|PROSITE documentation PDOC51553 [for PROSITE entry PS51553]|
Guanosine 5'-monophosphate synthetase (GMPS) is a widespread enzyme seen in all domains of life. GMPS is required for the final step of the de novo synthesis of guanine nucleotides, converting xanthosine 5'-monophosphate (XMP) into guanosine 5'-monophosphate (GMP), a precursor of DNA and RNA. GMPS consists of two catalytic units, glutamine amidotransferase (GATase) (see <PDOC00405>) and ATP pyrophosphatase (ATP-PPase). GATase hydrolyzes glutamine to yield glutamate and ammonia, while ATP-PPase utilizes ammonia to convert adenyl xanthosine 5'-monophosphate (adenyl-XMP) into GMP. The two catalytic units are either encoded by a single gene (two-domain type) in eucaryotes, bacteria, and some archaea, or encoded by two separate genes (two-subunit type) in other archaea. In two-domain-type GMPS, the GATase domain is located in the N-terminal half, and the ATP-PPase domain is located in the C-terminal half; in two-subunit-type GMPS, these two units exist as separate polypeptides. ATP-PPase consists of two domains (N-domain and C-domain). The N-domain contains an ATP-binding platform called P-loop (see <PDOC00017>), whereas the C-domain contains the XMP-binding site and also contributes to homodimerization [1,2,3].
The GMP synthetase ATP-PPase ATP-binding domain is a twisted, five-stranded parallel β-sheet sandwiched between helical layers (see <PDB:1GPM>). It contains a glycine rich ATP-binding motif called the "P-loop motif" located after the first β-strand [1,3].
The profile we developed covers the entire GMPS ATP-PPase domain.Last update:
November 2011 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Tesmer J.J.G. Klem T.J. Deras M.L. Davisson V.J. Smith J.L.|
|Title||The crystal structure of GMP synthetase reveals a novel catalytic triad and is a structural paradigm for two enzyme families.|
|Source||Nat. Struct. Biol. 3:74-86(1996).|
|2||Authors||Grimaldi C. Dutertre M. Simonet J.-M.|
|Title||Genetic organization and polymorphism of the guaA gene encoding the GMP synthetase in Lactobacillus rhamnosus.|
|Source||Curr. Microbiol. 40:245-249(2000).|
|3||Authors||Maruoka S. Horita S. Lee W.C. Nagata K. Tanokura M.|
|Title||Crystal structure of the ATPPase subunit and its substrate-dependent association with the GATase subunit: a novel regulatory mechanism for a two-subunit-type GMP synthetase from Pyrococcus horikoshii OT3.|
|Source||J. Mol. Biol. 395:417-429(2010).|