Which of the following enzymes is NOT involved in blood group antigen synthesis?
Blood group oligosaccharide construction depends nucleotide sugar utilizing glycosyltransferases retaining mechanism not phosphoinositide hydrolyzing enzymes that cleave glycerophosphate bonds. Formation H requires GDP fucose dependent FUT1 FUT2 FUT2 secretor adding fucose alpha one two linkage Gal. Conversion A uses UDP GalNAc dependent alpha one three N acetylgalactosaminyltransferase GTA adding GalNAc, B uses UDP Gal dependent galactosyltransferase GTB adding galactose both GT6 family retaining via SNi like mechanism. These catalyze glycosidic bond formation with retention stereochemistry r
Ref: Patenaude et al., Transfusion 2002, ABO synthetic enzymes versus phospholipase C role distinction.
