View source for 2osv

[[Image:2osv.gif|left|200px]]<br /><applet load="2osv" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="2osv, resolution 1.750&Aring;" />
'''Crystal Structure of ZnuA from E. coli'''<br />

==Overview==
Bacterial ATP-binding cassette transport systems for high-affinity uptake, of zinc and manganese use a cluster 9 solute-binding protein. Structures, of four cluster 9 transport proteins have been determined previously., However, the structural determinants for discrimination between zinc and, manganese remain under discussion. To further investigate the variability, of metal binding sites in bacterial transporters, we have determined the, structure of the zinc-bound transport protein ZnuA from Escherichia coli, to 1.75 A resolution. The overall structure of ZnuA is similar to other, solute-binding transporters. A scaffolding alpha-helix forms the backbone, for two structurally related globular domains. The metal-binding site is, located at the domain interface. The bound zinc ion is coordinated by, three histidine residues (His78, His161 and His225) and one glutamate, residue (Glu77). The functional role of Glu77 for metal binding is, unexpected, because this residue is not conserved in previously determined, structures of zinc and manganese-specific transport proteins. The observed, metal coordination by four protein residues differs significantly from the, zinc-binding site in the ZnuA transporter from Synechocystis 6803, which, binds zinc via three histidine residues. In addition, the E. coli ZnuA, structure reveals the presence of a disulfide bond in the C-terminal, globular domain that is not present in previously determined cluster 9, transport protein structures.

==About this Structure==
2OSV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2OSV OCA]. 

==Reference==
Crystal Structure of the Zinc-binding Transport Protein ZnuA from Escherichia coli Reveals an Unexpected Variation in Metal Coordination., Li H, Jogl G, J Mol Biol. 2007 Mar 15;. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17399739 17399739]
[[Category: Escherichia coli]]
[[Category: Single protein]]
[[Category: Jogl, G.]]
[[Category: Li, H.]]
[[Category: ZN]]
[[Category: protein-zinc complex]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 13:17:20 2007''