Stereo view of superimposition of the Pi binding site of BbXFPK with ScTK (A) and LpPOX (B). A, shown is superimposition of the AcThDP and Pi complex structures of BbXFPK (yellow for protein and green for cofactor) and the resting structure of ScTK (PDB code 1TRK, gray). Labels in parentheses are those of ScTK. B, shown is superimposition of the AcThDP intermediate and Pi complex structures of BbXFPK (C and P atoms are in green and orange, respectively), and Pi complexed with α-hydroxyethyl-ThDP adduct of LpLOX (2EZT, C and P atoms are in gray).