Guanosine-3',5'-bis(diphosphate) 3'-diphosphatase

In enzymology, a guanosine-3',5'-bis(diphosphate) 3'-diphosphatase (EC 3.1.7.2) is an enzyme that catalyzes the chemical reaction

guanosine 3',5'-bis(diphosphate) + H₂O ${\displaystyle \rightleftharpoons }$ guanosine 5'-diphosphate + diphosphate

Thus, the two substrates of this enzyme are and H₂O, whereas its two products are and diphosphate.

This enzyme belongs to the family of hydrolases, specifically those acting on diphosphoric monoester bonds. The systematic name of this enzyme class is guanosine-3',5'-bis(diphosphate) 3'-diphosphohydrolase. Other names in common use include guanosine-3',5'-bis(diphosphate) 3'-pyrophosphatase, PpGpp-3'-pyrophosphohydrolase, and PpGpp phosphohydrolase. This enzyme participates in purine metabolism.

Structural studies[]

As of late 2007, only one structure has been solved for this class of enzymes, with the PDB accession code 1VJ7.

References[]

• Heinemeyer EA, Richter D (1978). "Characterization of the guanosine 5'-triphosphate 3'-diphosphate and guanosine 5'-diphosphate 3'-diphosphate degradation reaction catalyzed by a specific pyrophosphorylase from Escherichia coli". Biochemistry. 17 (25): 5368–72. doi:10.1021/bi00618a007. PMID 365225.
• Richter D, Fehr S, Harder R (1979). "The guanosine 3',5'-bis(diphosphate) (ppGpp) cycle. Comparison of synthesis and degradation of guanosine 3',5'-bis(diphosphate) in various bacterial systems". Eur. J. Biochem. 99 (1): 57–64. doi:10.1111/j.1432-1033.1979.tb13230.x. PMID 114395.