Figure 4.

Model of the catalytic core of E9 polymerase. The green ribbons correspond to the homologous region as modeled. Met671 is shown as a red stick model and the active site residues Asp, Thr, Asp, Ser are shown as blue stick models. The yellow ribbons are included to show the remaining part of the catalytic domains of the 1TGO polymerase, but there is no significant amino acid sequence homology between the two polymerases. The figure was prepared with PyMol.