2f23
From Proteopedia
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| , resolution 1.60Å | |||||||
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| Gene: | gfh1 (Thermus thermophilus) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of GreA factor homolog 1 (Gfh1) protein of Thermus thermophilus
Overview
Gfh1, a transcription factor from Thermus thermophilus, inhibits all catalytic activities of RNA polymerase (RNAP). We characterized the Gfh1 structure, function and possible mechanism of action and regulation. Gfh1 inhibits RNAP by competing with NTPs for coordinating the active site Mg2+ ion. This coordination requires at least two aspartates at the tip of the Gfh1 N-terminal coiled-coil domain (NTD). The overall structure of Gfh1 is similar to that of the Escherichia coli transcript cleavage factor GreA, except for the flipped orientation of the C-terminal domain (CTD). We show that depending on pH, Gfh1-CTD exists in two alternative orientations. At pH above 7, it assumes an inactive 'flipped' orientation seen in the structure, which prevents Gfh1 from binding to RNAP. At lower pH, Gfh1-CTD switches to an active 'Gre-like' orientation, which enables Gfh1 to bind to and inhibit RNAP.
About this Structure
2F23 is a Single protein structure of sequence from Thermus thermophilus. Full crystallographic information is available from OCA.
Reference
pH-dependent conformational switch activates the inhibitor of transcription elongation., Laptenko O, Kim SS, Lee J, Starodubtseva M, Cava F, Berenguer J, Kong XP, Borukhov S, EMBO J. 2006 May 17;25(10):2131-41. Epub 2006 Apr 20. PMID:16628221
Page seeded by OCA on Thu Mar 20 16:47:08 2008
