Structural alignment of cyclopropane fatty acid synthase and Rossmann-fold methyltransferase. Red color – YecO methyltransferase (PDB structure 1IM8:A) Yellow color – ligand in YecO methyltransferase. Green color – mycolic acid cyclopropane synthase CmaA2 (PDB structure 1KPI:A). Blue color – three ligands in CmaA2 (PDB structure 1KPI:A). Motifs I-VI conserved in Rossmann-fold methyltransferases are labeled above the alignment.