Skip to main content
Dryad

NMR data for RG-I isolated from Arabidopsis thaliana siliques

Data files

Sep 01, 2025 version files 248.98 MB

Click names to download individual files

Abstract

Pectin is generally divided into four distinct structural categories, namely homogalacturonan, xylogalacturonan, rhamnogalacturonan I (RG-I), and rhamnogalacturonan II. While much of the structural diversity of homogalacturonan, xylogalacturonan, and rhamnogalacturonan II has been elucidated, the structural features of RG-I are less well understood. In this work, we employed multiple complementary analytical techniques to present a detailed structural analysis of RG-I in the model system Arabidopsis thaliana. Starting with highly purified RG-I from different Arabidopsis tissues, we employed comparative linkage and NMR analysis along with mass spectrometry analysis of enzymatically digested RG-I oligosaccharides. Besides the presence of the canonical 5-arabinan, 4-galactan, 6-galactan, and arabino-galactan RG-I side chains of varying lengths, we show that a large portion of the 6-galactan is terminated by either 4-O-methyl β-GlcA residues or, to a smaller degree, β-GlcA that lacks the Me-ether group. Importantly, O-acetylation of RG-I GalA residues is a minor modification, while 10% of the backbone Rha residues are 3-O-acetylated, and most of the acetylated Rha additionally branches with β-Gal side chain. Taken together, the combined results of these different analytical techniques present the most comprehensive structural overview of Arabidopsis thaliana RG-I to date.