Biology:Beta-galactoside alpha-2,3-sialyltransferase

From HandWiki
Short description: Enzyme
beta-galactoside alpha-2,3-sialyltransferase
Identifiers
EC number2.4.99.4
CAS number71124-51-1
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO

In enzymology, a beta-galactoside alpha-2,3-sialyltransferase (EC 2.4.99.4) is an enzyme that catalyzes the chemical reaction

CMP-N-acetylneuraminate + beta-D-galactosyl-1,3-N-acetyl-alpha-D-galactosaminyl-R [math]\displaystyle{ \rightleftharpoons }[/math] CMP + alpha-N-acetylneuraminyl-2,3-beta-D-galactosyl-1,3-N-acetyl-alpha-D- galactosaminyl-R

Thus, the two substrates of this enzyme are CMP-N-acetylneuraminate and beta-D-galactosyl-1,3-N-acetyl-alpha-D-galactosaminyl-R, whereas its 3 products are CMP, alpha-N-acetylneuraminyl-2,3-beta-D-galactosyl-1,3-N-acetyl-alpha-D-, and galactosaminyl-R.

This enzyme belongs to the family of transferases, specifically those glycosyltransferases that do not transfer hexosyl or pentosyl groups. The systematic name of this enzyme class is CMP-N-acetylneuraminate:beta-D-galactoside alpha-2,3-N-acetylneuraminyl-transferase. This enzyme participates in 7 metabolic pathways: o-glycan biosynthesis, keratan sulfate biosynthesis, glycosphingolipid biosynthesis - lactoseries, glycosphingolipid biosynthesis - globoseries, glycosphingolipid biosynthesis - ganglioseries, glycan structures - biosynthesis 1, and glycan structures - biosynthesis 2.

Structural studies

As of late 2007, 9 structures have been solved for this class of enzymes, with PDB accession codes 2EX0, 2EX1, 2IHJ, 2IHK, 2IHZ, 2II6, 2IIB, 2IIQ, and 2ILV.

References

  • "Enzymatic characterization of beta D-galactoside alpha2 leads to 3 sialyltransferase from porcine submaxillary gland". J. Biol. Chem. 254 (11): 4444–51. 1979. PMID 438198. 
  • "Purification to homogeneity of a beta-galactoside alpha2 leads to 3 sialyltransferase and partial purification of an alpha-N-acetylgalactosaminide alpha2 leads to 6 sialyltransferase from porcine submaxillary glands". J. Biol. Chem. 254 (11): 4434–42. 1979. PMID 438196.