Figure 2.

AMP/product complex of Asp¹⁰ FBPase. Overview of the complex (left). Subunits of the tetramer, labeled C1 through C4, have each one molecule of bound AMP, Fru-6-P (labeled F6P), and P_i and three atoms of Zn²⁺. The side chains of Asp¹⁰ from subunits C1 and C3 are omitted for clarity. Residues 10–25 (helix H1, subunits C1 and C3), 187–195 (loop 190, subunits C1 and C3), 50–72 (dynamic loop, subunits C2 and C4), and 264–274 (subunits C2 and C4) are in bold lines. Rotation of the tetramer by 45° about the horizontal 2-fold axis (right). I_R-state subunits from Leu⁵⁴ FBPase (red lines) are superimposed on the subunits of the I_T-state Asp¹⁰ tetramer (black lines). Shown are only Cα atoms of the I_R subunit that deviate from those of the I_T structure by more than 0.5 Å. This drawing was prepared with MOLSCIRPT.⁶¹