Figure 2. Crystal structure of BthII1283.

(A) Ribbon representation of BthII1283. The Class I methyltransferase fold, N-terminal extension, first internal extension, and second internal extension are colored light blue, salmon, light green, and light purple, respectively. SAH and 1,6-DDMTare shown as balls and sticks. (B) Structural topology diagram. Helices and β-strands are shown as cylinders and large arrows, respectively. (C) Crystallography asymmetric unit. Monomer A is on the left and monomer B is on the right.