Figure 5.

Superposition of common structural elements. (A) Stereo image depicting the superposition of the 12 reference structures only around the common structural elements, β-sheet strands βI (turquoise), βII (brown), βIII (orange), βIV (yellow), and βV (blue), as well as backing helices αA (pink), active-site helices αB (white), and C-terminal helices αC (red). (B) Superposition of the active-site helix and the downstream chain segment until the family-specific residue plus the Met-turn of AST (white), ADA (gold), SER (pink), LEI (purple), MMP (turquoise), and SNA (green) in two orthogonal views. The catalytic metal ions have been omitted for clarity. (C) Same as (B) but showing AMZ (blue), FRA (red), IGA (orange), CHO (tan), PAP (salmon), and TOX (sienna).