In enzymology, a glucose-1-phosphate adenylyltransferase (EC 2.7.7.27) is an enzyme that catalyzes the chemical reaction
| glucose-1-phosphate adenylyltransferase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 Glucose-1-phosphate adenylyltransferase tetramer, Rhizobium radiobacter | |||||||||
| Identifiers | |||||||||
| EC no. | 2.7.7.27 | ||||||||
| CAS no. | 9027-71-8 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
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- ATP + alpha-D-glucose 1-phosphate diphosphate + ADP-glucose
Thus, the two substrates of this enzyme are ATP and alpha-D-glucose 1-phosphate, whereas its two products are diphosphate and ADP-glucose.
This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is ATP:alpha-D-glucose-1-phosphate adenylyltransferase. Other names in common use include ADP glucose pyrophosphorylase, glucose 1-phosphate adenylyltransferase, adenosine diphosphate glucose pyrophosphorylase, adenosine diphosphoglucose pyrophosphorylase, ADP-glucose pyrophosphorylase, ADP-glucose synthase, ADP-glucose synthetase, ADPG pyrophosphorylase, ADP:alpha-D-glucose-1-phosphate adenylyltransferase and AGPase.
This enzyme participates in starch and sucrose metabolism and glycogen metabolism in bacteria. The rate limiting step in their synthesis appears to be regulated at the level of this enzyme. In many species glycolytic intermediates act to stimulate enzyme activity while AMP or phosphate inhibit enzyme activity.
In contrast, in many animals, the synthesis of alpha 1,4 glucans (glycogen) uses UDP-glucose as a glucose donor. In this case, the regulated step is instead the glycosyl transferase.
Structural studies
editAs of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 1YP2, 1YP3, and 1YP4.
References
edit- Ghosh HP, Preiss J (1966). "Adenosine diphosphate glucose pyrophosphorylase. A regulatory enzyme in the biosynthesis of starch in spinach leaf chloroplasts". J. Biol. Chem. 241 (19): 4491–504. doi:10.1016/S0021-9258(18)99747-4. PMID 5922972.
- Shen L; Preiss J (1965). "Biosynthesis of bacterial glycogen. I. Purification and properties of the adenosine diphosphoglucose pyrophosphorylase of Arthrobacter species NRRL B1973". J. Biol. Chem. 240 (6): 2334–2340. doi:10.1016/S0021-9258(18)97327-8. PMID 14304834.
