Figure 1.

The homotetrameric (top) and subunit (bottom) structures of rM₁-PYK as determined by x-ray crystallography (PDB: 2G50). Subunits within the homotetramer are colored red, light blue, green, and gray. Each subunit contains three domains labeled as A, B, and C. The active site lies between the A and B domains, whereas the amino acid allosteric site is located at the A-C domain interface. The presentation of the subunit (bottom) distinguishes the three domains with various shades of gray. In both homotetrameric and subunit views, the active site is occupied by spacefill views of potassium (blue), Mn²⁺ (cyan), and pyruvate (red). The allosteric amino-acid binding site is occupied by Ala (green spacefill). This figure and legend are reproduced from (27). To see this figure in color, go online.