Figure 3

The binding mode of the two citrate molecules. (A) Electron density of the two citrate molecules FLC1 and FLC2 (2Fo-Fc map contoured at 1.2 σ). (B) A closer look of the conserved residues binding to the two citrate molecules. The C terminal tail of chain B is colored in grey, and chain A in cyan. (C) Superimposed structures of Gnd1 (in cyan) with sheep liver 6PGDH (PDB code: 1PGP; colored in grey). The two citrate molecules (shown in sticks) are superimposed on one molecule of 6PG (shown in sticks) of 1PGP. (D) The surface comparison between yeast Gnd1 bound to two citrate molecules (a, a' and a") and sheep liver 6PGDH monomer bound to 6PG (b, b' and b"). The monomer omitting the bound ligand, the ligand and the complex are shown in a/b, a'/b' and a"/b", respectively.