2jsc
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NMR structure of the cadmium metal-sensor CMTR from Mycobacterium tuberculosis
OverviewOverview
CmtR from Mycobacterium tuberculosis is a winged helical DNA-binding, repressor of the ArsR-SmtB metal-sensing family that senses cadmium and, lead. Cadmium-CmtR is a dimer with the metal bound to Cys102 from the, carboxyl-terminal region of one subunit and two Cys associated with helix, alphaR from the other sub-unit, forming a symmetrical pair of, cadmium-binding sites. This is a significant novelty in the ArsR-SmtB, family. The structure of the dimer could be solved at 312K. The apo, protein at the same temperature is still a dimer but it experiences a, large conformational exchange at the dimer interface and within each, monomer. This is monitored by an overall decrease of the number of NOEs, and by an increase of H2O-D2O exchange rates, especially at the dimeric, interface, in the apo form with respect to the Cd-bound state. The, C-terminal tail region is completely unstructured in both apo and cadmium, forms but becomes less mobile in the cadmium-bound protein due to the, recruitment of Cys102 as a metal-ligand. DNA binds to the apo dimer with a, ratio 1:3 at mM concentration. Addition of cadmium to the apo-CmtR DNA, complex causes DNA detachment, restoring the NMR spectrum of free, cadmium-CmtR. Cadmium-binding across the dimer interface impairs, DNA-association by excluding the apo-conformers suited to bind DNA.
About this StructureAbout this Structure
2JSC is a Single protein structure of sequence from Mycobacterium tuberculosis with as ligand. Full crystallographic information is available from OCA.
ReferenceReference
NMR structural analysis of cadmium-sensing by winged helix repressor CMTR., Banci L, Bertini I, Cantini F, Ciofi-Baffoni S, Cavet JS, Dennison C, Graham A, Harvie DR, Robinson NJ, J Biol Chem. 2007 Jun 27;. PMID:17599915
Page seeded by OCA on Wed Jan 23 12:32:15 2008
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OCA- Pages with broken file links
- Mycobacterium tuberculosis
- Single protein
- Banci, L.
- Bertini, I.
- Cantini, F.
- Cavet, J.S.
- Ciofi-Baffoni, S.
- Dennison, C.
- Graham, A.I.
- Harvie, D.R.
- Robinson, N.J.
- SPINE, Structural.Proteomics.in.Europe.
- CD
- Cadmium
- Nmr
- Solution structure
- Spine
- Structural genomics
- Structural proteomics in europe
- Transcriptional repressor