STRUCTURAL VIEW OF RESPONSE REGULATOR ACTIVATION, NARL

双组分调控系统在细菌中普遍存在，为抗菌药物的开发提供了潜在的靶点。在分子水平上理解膜结合的传感器激酶如何响应输入信号进行自磷酸化，选择性地结合和磷酸化其反应调节因子，以及激活的反应调节因子随后如何引发适当的细胞功能，是工程药物干预的核心。重点关注响应调节器；我们建议通过应用高分辨率核磁共振技术来确定受体结构域磷酸化事件导致响应调节因子NarL的DNA结合结构域激活的结构机制。这将通过首先解决分离的受体和DNA结合域的结构来完成，我们已经展示了，在溶液中保持结构。我们还将确定涉及磷酸化受体结构域、将靶DNA结合到DNA结合结构域以及在trans中添加两个结构域的结构变化。我们的最终目标将是比较完整的核磁共振结构的静息状态和活性状态的全长NarL。

Two-component regulatory systems are ubiquitous in bacteria and offer potential targets for the development of antibacterial drugs. A molecular level understanding of how a membrane bound sensor kinase autophosphorylates in response to an input signal, selectively binds and phosphorylates its response regulator, and the activated response regulator subsequently elicits the appropriate cellular function, is central to engineering pharmaceutical interventions. Focusing on the response regulator; we propose to determine the structural mechanism by which the event of receiver domain phosphorylation results in the activation of the DNA binding domain of the response regulator NarL through the application of high resolution NMR techniques. This will be accomplished by first solving the structures of the isolated receiver and DNA binding domains which we have shown, remain structured in solution. We will also determine the structural changes involved in phosphorylating the receiver domain, binding target DNA to the DNA binding domain, and adding the two domains in trans. Our ultimate goal will be to compare the complete NMR structures of the resting state and the active state of full length NarL.