1a6i: Difference between revisions
No edit summary |
No edit summary |
||
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
The X-ray crystal structure analysis of inducer-free Tet repressor, TetR, at 2.4 A resolution identifies one of two openings of the tunnel-like | The X-ray crystal structure analysis of inducer-free Tet repressor, TetR, at 2.4 A 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. | ||
==About this Structure== | ==About this Structure== | ||
| Line 23: | Line 23: | ||
[[Category: transcription regulation]] | [[Category: transcription regulation]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:41:24 2008'' | ||
Revision as of 12:41, 21 February 2008
|
TET REPRESSOR, CLASS D VARIANT
OverviewOverview
The X-ray crystal structure analysis of inducer-free Tet repressor, TetR, at 2.4 A 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.
About this StructureAbout this Structure
1A6I is a Single protein structure of sequence from Escherichia coli. Known structural/functional Site: . Full crystallographic information is available from OCA.
ReferenceReference
Conformational changes of the Tet repressor induced by tetracycline trapping., Orth P, Cordes F, Schnappinger D, Hillen W, Saenger W, Hinrichs W, J Mol Biol. 1998 Jun 5;279(2):439-47. PMID:9642048
Page seeded by OCA on Thu Feb 21 11:41:24 2008