FIGURE 7.

Structural comparison of the substrate-binding clefts of Chi23, ChiNCTU2, MmChi60 and SmChiC. (A) The substrate-binding clefts of Chi23, ChiNCTU2 (PDB code 3N18), MmChi60 (PDB code 4MB5) and SmChiC (PDB code 4AXN). The substrate-binding clefts are shown as surface and colored in apricot. The (GlcNAc)₅ docked into Chi23, the (GlcNAc)₄ bound to ChiNCTU2, and the (GlcNAc)₅ bound to MmChi60 are shown as yellow sticks. (B–E) Superposition of the substrate-binding clefts of Chi23 (magenta) and ChiNCTU2 (cyan) or/and MmChi60 (yellow) or/and SmChiC (gray). In (B–E), the (GlcNAc)₅ docked into Chi23 is shown as green lines. Residues involved in the catalysis and substrate binding are shown as sticks, and colored in magenta for Chi23, in cyan for ChiNCTU2, in yellow for MmChi60, and in gray for SmChiC.