Figure 12.
Active-site region of [NiFe] hydrogenases contain ordered crystallographic water molecules, demonstrated here for E. coli Hyd-1.54 The water molecules denoted in red spheres were found to be highly conserved in a range of Hyd-1 variants, whereas an additional water (blue sphere) was present in the R509K variant reported by Armstrong and co-workers. A stereo view of this figure is presented in the Supporting Information, Figure S2. Adapted with permission from ref (54). Copyright 2015 Nature Publishing Group.