Fig. 5

SAXS analysis of nucleotide binding to the HK domain. Real-space distance distributions p(r) of the HK domain with no ligand (gray) and in the presence of 10 µM of APPCP (blue), or 10 µM of ATP (green). b Dimensionless Kratky plot of the data in a, highlighting the change toward a more compact and less-flexible structure when either APPCP or ATP are added to the HK domain. c SAXS data for the ligand-free HK domain, fitted with the homology model depicted in d. e SAXS data for the Mg-APPCP-bound HK domain, fitted with the homology model (red), as well as with the best SAXS-refined elastic network conformation (black). f Conformational transitions from the template homology model refined against the Mg-APPCP-bound data in e. Vectors describe the direction of motion. g SAXS data and corresponding fits as in e for the Mg-ATP bound HK domain. h The derived conformational transitions from g are virtually identical to the ones obtained for Mg-APPCP in f. No effect was noted upon addition of the protein kinase C inhibitor Ro 31-8220