Figure 6. Comparison of CMTr1_126–550 with the viral VP39 enzyme.

(a) Superimposition of CMTr1_126–550 substrate complex (orange) on VP39 (PDB ID: 1AV6). (grey) in complex with capped oligoribonucleotide (blue) and SAH (purple). The structures were superimposed using the C-α atoms from the central β-sheet. (b) Close-up view of the m⁷G-binding pocket. For CMTr1_126–550, the protein is coloured orange, and m⁷G is coloured yellow. For VP39, the protein is coloured grey, and m⁷G is coloured blue. (c,d) Close-up views of the interactions in m⁷G binding in VP39 MTase (c) and CMTr1_126–550 (d).