https://www.ncbi.nlm.nih.gov/Structure/pdb/1CG4
1CG4: STRUCTURE OF THE MUTANT (R303L) OF ADENYLOSUCCINATE SYNTHETASE FROM E. COLI COMPLEXED WITH,...
PROTEIN (ADENYLOSUCCINATE SYNTHETASE)6-O-PHOSPHORYL INOSINE MONOPHOSPHATEGUANOSINE-5'-DIPHOSPHATEMAGNESIUM ION