The N-acetyl-binding pocket of N-acetylglucosaminyltransferases also accommodates a sugar analog with a chemical handle at C2.
Glycobiology
; 22(3): 379-88, 2012 Mar.
Article
in En
| MEDLINE
| ID: mdl-21868414
ABSTRACT
In recent years, sugars with a unique chemical handle have been used to detect and elucidate the function of glycoconjugates. Such chemical handles have generally been part of an N-acetyl moiety of a sugar. We have previously developed several applications using the single mutant Y289L-ß1,4-galactosyltransferase I (Y289L-ß4Gal-T1) and the wild-type polypeptide-α-GalNAc-T enzymes with UDP-C2-keto-Gal. Here, we describe for the first time that the GlcNAc-transferring enzymes-R228K-Y289L-ß4Gal-T1 mutant enzyme, the wild-type human ß1,3-N-acetylglucosaminyltransferase-2 and human Maniac Fringe-can also transfer the GlcNAc analog C2-keto-Glc molecule from UDP-C2-keto-Glc to their respective acceptor substrates. Although the R228K-Y289L-ß4Gal-T1 mutant enzyme transfers the donor sugar substrate GlcNAc or its analog C2-keto-Glc only to its natural acceptor substrate, GlcNAc, it does not transfer to its analog C2-keto-Glc. Thus, these observations suggest that the GlcNAc-transferring glycosyltransferases can generally accommodate a chemical handle in the N-acetyl-binding cavity of the donor sugar substrate, but not in the N-acetyl-binding cavity of the acceptor sugar.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
N-Acetylglucosaminyltransferases
/
Intracellular Signaling Peptides and Proteins
/
Galactose
/
Hexosyltransferases
/
Membrane Proteins
Type of study:
Prognostic_studies
Language:
En
Journal:
Glycobiology
Journal subject:
BIOQUIMICA
Year:
2012
Type:
Article
Affiliation country:
United States