Electrostatic potential of the protein surface mapped on the ecMnmC structure. Positive or negative electrostatic isosurface was plotted at contour levels of + kT/e (blue), or – kT/e (red), respectively. A) FAD binding pocket, with FAD represented as green sticks, B) SAM binding pocket with SAM in green stick. C) The protein is oriented with no active site visible. Note that this surface is mostly electronegative in contrast to A) and B).