Multidimensional solid-state NMR studies of the structure and dynamics of pectic polysaccharides in uniformly C-13-labeled Arabidopsis primary cell walls

TitleMultidimensional solid-state NMR studies of the structure and dynamics of pectic polysaccharides in uniformly C-13-labeled Arabidopsis primary cell walls
Publication TypeJournal Article
Year of Publication2012
AuthorsDick-Perez M, Wang T, Salazar A, Zabotina OA, Hong M
Journal TitleMagnetic Resonance in Chemistry
Volume50
Pages539-550
Date Published08
Type of ArticleArticle
ISBN Number0749-1581
Accession NumberWOS:000306512400004
Keywordsadhesion, biosynthesis, cellulose, growth, molecular-structure, pectic polysaccharides, plants, RESONANCE, solid-state nmr, spectroscopy, thaliana, xyloglucan
Abstract

Plant cell wall (CW) polysaccharides are responsible for the mechanical strength and growth of plant cells; however, the high-resolution structure and dynamics of the CW polysaccharides are still poorly understood because of the insoluble nature of these molecules. Here, we use 2D and 3D magic-angle-spinning (MAS) solid-state NMR (SSNMR) to investigate the structural role of pectins in the plant CW. Intact and partially depectinated primary CWs of Arabidopsis thaliana were uniformly labeled with 13C and their NMR spectra were compared. Recent C-13 resonance assignment of the major polysaccharides in Arabidopsis thaliana CWs allowed us to determine the effects of depectination on the intermolecular packing and dynamics of the remaining wall polysaccharides. 2D and 3D correlation spectra show the suppression of pectin signals, confirming partial pectin removal by chelating agents and sodium carbonate. Importantly, higher cross peaks are observed in 2D and 3D 13C spectra of the depectinated CW, suggesting higher rigidity and denser packing of the remaining wall polysaccharides compared with the intact CW. 13C spinlattice relaxation times and 1H rotating-frame spinlattice relaxation times indicate that the polysaccharides are more rigid on both the nanosecond and microsecond timescales in the depectinated CW. Taken together, these results indicate that pectic polysaccharides are highly dynamic and endow the polysaccharide network of the primary CW with mobility and flexibility, which may be important for pectin functions. This study demonstrates the capability of multidimensional SSNMR to determine the intermolecular interactions and dynamic structures of complex plant materials under near-native conditions. Copyright (c) 2012 John Wiley & Sons, Ltd.

URL<Go to ISI>://WOS:000306512400004
DOI10.1002/mrc.3836
Alternate JournalMagn. Reson. Chem.