ジャーナル: Biomacromolecules / 年: 2022 タイトル: Structure of -Synthesized Cellulose Fibrils Viewed by Cryo-Electron Tomography and C Natural-Abundance Dynamic Nuclear Polarization Solid-State NMR. 著者: Fabien Deligey / Mark A Frank / Sung Hyun Cho / Alex Kirui / Frederic Mentink-Vigier / Matthew T Swulius / B Tracy Nixon / Tuo Wang / 要旨: Cellulose, the most abundant biopolymer, is a central source for renewable energy and functionalized materials. synthesis of cellulose microfibrils (CMFs) has become possible using purified ...Cellulose, the most abundant biopolymer, is a central source for renewable energy and functionalized materials. synthesis of cellulose microfibrils (CMFs) has become possible using purified cellulose synthase (CESA) isoforms from and hybrid aspen. The exact nature of these fibrils remains unknown. Here, we characterize -synthesized fibers made by CESAs present in membrane fractions of over-expressing CESA5 by cryo-electron tomography and dynamic nuclear polarization (DNP) solid-state NMR. DNP enabled measuring two-dimensional C-C correlation spectra without isotope-labeling of the fibers. Results show structural similarity between fibrils and native CMF in plant cell walls. Intensity quantifications agree with the 18-chain structural model for plant CMF and indicate limited fibrillar bundling. The system thus reveals insights into cell wall synthesis and may contribute to novel cellulosic materials. The integrated DNP and cryo-electron tomography methods are also applicable to structural studies of other carbohydrate-based biomaterials.