Galactinol—raffinose galactosyltransferase explained

galactinol-raffinose galactosyltransferase
Ec Number:	2.4.1.67
Cas Number:	37277-70-6
Go Code:	0047268

In enzymology, a galactinol-raffinose galactosyltransferase is an enzyme that catalyzes the chemical reaction

alpha-D-galactosyl-(1→3)-1D-myo-inositol + raffinose

\rightleftharpoons myo-inositol + stachyose

Thus, the two substrates of this enzyme are α-D-galactosyl-(1→3)-1D-myo-inositol and raffinose, whereas its two products are myo-inositol and stachyose.

This enzyme participates in galactose metabolism.

Nomenclature

This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is alpha-D-galactosyl-(1→3)-myo-inositol:raffinose galactosyltransferase. Other names in common use include galactinol-raffinose galactosyltransferase, and stachyose synthetase.

References

• Tanner W . 1967 . Die Biosynthese der Stachyose . Ber. Dtsch. Bot. Ges. . 80 . 111 .
• Tanner W, Kandler O . 1968 . Myo-inositol, a cofactor in the biosynthesis of stachyose . Eur. J. Biochem. . 4 . 233 - 9 . 5655499 . 10.1111/j.1432-1033.1968.tb00199.x . 2 . free .
• Lehle L, Tanner W . 1973 . The function of myo-inositol in the biosynthesis of raffinose Purification and characterization of galactinol:sucrose 6-galactosyltransferase from Vicia faba seeds . Eur. J. Biochem. . 38 . 103 - 10 . 4774118 . 10.1111/j.1432-1033.1973.tb03039.x . 1 . free .
• Preiss, J. (Ed.), The Biochemistry of Plants, vol. 3, Academic Press, New York, 1980, p. 221-270.