view article

Figure 2
Mg2+ coordination around the active site of E. coli RNase HI. (a) Overall structure of E. coli RNase HI in complex with Mg2+. (b) The 2FoFc electron-density map (1.3σ) of active-site residues and ligands involved in Mg2+–RNase HI coordination is shown as a gray mesh. Distances (in Å) between the Mg2+ ions and their coordinating ligands are indicated, as well as that for Mg2+ A–Mg2+ B. H2Oδ is kept in the active site both by hydrogen bonds to Asp70 and the coordination by Mg2+ B (shown as light blue dotted lines). The Mg2+ ions are colored green, H2Oδ red and the other surrounding waters light pink. (c) Superposition of the singly Mg2+-bound E. coli RNase HI (PDB entry 1rdd, cyan) and RNH_Mg_3 (orange). Mg2+ ions and water molecules are shown as large and small spheres in the same color as the protein. Putative coordination in RNH_Mg_3 is shown as purple dashed lines.

Journal logoSTRUCTURAL
BIOLOGY
ISSN: 2059-7983
Follow Acta Cryst. D
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds