Figure 4.
Superposition of OccJ and LAO binding site showing octopine in pink/magenta in OccJ and arginine in pink in LAO (PDB code 1LAF). (a) Ser72 and Asp161 in LAO (Ser91 and Asn202 in OccJ) bind the NH3 + group of the arginine ligand. Asp161 side chain position is not compatible with a bound octopine in LAO. Double arrows indicate distances. (b) Asp161 side chain in LAO is hydrogen bonded with Gln122, which in turn interacts with Ser92.