Skip to main content
SLU publication database (SLUpub)

Research article2015Peer reviewed

Glucuronic acid in Arabidopsis thaliana xylans carries a novel pentose substituent

Chong, Sun-Li; Koutaniemi, Sanna; Juvonen, Minna; Derba-Maceluch, Marta; Mellerowicz, Ewa; Tenkanen, Maija

Abstract

Glucuronic acids in Arabidopsis thaliana xylans exist in 4-O-methylated (MeGlcA) and non-methylated (GlcA) forms at a ratio of about 3:2. The matrix-assisted laser desorption/ionization mass spectrometry analysis of the endoxylanase liberated acidic oligosaccharides from the Arabidopsis inflorescence stem showed that two peaks with GlcA (GlcA-Xyl(4)Ac(1) and GlcA-Xyl(5)Ac(2)) had abnormally high intensities, as well as different tandem mass spectra, than their 4-O-methylated counterparts. These peaks were interestingly enriched in the xylan biosynthesis mutant irx7 and irx9-1. Multi-stages fragmentation analysis using negative ion electrospray-ion trap mass spectrometry indicated that this GlcA was further carrying a pentose residue in the glucuronoxylan-derived oligosaccharide from irx9-1. The structure was also identified in Arabidopsis wild type. The results prove evidence of a new pentose substitution on the GlcA residue of Arabidopsis GX, which is likely present in the primary walls. (C) 2015 Elsevier B.V. All rights reserved.

Keywords

Arabidopsis thaliana; Glucuronoxylan; Tandem mass spectrometry

Published in

International Journal of Biological Macromolecules
2015, Volume: 79, pages: 807-812
Publisher: ELSEVIER SCIENCE BV