Publication Abstract from PubMed
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.
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[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
