GMP synthase (glutamine—hydrolysing)

The GMP synthase is the enzyme in all living things, which catalyzes the last step in the de novo synthesis of GMP: the conversion of Xanthosinmonophosphat (XMP ). GMP is the precursor both of the nucleotide GTP, ATP, the similar functions as an energy carrier, as well as the purine base, guanosine, which is indispensable in the genome.

The reaction takes place in two steps by cleavage of the Polyphosphatrests ATP followed by the hydrolysis of glutamine to transfer of the amino group. The two individual reactions are catalyzed by a respective own domain, both of which are located on the enzyme. Only some archaea have a single enzyme for each domain.

Catalyzed reaction


From XMP, ATP, and glutamine arises GMP, AMP, and glutamic acid.