The overall structure of the CmoA dimer. (a) Two orthogonal views of the two monomers forming the dimer (green and blue ribbons). The S-adenosyl-S-carboxymethyl-L-homocysteine (SCM-SAH) cofactor is shown with O atoms in red, N atoms in blue and C atoms in green. (b) The SEC-SLS chromatogram that confirms that CmoA is a dimer in solution. The refractive index (RI; red line) and right-angle light scattering (RALS; green line) traces are displayed. The molecular weight calculated by the OmniSEC software (MW; black line) is shown above the elution peak. The dispersity, Mw/Mn, defined as the ratio of the weight average to number average molecular weights was reported to be 1.001, indicating a highly uniform sample.