Conformational changes of the Tet repressor induced by tetracycline trapping
Conformational changes of the Tet repressor induced by tetracycline trapping
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DOI：
10.1006/jmbi.1998.1775
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发表时间：
1998-06-05
影响因子：
5.6
通讯作者：
Hinrichs, W
中科院分区：
文献类型：
--
作者：
Orth, P;Cordes, F;Hinrichs, W
无诱导剂的泰特阻遏物TetR的X射线晶体结构分析在2.4埃分辨率下鉴定了隧道样结合位点的两个开口之一作为诱导剂四环素-Mg 2 +[Mg Tc]（+）的入口。诱导剂的识别和结合释放构象变化，导致TetR的诱导状态。在第一步中，α-螺旋6的C-末端转角解旋，从而改变α-螺旋4的取向。α-螺旋4的这种不同取向通过一系列氢键来稳定，氢键通过八个水分子的链来介导。α-螺旋4将DNA结合结构域（α-螺旋1至3）连接到刚性TetR核心，从而通过其各自的方向调节基因表达。(C)出版社：Academic Press Limited。
The X-ray crystal structure analysis of inducer-free Tet repressor, TetR, at 2.4 Angstrom resolution identifies one of two openings of the tunnel-like binding site as the entrance for the inducer tetracycline-Mg2+, [Mg Tc](+). Recognition and binding of the inducer unleashes conformational changes leading to the induced state of TetR. In the first step, the C-terminal turn of alpha-helix 6 unwinds, thereby altering the orientation of alpha-helix 4. This different orientation of alpha-helix 4 is stabilized by a series' of hydrogen bonds mediated through a chain of eight water molecules. The alpha-helix 4 connects the DNA-binding domain (alpha-helices 1 to 3) to the rigid TetR core, and thus regulates gene expression through its respective orientations. (C) 1998 Academic Press Limited.