Fig. S3.
Alternative conformations of the Glu66 side chains. Snapshots of the relative orientations and hydrogen-bonding patterns of Glu66 observed in the structures described herein. The neighboring molecule is shown in dark green; side-chain residues involved in the interactions are shown. For alkali cations (I4 space group), A and B indicates A and B molecule, respectively. For organic compounds (P2221 space group), A, B, C, and D indicate the four different chains that form two independent tetramers (AABB and CCDD).