GMP synthetase ATP pyrophosphatase domain (IPR025777)

Short name: GMPS_ATP_PPase_dom

Overlapping homologous superfamilies

Domain relationships

  • NAD/GMP synthase (IPR022310)
    • GMP synthetase ATP pyrophosphatase domain (IPR025777)


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) and ATP pyrophosphatase (ATP-PPase). GATase hydrolyzes glutamine to yield glutamate and ammonia, while ATP-PPase utilises 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, whereas the C-domain contains the XMP-binding site and also contributes to homodimerisation [PMID: 8548458, PMID: 10688693, PMID: 19900465].

The GMP synthetase ATP-PPase ATP-binding domain is a twisted, five-stranded parallel beta-sheet sandwiched between helical layers. It contains a glycine rich ATP-binding motif called the "P-loop motif" located after the first beta-strand [PMID: 8548458, PMID: 19900465].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005524 ATP binding
GO:0016462 pyrophosphatase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles