Pegos Vanessa R, Hey Louis, LaMirande Jacob, Pfeffer Rachel, Lipsh Rosalie, Amitay Moshe, Gonzalez Daniel, Elias Mikael
Biochemistry, Molecular Biology and Biophysics Department and BioTechnology Institute, University of Minnesota, Saint Paul, MN 55108, USA.
Department of Bioinformatics, The Jerusalem College of Technology - Lev Academic Center, Jerusalem 91160, Israel.
Acta Crystallogr F Struct Biol Commun. 2017 Jun 1;73(Pt 6):342-346. doi: 10.1107/S2053230X17007373. Epub 2017 May 25.
Phosphate-binding proteins (PBPs) are key proteins that belong to the bacterial ABC-type phosphate transporters. PBPs are periplasmic (or membrane-anchored) proteins that capture phosphate anions from the environment and release them to the transmembrane transporter. Recent work has suggested that PBPs have evolved for high affinity as well as high selectivity. In particular, a short, unique hydrogen bond between the phosphate anion and an aspartate residue has been shown to be critical for selectivity, yet is not strictly conserved in PBPs. Here, the PBP from Polaromonas JS666 is focused on. Interestingly, this PBP is predicted to harbor different phosphate-binding residues to currently known PBPs. Here, it is shown that the PBP from Polaromonas JS666 is capable of binding phosphate, with a maximal binding activity at pH 8. Its structure is expected to reveal its binding-cleft configuration as well as its phosphate-binding mode. Here, the expression, purification, characterization, crystallization and X-ray diffraction data collection to 1.35 Å resolution of the PBP from Polaromonas JS666 are reported.
磷酸盐结合蛋白（PBPs）是属于细菌ABC型磷酸盐转运蛋白的关键蛋白。PBPs是周质（或膜锚定）蛋白，可从环境中捕获磷酸根阴离子并将其释放到跨膜转运蛋白中。最近的研究表明，PBPs已经进化出高亲和力和高选择性。特别是，磷酸根阴离子与天冬氨酸残基之间的一个短而独特的氢键已被证明对选择性至关重要，但在PBPs中并不严格保守。在此，重点研究了极地单胞菌JS666的PBP。有趣的是，预测这种PBP具有与目前已知的PBPs不同的磷酸盐结合残基。在此表明，极地单胞菌JS666的PBP能够结合磷酸盐，在pH 8时具有最大结合活性。预计其结构将揭示其结合裂隙构型及其磷酸盐结合模式。在此报告了极地单胞菌JS666的PBP的表达、纯化、表征、结晶以及分辨率达到1.35 Å的X射线衍射数据收集情况。
