Lactosylceramide 4-alpha-galactosyltransferase explained

lactosylceramide 4-alpha-galactosyltransferase
Ec Number:	2.4.1.228
Cas Number:	52725-57-2
Go Code:	0050512

In enzymology, a lactosylceramide 4-alpha-galactosyltransferase is an enzyme that catalyzes the chemical reaction

UDP-galactose + beta-D-galactosyl-(1->4)-D-glucosylceramide

\rightleftharpoons UDP + alpha-D-galactosyl-(1->4)-beta-D-galactosyl-(1->4)-D- glucosylceramide

Thus, the two substrates of this enzyme are UDP-galactose and beta-D-galactosyl-(1->4)-D-glucosylceramide, whereas its 3 products are UDP, alpha-D-galactosyl-(1->4)-beta-D-galactosyl-(1->4)-D-, and glucosylceramide.

This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-galactose:lactosylceramide 4II-alpha-D-galactosyltransferase. Other names in common use include Galbeta1-4Glcbeta1-Cer alpha1,4-galactosyltransferase, globotriaosylceramide/CD77 synthase, and histo-blood group Pk UDP-galactose. This enzyme participates in glycosphingolipid biosynthesis - globoseries and glycan structures - biosynthesis 2.

References

• Bailly P, Piller F, Cartron JP, Leroy Y, Fournet B . 1986 . Identification of UDP-galactose: lactose (lactosylceramide) alpha-4 and beta-3 galactosyltransferases in human kidney . Biochem. Biophys. Res. Commun. . 141 . 84 - 91 . 3099784 . 10.1016/S0006-291X(86)80338-2 . 1 .
• Nilsson Sojka B, Bennett EP, Jersild C, Clausen H . 2000 . Cloning and expression of the histo-blood group Pk UDP-galactose: Ga1beta-4G1cbeta1-cer alpha1, 4-galactosyltransferase. Molecular genetic basis of the p phenotype . J. Biol. Chem. . 275 . 16723 - 9 . 10747952 . 10.1074/jbc.M000728200 . 22 . free .
• Suzuki Y, Urano T, Ohta M, Furukawa K . 2000 . Molecular cloning of globotriaosylceramide/CD77 synthase, a glycosyltransferase that initiates the synthesis of globo series glycosphingolipids . J. Biol. Chem. . 275 . 15152 - 6 . 10748143 . 10.1074/jbc.M909620199 . 20 . free .