Guanosine-triphosphate guanylyltransferase explained

guanosine-triphosphate guanylyltransferase
Ec Number:	2.7.7.45
Cas Number:	54576-89-5
Go Code:	0047351

In enzymology, a guanosine-triphosphate guanylyltransferase is an enzyme that catalyzes the chemical reaction

2 GTP

\rightleftharpoons diphosphate + P₁,P₄-bis(5'-guanosyl) tetraphosphate

Hence, this enzyme has one substrate, GTP, and two products, diphosphate and P1,P4-bis(5'-guanosyl) tetraphosphate.

This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is GTP:GTP guanylyltransferase. Other names in common use include diguanosine tetraphosphate synthetase, GTP-GTP guanylyltransferase, Gp4G synthetase, and guanosine triphosphate-guanose triphosphate guanylyltransferase.

References

• Warner AH, Beers PC, Huang FL . 1974 . Biosynthesis of the diguanosine nucleotides. I. Purification and properties of an enzyme from yolk platelets of brine shrimp embryos . Can. J. Biochem. . 52 . 231 - 40 . 4208243 . 3 . 10.1139/o74-036.