PLANT PHYSIOLOGY , Vol 113, Issue 4 1265-1272, Copyright © 1997 by American Society of Plant Biologists
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BIOCHEMISTRY AND ENZYMOLOGY |
O-Acetylated Oligosaccharides from Pectins of Potato Tuber Cell Walls
T. Ishii
Forestry and Forest Products Research Institute, P.O. Box 16, Tsukuba Norin Kenkyu Danchinai, Ibaraki 305, Japan
Acetylated trigalacturonides and rhamnogalacturonan I (RG-I)-derived
oligosaccharides were isolated from a Driselase digest of potato tuber cell
walls by ion-exchange and size-exclusion chromatography. The
oligosaccharides were structurally characterized by fast atom
bombardment-mass spectroscopy, nuclear magnetic resonance spectroscopy, and
glycosyl-linkage composition analysis. One trigalacturonide contained a
single acetyl group at O-3 of the reducing galacturonic acid residue. A
second trigalacturonide contained two acetyl substituents, which were
located on O-3 or O-4 of the nonreducing galacturonic acid residue and O-3
of the reducing galacturonic acid residue. RG-I backbone-derived oligomers
had acetyl groups at O-2 of the galacturonic acid residues. Some of these
galacturonic acid residues were O-acetylated at both O-2 and O-3 positions.
Rhamnosyl residues of RG-I oligomers were not acetylated.