In enzymology, a phosphoribosylamine-glycine ligase (EC 184.108.40.206) is an enzyme that catalyzes the chemical reaction
- ATP + 5-phospho-D-ribosylamine + glycine ADP + phosphate + N1-(5-phospho-D-ribosyl)glycinamide
The 3 substrates of this enzyme are ATP, 5-phospho-D-ribosylamine, and glycine, whereas its 3 products are ADP, phosphate, and N1-(5-phospho-D-ribosyl)glycinamide.
This enzyme belongs to the family of ligases, specifically those forming generic carbon-nitrogen bonds. This enzyme participates in purine metabolism.
Bacterial genes that encode this enzyme are often named purD. The purD genes often contain PurD RNA motif in their 5' UTR.
In bacteria, GARS is a monofunctional enzyme (encoded by the purD gene). In yeast, GARS is part of a bifunctional enzyme (encoded by the ADE5/7 gene) in conjunction with phosphoribosylformylglycinamidine cyclo-ligase (AIRS). In higher eukaryotes, GARS is part of a trifunctional enzyme in conjunction with AIRS and with phosphoribosylglycinamide formyltransferase (GART), forming GARS-AIRS-GART.
The systematic name of this enzyme class is 5-phospho-D-ribosylamine:glycine ligase (ADP-forming). Other names in common use include:
- phosphoribosylglycinamide synthetase,
- glycinamide ribonucleotide synthetase,
- phosphoribosylglycineamide synthetase,
- glycineamide ribonucleotide synthetase,
- 2-amino-N-ribosylacetamide 5'-phosphate kinosynthase,
- 5'-phosphoribosylglycinamide synthetase, and
- GAR synthetase.
As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 1GSO, 1VKZ, and 2QK4.
- GOLDTHWAIT DA, GREENBERG GR, PEABODY RA (1956). "On the mechanism of synthesis of glycinamide ribotide and its formyl derivative". J. Biol. Chem. 221 (2): 569–77. PMID 13357451.
- HARTMAN SC, BUCHANAN JM (1958). "Biosynthesis of the purines. XXII 2-Amino-N-ribosylacetamide-5'-phosphate kinosynthase". J. Biol. Chem. 233 (2): 456–61. PMID 13563520.
This article incorporates text from the public domain Pfam and InterPro IPR020560
This article incorporates text from the public domain Pfam and InterPro IPR020562
This article incorporates text from the public domain Pfam and InterPro IPR020561