J. Biol. Chem., Vol. 261, Issue 26, 12000-12005, Sep, 1986
Transfer of glycerol by Endo-beta-N-acetylglucosaminidase F to oligosaccharides during chitobiose core cleavage
RB Trimble, PH Atkinson, AL Tarentino, TH Plummer Jr, F Maley and KB Tomer
N-Linked oligosaccharides, when hydrolyzed by glycerol-containing
preparations of endo-beta-N-acetylglucosaminidase (Endo) F from
Flavobacterium meningosepticum were found to have glycerol attached to
their reducing ends. The absence of a reducing end was confirmed by
high-field 1H NMR spectroscopy, and the incorporated glycerol was verified
through mass spectrometry and collisionally activated decomposition fast
atom bombardment/mass spectrometry/mass spectrometry techniques. Periodate
oxidation of [1(3)-14C]glycerol-labeled oligosaccharides indicated glycerol
was glycosidically linked via its 1(3) carbon to the C1 of the reducing end
N-acetylglucosamine. In a second, less favored reaction, the glycerol
glycoside was hydrolyzed by Endo F using water as the terminal nucleophile,
thus regenerating the N- acetylglucosamine reducing end. Glycerol could be
removed from Endo F preparations without affecting enzyme stability, and
chitobiosyl core hydrolysis in its absence provided intact oligosaccharides
with normal N-acetylglucosamine reducing ends. The incorporation of labeled
glycerol may provide a useful method for monitoring of Endo F release of
oligosaccharides.