Interdomain Linkers Regulate Histidine Kinase Activity by Controlling Subunit Interactions.
Interdomain Linkers Regulate Histidine Kinase Activity by Controlling Subunit Interactions.
复制标题
域间连接子通过控制亚基相互作用来调节组氨酸激酶活性。
DOI：
10.1021/acs.biochem.2c00326
复制
发表时间：
2022-12-06
期刊：
影响因子：
2.9
通讯作者：
Crane, Brian R.
中科院分区：
文献类型：
--
作者：
Maschmann, Zachary;Chandrasekaran, Siddarth;Chua, Teck Khiang;Crane, Brian R.
细菌化学受体通过很大程度上未知的机制调节胞质多结构域组氨酸激酶CheA。连接P4激酶结构域与P3二聚体和P5调控结构域的肽连接物中的残基取代影响CheA的基础活性和激活。为了了解这些连接体在CheA活性中的作用，我们在Thermotoga martima (Tm) CheA变体中扩展和改变了P3-to-P4连接体（L3）和P4-to-P5连接体（L4）。CheA-LV1中L3和L4连接子的灵活延伸（连接子变体1）允许一个折叠良好的激酶结构域保留对核苷酸的野生型（WT）样结合亲和力和与受体偶联蛋白CheW的正常相互作用。然而，CheA-LV1的自磷酸化活性比WT低约50倍。含有单个P4结构域的WT和LV1二聚体都不能自磷酸化P1底物结构域。在具有扩展的L3和L4连接体的变体中，自磷酸化活性得以恢复，这些连接体有利于螺旋结构和七轴体间距。自磷酸化依赖于连接体的间距和灵活性，而不依赖于序列。使用自旋标记ATP类似物的脉冲偶极电子自旋共振（ESR）测量表明，CheA自磷酸化活性与变体二聚体中P4结构域的接近度呈负相关。尽管L3和L4连接子在一级序列和空间上分离，但它们也影响P1底物结构域的迁移性。总之，P4结构域的相互作用，由L3和L4连接体调节，影响结构域动力学和CheA的自磷酸化，从而为受体调节激酶提供了潜在的机制。
Bacterial chemoreceptors regulate the cytosolic multi-domain histidine kinase CheA through largely unknown mechanisms. Residue substitutions in the peptide linkers that connect the P4 kinase domain to the P3 dimerization and P5 regulatory domain affect CheA basal activity and activation. To understand the role that these linkers play in CheA activity, the P3-to-P4 linker (L3) and P4-to-P5 linker (L4) were extended and altered in variants of Thermotoga maritima (Tm) CheA. Flexible extensions of the L3 and L4 linkers in CheA-LV1 (linker variant 1) allowed for a well-folded kinase domain that retained wild-type (WT)-like binding affinities for nucleotide and normal interactions with the receptor-coupling protein CheW. However, CheA-LV1 autophosphorylation activity registered ~50-fold lower compared to WT. Neither a WT nor LV1 dimer containing a single P4 domain could autophosphorylate the P1 substrate domain. Autophosphorylation activity was rescued in variants with extended L3 and L4 linkers that favor helical structure and heptad spacing. Autophosphorylation depended on linker spacing and flexibility and not on sequence. Pulse-dipolar electron-spin resonance (ESR) measurements with spin-labeled ATP analogs indicated that CheA autophosphorylation activity inversely correlated with the proximity of the P4 domains within the dimers of the variants. Despite their separation in primary sequence and space, the L3 and L4 linkers also influence the mobility of the P1 substrate domains. In all, interactions of the P4 domains, as modulated by the L3 and L4 linkers, affect domain dynamics and autophosphorylation of CheA, thereby providing potential mechanisms for receptors to regulate the kinase.
登录
查看更多内容
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：
6.4
作者：
Howitt MR;Lee JY;Lertsethtakarn P;Vogelmann R;Joubert LM;Ottemann KM;Amieva MR
通讯作者：
Amieva MR
域间连接子在细菌趋化组氨酸激酶 CheA 中的调节作用
影响因子：
3.2
作者：
Ding, Xueye;He, Qiang;Wang, Xiqing
通讯作者：
Wang, Xiqing
影响因子：
5.4
作者：
Hazelbauer, Gerald L.;Lai, Wing-Cheung
通讯作者：
Lai, Wing-Cheung
影响因子：
3
作者：
Durand, Dominique;Vives, Corinne;Fieschi, Franck
通讯作者：
Fieschi, Franck