Fig. 3
Three-dimensional mapping of the Arg309His substitution in the ADSL holoenzyme. On the left side of the panel, localization of Arg309 in the ADSL protein homotetramer (the four subunits are in different colors) complexed with adenylosuccinic acid (S-AMP) substrate, and its enzymatic products adenosine monophosphate (AMP) and fumaric acid (FA) (PDB accession number 2VD6). On the right side of the panel, the inset shows a slab view of Arg309 in one ADSL subunit forming a salt-bridge with Asp332 of the neighboring subunit, and the nearby Leu331 and Ser334 that bind to the substrate (interactions are represented by dots between atoms)