As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes 1GPM, 1WL8, 2A9V, 2D7J, and 2DPL.

[7] GMP synthase is also involved in amino acid metabolism because it generates L-glutamate from L-glutamine.

[7] This enzyme is widely distributed and a number of crystal structures have been solved, including in Escherichia coli, Pyrococcus Horikoshii, Thermoplasma acidophil, Homo sapiens, Thermus thermophilus and Mycobacterium tuberculosis.

[1] This enzyme also binds several ligands, including phosphate, pyrophosphate, AMP, citrate and Magnesium.

It falls into a nucleophile elbow, where it is at the end of a beta strand and the beginning of an alpha helix, and has little flexibility in its phi and psi angles; thus, Gly84 and Gly88 are conserved and allow for the tight packing of amino acids surrounding the catalytic residue.

The ATP Pyrophosphatase domain consists of a beta sheet containing 5 parallel strands with several alpha helices on each side.