1p6q
From Proteopedia
Line 1: | Line 1: | ||
[[Image:1p6q.jpg|left|200px]] | [[Image:1p6q.jpg|left|200px]] | ||
- | + | <!-- | |
- | + | The line below this paragraph, containing "STRUCTURE_1p6q", creates the "Structure Box" on the page. | |
- | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
- | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
- | | | + | or leave the SCENE parameter empty for the default display. |
- | | | + | --> |
- | + | {{STRUCTURE_1p6q| PDB=1p6q | SCENE= }} | |
- | + | ||
- | + | ||
- | }} | + | |
'''NMR Structure of the Response regulator CheY2 from Sinorhizobium meliloti, complexed with Mg++''' | '''NMR Structure of the Response regulator CheY2 from Sinorhizobium meliloti, complexed with Mg++''' | ||
Line 31: | Line 28: | ||
[[Category: Scharf, B.]] | [[Category: Scharf, B.]] | ||
[[Category: Schmitt, R.]] | [[Category: Schmitt, R.]] | ||
- | [[Category: | + | [[Category: Chemotaxis]] |
- | [[Category: | + | [[Category: Chey2]] |
- | [[Category: | + | [[Category: Response regulator]] |
- | [[Category: | + | [[Category: Signal transduction]] |
- | [[Category: | + | [[Category: Sinorhizobium meliloti]] |
- | [[Category: | + | [[Category: Spine]] |
- | [[Category: | + | [[Category: Structural genomic]] |
- | [[Category: | + | [[Category: Structural proteomics in europe]] |
- | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Apr 13 08:09:13 2008'' | |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun | + |
Revision as of 05:09, 13 April 2008
NMR Structure of the Response regulator CheY2 from Sinorhizobium meliloti, complexed with Mg++
Overview
The chemotactic signalling chain to the flagellar motor of Sinorhizobium meliloti features a new type of response regulator, CheY2. CheY2 activated by phosphorylation (CheY2-P) controls the rotary speed of the flagellar motor (instead of reversing the sense of rotation), and it is efficiently dephosphorylated by phospho-retrotransfer to the cognate kinase, CheA. Here, we report the NMR solution structures of the Mg(2+)-complex of inactive CheY2, and of activated CheY2-BeF(3), a stable analogue of CheY2-P, to an overall root mean square deviation of 0.042 nm and 0.027 nm, respectively. The 14 kDa CheY2 protein exhibits a characteristic open (alpha/beta)(5) conformation. Modification of CheY2 by BeF(3)(-) leads to large conformational changes of the protein, which are in the limits of error identical with those observed by phosphorylation of the active-centre residue Asp58. In BeF(3)-activated CheY2, the position of Thr88-OH favours the formation of a hydrogen bond with the active site, Asp58-BeF(3), similar to BeF(3)-activated CheY from Escherichia coli. In contrast to E.coli, this reorientation is not involved in a Tyr-Thr-coupling mechanism, that propagates the signal from the incoming phosphoryl group to the C-terminally located FliM-binding surface. Rather, a rearrangement of the Phe59 side-chain to interact with Ile86-Leu95-Val96 along with a displacement of alpha4 towards beta5 is stabilised in S.meliloti. The resulting, activation-induced, compact alpha4-beta5-alpha5 surface forms a unique binding domain suited for specific interaction with and signalling to a rotary motor that requires a gradual speed control. We propose that these new features of response regulator activation, compared to other two-component systems, are the key for the observed unique phosphorylation, dephosphorylation and motor control mechanisms in S.meliloti.
About this Structure
1P6Q is a Single protein structure of sequence from Sinorhizobium meliloti. Full crystallographic information is available from OCA.
Reference
Solution structures of the inactive and BeF3-activated response regulator CheY2., Riepl H, Scharf B, Schmitt R, Kalbitzer HR, Maurer T, J Mol Biol. 2004 Apr 23;338(2):287-97. PMID:15066432 Page seeded by OCA on Sun Apr 13 08:09:13 2008