Figure 1 - full size

 

Figure 1.
Figure 1 Structure of the primer protein VPg in a complex with 3D. (A) Stereo view of a sigma A weighted |F[o]|-|F[c]| electron density map at 2.9 Å resolution and contoured at 3.0 around the VPg-UMP molecule (The VPg-UMP and ions were omitted from the phasing model). The 15 amino acids of VPg, the UMP covalently linked to the protein and the metal ions are placed inside the density in ball and stick representation colored in atom type code. Names for all residues are explicitly labeled in one letter code. (B) Details of the interactions seen in the active site of the 3D polymerase during the uridylylation reaction. The residues Pro2, Tyr3 and Ala4 of VPg are shown in sticks in red and the UMP, covalently linked to the hydroxyl group of Tyr3, in light green. The divalent cations Mn2+ and Mg2+ are shown as magenta and orange spheres, respectively, and the anomalous difference Fourier map is shown as a chicken wire in blue. The 3D amino acids involved in direct hydrogen bonds with ions and the uridylylated tyrosine are shown in ball and sticks in atom type code, and the hydrogen bonds appear as dashed lines. All residues are explicitly labeled. The predicted position of the oligo(A) template strand (dark green) was determined using the 3D-RNA template-primer complex (PDB entry 1WNE) as a guide.

The above figure is reprinted by permission from Macmillan Publishers Ltd: EMBO J (2006, 25, 880-888) copyright 2006.