Figure 10.

a) The 90 K x-ray crystal structure of BtuB W371R (PDB ID: 3RGN) determined at 2.3 Å showing the R1 side chain (in a stick representation) and the positions of the nearest neighbor residues in a Corey, Pauling Koltun rendering. In b) and c) are shown alternate views of the site around W371R1, with the van der Waals surface shown in grey. W371R1 sits in a pocket formed by residues T373 and Y389. In b) the 2F_o-F_c electron density is shown as blue mesh contoured at 1σ. Data collection and refinement statistics are given in Table 1.