Fig. 3: Binding of 5-InsP7, 6-InsP7 and 5-PCF2Am-InsP5 by AtPFA-DSP149–215.
a Surface representation colored to match structural elements correspond to gray for P-loop, cyan for α5-α6 loop, purple for WPD-loop, and yellow for the remainder. The 5-InsP7 is shown in stick format; carbon is white, phosphorus is orange and oxygen is red. Phosphate groups are numbered according to standard nomenclature. Panel (b) shows a similar orientation of 5-InsP7, with key interacting residues in stick format; nitrogen is blue, and oxygen. Panel (c) is a rendering of the ligand–protein interactions created by Ligplot+. Polar contacts within 3.2 Å are depicted with broken green lines. Hydrophobic interactions are shown in grey eyelash style. Equivalent data are shown in panels (d, e) for 6-InsP7 as the ligand; the latter’s carbons are colored dark gray. Panel (f) superimposes 6-InsP7 (dark gray; numbers denote positions of 2- and 6-phosphates) upon 5-InsP7 (light gray; boxed numbers denote 2- and 5-phosphates). Panels (g, h) compare the chemical structures of the α-phosphono-α,α-difluoroacetamide group (PCF2Am; blue) and the 5-diphosphate group (PP; red)respectively. Panels (i, j), show binding interactions for 5-PCF2Am-InsP5 (carbon is pink, and fluorine is cyan). Panel (k) superimposes 5-PCF2Am-InsP5 upon 5-InsP7 using the same color schemes as in panels (i, f) The omit Fo-Fc electron density maps, contoured at 5σ, are shown in green mesh. Source data files are provided as PDB accession codes 7MOE, 7MOF and 7MOG.
