Figure 3

The ligand-binding pocket of TdcF in the empty, ethylene glycol-bound and serine-bound states. Stereoviews showing 2mF _obs - dF _calc electron density maps contoured at approximately 1 sigma superposed on TdcF binding pockets in the following states: (A) empty (1.6 Å resolution); (B) with ethylene glycol bound (2.35 Å resolution); (C) with serine bound (1.6 Å resolution), where #1 and #2 denote alternate conformers for the Oγ. Important hydrogen bonds are shown as dashed lines. Residues from different subunits are labelled green and blue, respectively. In all cases, the side-chain of Arg-105 makes a bi-dentate interaction with the Oδ1 of Asn-88, which is just visible in the left foreground; and Oε1 of Glu-120 makes an inter-subunit hydrogen bond with the carbonyl oxygen of Cys-107. Throughout this figure, the view is similar to that seen in the inset of Figure 2. Figure generated using PyMOL [31].