NMR studies of the phosphotransfer domain of the histidine kinase CheA from Escherichia coli: assignments, secondary structure, general fold, and backbone dynamics.
NMR studies of the phosphotransfer domain of the histidine kinase CheA from Escherichia coli: assignments, secondary structure, general fold, and backbone dynamics.
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大肠杆菌组氨酸激酶 CheA 磷酸转移结构域的 NMR 研究：分配、二级结构、一般折叠和主链动力学。
DOI：
10.1021/bi00042a018
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发表时间：
1995
期刊：
影响因子：
2.9
通讯作者：
Dahlquist,FW
中科院分区：
文献类型：
--
作者：
Zhou,H;Lowry,DF;Swanson,RV;Simon,MI;Dahlquist,FW
Revised Manuscript Received August 17, 7995® abstract: Multidimensional heteronuclear NMR techniques were applied to study thephosphotransfer domain, residues 1— 134, of the histidine kinase CheA, from Escherichia coli, which containsthe site of autophosphorylation, His48. Assignments of the backbone amide groups and side chain grotons are nearly complete. Our studies show that this protein fragment consists of five a-helices (A.—£); connected by turns. Analysis of NOE distance restraints provided by two-dimensional (2D)* H—* H and three-dimensional (3D) 15N-edited NOESY spectra using model building and structure calculations indicates that the five helices form an antiparallel helix bundle with near-neighbor connectivity. The amino-terminal four helices are proposed to be arranged in a right-handed manner with helix E packing against helices C and D. From ideal hydrophobic helical packing and structure calculations, the site of autophosphorylation, His48, is nearly fully exposed to the solvent. We measured the NMR relaxation properties of the backbone 15N nuclei using inverse detected two-dimensional NMR spectroscopy. The protein backbone dynamics studies show that CheAi-134 is formedinto a tight and compact structure with very limited flexibilities both in helices and turns. Structural implications of titration and phosphorylation experiments are briefly discussed.Escherichia coli is able to respond to gradients of chemical stimuli by altering its swimming behavior to effect net migration toward attractants and away from repellents. This process is controlled by the chemotaxis system inwhich the histidine autokinase CheA plays a central role. The signal transduction cascade begins with changes inligand binding to the periplasmic domains of the membrane-spanning
