Structure of the membraneous fumarate sensor DcuS from Escherichia coli

双组分调控系统代表了细菌中最普遍的跨膜信号系统。这些系统的传感器由质周配体结合域、跨膜螺旋和细胞质组氨酸蛋白激酶组成。没有关于配体结合和转导跨膜螺旋的结构信息。在前期工作中，已鉴定出大肠杆菌的富马酸盐传感器dcu，并利用核磁共振光谱对其配体结合域进行了结构研究。完成了二维结构，显示为a3ba2b3结构，并确定了富马酸结合区。本文将研究配体结合结构和膜积分结构域的结构。了解这两个区域的结构和结构变化对配体结合的响应将有助于理解信号在膜内的感知和传递。结构和功能研究依赖于液体和固体核磁共振波谱结合体内和体外的分子生物学和生化方法。

Two-component regulatory systems represent the most prevalent systems for transmembrane signalling in bacteria. The sensors of these systems consist of a periplasmic ligand binding domain, transmembrane helices and cytoplasmic histidine protein kinases. No structural information on the ligand binding and the transducing transmembrane helices is available. In preparatory work a fumarate sensor DcuS of Escherichia coli has been identified and structural studies of the ligand binding domain have been started by NMR spectroscopy. The two dimensional structure is finished and shows an a3ba2b3 structure, and the fumarate binding region was identified. In the proposal the structure of the ligand binding and of the membrane integral domains will be studied. Understanding the structures and structural changes in both domains in response to ligand binding will help to understand signal preception and transmission into and across the membrane. The structural and functional studies rely on liquid and solid state NMR spectroscopy in combination with molecular biological and biochemical methods in vivo and in vitro.