Figure 6.
Substrate dependent conformational switch. (a) The new structure of TDG82-308 (cyan) bound to cadCF DNA (yellow) superimposed with the previous structure of TDG82-308 bound to fdCF DNA (pink) (PDB ID 5T2W). Red (or pink) spheres represent water molecules. For cadC DNA, the water molecule of interest receives a hydrogen bond from a backbone nitrogen (G154), while for fdC DNA, the corresponding water (pink) donates a hydrogen bond to a backbone oxygen (P153). Cis-trans isomerization is shown for P155 (b) Effect of the conformational switch on hydrogen bond interactions of the ordered water molecule and its capacity to provide a hydrogen bond to the carboxylate of caC.