1pbp
FINE TUNING OF THE SPECIFICITY OF THE PERIPLASMIC PHOSPHATE TRANSPORT RECEPTOR: SITE-DIRECTED MUTAGENESIS, LIGAND BINDING, AND CRYSTALLOGRAPHIC STUDIES
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OverviewOverview
Phosphorous, primarily in the form of phosphate, is a critical nutrient, for the life of a cell. We have previously determined the 1.7-A resolution, structure of the phosphate-binding protein, an initial receptor for the, high-affinity phosphate active transport system or permease in Escherichia, coli (Luecke, H., and Quiocho, F.A. (1990) Nature 347, 402-406). This, structure is the first to reveal the key role of hydrogen bonding, interactions in conferring the high specificity of the permease, a, specificity also shared by other phosphate transport systems. Both, monobasic and dibasic phosphates are recognized by the phosphate-binding, protein with Asp56 playing a key role. Here we report site-directed, mutagenesis, ligand binding, and crystallographic studies of the binding, protein which show that introduction of one additional Asp by mutagenesis, of the Thr141 in the ligand-binding site restricts binding to only the, monobasic phosphate.
About this StructureAbout this Structure
1PBP is a Single protein structure of sequence from Escherichia coli with PO4 as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Fine tuning the specificity of the periplasmic phosphate transport receptor. Site-directed mutagenesis, ligand binding, and crystallographic studies., Wang Z, Choudhary A, Ledvina PS, Quiocho FA, J Biol Chem. 1994 Oct 7;269(40):25091-4. PMID:7929197
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