2asr
From Proteopedia
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THE THREE-DIMENSIONAL STRUCTURE OF THE ASPARTATE RECEPTOR FROM ESCHERICHIA COLI
Overview
The crystal structure of the periplasmic domain of the aspartate receptor, from Escherichia coli has been solved and refined to an R-factor of 0.203, at 2.3 A, resolution. The dimeric protein is largely helical, with four, helices from each monomer forming a four-helix bundle. The dimer interface, is constructed from four helices, two from each subunit, also packed, together in a four-helix bundle arrangement. A sulfate ion occupies the, aspartate-binding site. All hydrogen bonds made to aspartate are, substituted by direct or water-mediated hydrogen bonds to the sulfate., Comparison of the Escherichia coli aspartate-receptor structure with that, of Salmonella typhimurium [Milburn, Prive, Milligan, Scott, Yeh, Jancarik, Koshland & Kim (1991). Science, 254, 1342-1347; Scott, Milligan, Milburn, Prive, Yeh, Koshland & Kim (1993). J. Mol. Biol. 232, 555-573] reveals, strong conservation in the structure of the monomer, but more divergence, in the orientation of the subunits with respect to one another. Mutations, that render the Escherichia coli receptor incapable of responding to, maltose are either located in spatially conserved sites or in regions of, the structures that have high temperature factors and are therefore likely, to be quite flexible. The inability of the receptor from Salmonella, typhimurium to respond to maltose may, therefore, be because of, differences in amino acids located on the binding surface rather than, structural differences.
About this Structure
2ASR is a Single protein structure of sequence from Escherichia coli with SO4 as ligand. Full crystallographic information is available from OCA.
Reference
The three-dimensional structure of the aspartate receptor from Escherichia coli., Bowie JU, Pakula AA, Simon MI, Acta Crystallogr D Biol Crystallogr. 1995 Mar 1;51(Pt 2):145-54. PMID:15299315
Page seeded by OCA on Wed Nov 21 08:20:47 2007
