in the control of other kinases.
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影响因子：
15
作者：
Wang, Xiqing;Wu, Chun;Anh Vu, Joan-Emma Shea;Dahlquist, Frederick W.
通讯作者：
Dahlquist, Frederick W.
影响因子：
3.6
作者：
Briegel A;Ames P;Gumbart JC;Oikonomou CM;Parkinson JS;Jensen GJ
通讯作者：
Jensen GJ
影响因子：
2.9
作者：
Haglin ER;Yang W;Briegel A;Thompson LK
通讯作者：
Thompson LK
影响因子：
2.9
作者：
Briegel A;Wong ML;Hodges HL;Oikonomou CM;Piasta KN;Harris MJ;Fowler DJ;Thompson LK;Falke JJ;Kiessling LL;Jensen GJ
通讯作者：
Jensen GJ
影响因子：
6.4
作者：
Huang, Zhou;Wang, Yun-Hao;Liu, Shuang-Jiang
通讯作者：
Liu, Shuang-Jiang