Binding pose of two cytidine nucleotides in Bc IspF. Hydrogen bonding interactions between Bc IspF, water molecules and both CMP molecules in one active site are depicted with black dashed lines. Residues that contribute to binding interactions only via the main chain are depicted without side chain atoms. Solvent molecules are depicted as red spheres. Components of one subunit are shown with C atoms yellow and for the other subunit, cyan. Electron density is displayed for CMP 2 as green chicken-wire corresponding to an |Fo-Fc| map (omit map) contoured at 2.5 σ.