Figure 2.

(A) A ribbons diagram of the AMCase catalytic domain is color-ramped blue to red, looking down the central β-barrel. Methylallosamidin is show in pale cyan, bound at the top of the barrel. A disulfide bond between Cys-49 and Cys-394 can be seen near the back, connecting the C-terminal end (in red) to an N-terminal loop (in blue). (B) A surface rendition in the same orientation as 2A shows the aromatic residues implicated in chitin binding in red. Methylallosamidin is shown in pale cyan, the subunits of which correspond to subsite positions −1, −2, and −3, from left to right. Positive subsite positions extend towards the left in this view, with subsite +1 just under Trp-99 and subsite +2 just above Trp-218.