Dimers of a GFG hexasaccharide occur in apple fruit xyloglucan.
Apple fruit xyloglucan is predominantly built up from XXXG, XXFG, and XLFG units (G = beta-D-Glcp-, X = alpha-D-Xylp-(1-->6)-beta-D-Glcp-, L = beta-D-Galp-(1-->2)-alpha-D-Xylp-(1-->6)-beta-D-Glcp-, F = alpha-L-Fucp-(1-->2)-beta-D-Galp-(1-->2)-alpha-D-Xyl p-(1-->6)-beta-D-Glcp-). However, small amounts of oligosaccharides with a less heavily branched glucan backbone also occur. Structural analysis of two such oligosaccharides, isolated from a xyloglucan preparation digested with endoglucanase i.v., using a combination of FAB mass spectrometry and 1H NMR spectroscopy, afforded the identification of GFG and a dimer of GFG. The finding of the dodecasaccharide GFGGFG as a structural element of apple fruit xyloglucan is most unusual.
Spronk
B A
BA
Department of Bio-Organic Chemistry, Utrecht University, Netherlands.
Rademaker
G J
GJ
Haverkamp
J
J
Thomas-Oates
J E
JE
Vincken
J P
JP
Voragen
A G
AG
Kamerling
J P
JP
Vliegenthart
J F
JF
D002240:Carbohydrate Sequence; D019281:Dimerization; D008401:Gas Chromatography-Mass Spectrometry; D005936:Glucans; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D009844:Oligosaccharides / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D011522:Protons; D019685:Rosales / Q000737:chemistry*; D017421:Sequence Analysis; D014990:Xylans
D005936:Glucans; D009844:Oligosaccharides; D011134:Polysaccharides; D011522:Protons; D014990:Xylans; C029353:xyloglucan