A 13C three-dimensional DQ-SQ-SQ correlation experiment for high-resolution analysis of complex carbohydrates using solid-state NMR

Complex carbohydrates are the key components of the protective cell walls of microbial pathogens and the bioenergy reservoir in plants and algae. Structural characterization of these polymorphic molecules requires assistance from multidimensional C-13 correlation approaches. To facilitate the analysis of carbohydrate structure using solid-state NMR, we present a three-dimensional (3D) C-13-C-13-C-13 experiment that includes a double-quantum (DQ) dimension and is thus free of the cube's body diagonal. The enhanced resolution supports the unambiguous resonance assignment of many polysaccharides in plant and fungal cell walls using uniformly C-13-labeled cells of spruce and Aspergillus fumigatus. Long-range structural restraints were effectively obtained to revisit our understanding of the spatial organization of plant cellulose microfibrils. The method is widely applicable to the investigations of cellular carbohydrates and carbon-based biomaterials. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

The study presents a new method for analyzing the structure of carbohydrates using solid-state NMR. The method provides high resolution and allows for accurate resonance assignment of polysaccharides in plant and fungal cell walls using uniformly labeled cells. Long-range structural restraints can be obtained, which contributes to a better understanding of the spatial organization of plant cellulose microfibrils. The method has broad applications in the study of cellular carbohydrates and carbon-based biomaterials.