Xylan Structure and Dynamics in Native <i>Brachypodium</i> Grass Cell Walls Investigated by Solid-State NMR Spectroscopy

The polysaccharide composition and dynamics of the intact stem leaf cell walls model grass Brachypodium distachyon are investigated to understand how developmental stage affects structure walls. 13C enrichment entire plant allowed detailed analysis xylan structure, side-chain functionalization, dynamics, interaction with cellulose using magic-angle-spinning solid-state NMR spectroscopy. Quantitative one-dimensional spectra two-dimensional 13C–13C correlation indicate that contain less pectic polysaccharides compared previously studied seedling primary Between leaf, secondary wall-rich contains more leaf. Moreover, chains about twofold acetylated 60% ferulated in stem. These highly adopt a conformation prevalently interact extensively cellulose. results support notion is found screw conformation, which preferentially binds This turn promotes cellulose–lignin interactions essential for formation wall.