Understanding the biosynthesis and arrangement of the polymers in the intact plant cell wall provides indispensable insights for manufacturing processes which rely on plant biomass as a feedstock. Additionally, the production of engineered biomass that performs in a predictable way is reliant on an accurate understanding of the cell wall architecture. Application of multi-dimensional solid-state NMR (ssNMR) methods, which require no destructive sample preparation, allows investigation of the organization and interactions between the major biopolymers (i.e., polysaccharides and lignin) within intact, untreated, cell walls. Here, by successfully generating mature plants, including Arabidopsis, sorghum, switchgrass and poplar, with high <sup>13</sup>C incorporation (&gt;90 %) in a customized growth chamber, we employed a series of ssNMR experiments (e.g., refocused INADEQUATE, PDSD, T1 relaxation measurements) to investigate the arrangement of biopolymers in the native secondary cell wall of these plants and understand the architecture of their intact cell walls. Then, using the plants engineered to have altered biomass, we tested the effects of these modifications. Using these data, we propose updated models of the secondary cell wall of these key model and biomass species. These include the role of pectic side chains in Arabidopsis secondary cell walls (1), a new configuration of cellulose-xylan interaction in sorghum secondary cell wall (2), and the low recalcitrance of engineered low pectin switchgrass secondary cell wall (3), which will provide insights for future plant engineering strategies.

Employing multi-dimensional solid-state NMR to elucidate the architecture of native plant cell walls

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.