1.7 Å resolution crystal structure of C. immitis RpiB bound to malonic acid. The coloring is the same as used in earlier figures with one protomer in gray and the other in green. Hydrogen bonds are shown as dashed lines. A The |Fo|-|Fc| map calculated with model phases lacking the malonic acid residue is shown in green mesh contoured at 3.0 σ. B The 2|Fo|-|Fc| map calculated with model phases containing the malonic acid residue is shown in blue mesh contoured at 1.0 σ.