... from low amounts of pantoate [9]. Here, wereport the results of the structural studies of the panto-ate-bound form of the N-terminal domain of E. coliPS (nPS). The structure and substrate- binding ... molecule takes the position of the adenine ring of ATP. The carbon and oxygen atoms of pantoate are shown inyellow and red, respectively. The carbon and oxygen atoms of ATP are shown in red, the nitrogen ... the substrates of a reaction has also been observed in the case of ade-nylosuccinate synthetase, one of whose substrates,IMP, binds to the GTP-binding site and inhibits the reaction [37–39]. The...