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An Energy Frontiers Research Center Supported by the US Department of Energy, Office of Basic Energy Sciences

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An Energy Frontiers Research Center Supported by the US Department of Energy, Office of Basic Energy Sciences Center for Lignocellulose Structure and Formation An Energy Frontiers Research Center supported by the US Department of Energy, Office of Basic Energy Sciences Collaborative, integrated transdisciplinary research CLSF Mission The CLSF brings together unique expertise to reveal how plants construct their cell walls. Our goals are to discover how cellulose microfibrils are synthesized in diverse To develop a nano-scale understanding of the structure and formation of lignocellulose, the main structural material in plants, forms and how plant cell wall properties, including recalcitrance, emerge from forming a foundation for significant advances in sustainable energy and materials. interactions and assembly of cell wall polymers. CLSF Lead Institution Theme 1: How plants make cellulose: Theme 2: How plants assemble multi-functional cell walls: •Structure and function of cellulose synthase (CESA) •Mesoscale architecture of the cell wall Merge •Structure and function of cellulose synthesis complex (CSC) •Polymer interactions and conformations •Regulation of CSC activity and cellulose fibril formation •NMR of primary and secondary walls, including grasses •Matrix polymer delivery Height •Mobility of water, polysaccharides and proteins in the wall Modulus Partner Institutions •Coarse grain model of the primary cell wall •Macrofibril formation and lignification (secondary cell walls) •Spectral analysis of cell wall structure Architecture of the cell wall: AFM Wild type control Xyloglucan-deficient mutant analyses indicate rigid non-fibrillar Deformation and unsupported fibrillar regions QM/MM analysis provides the first theoretical model of the with areas of high Chemical structures of D-glucose, glucan chain and mechanism by which cellulose synthase elongates a cellulose adhesion in both cross section of cellulose microfibril (Kim 2013) polymer one glucosyl moiety at a time (Yang et al. 2015) Adhesion (T Zhang, D Cosgrove, PSU) Plant CESA Mesoscale architecture of cell wall: Lack of xyloglucan shows enhanced alignment of cellulose as imaged with FESEM (Y Zheng, C Anderson, D Cosgrove, PSU) Ab initio model of Director ATCESA1catD trimer Daniel J. Cosgrove (Biology, PSU) overlaid with ROSETTA model. P- Associate Director Current model Polymer interactions and conformations: Characterizing the CR and CSR regions 20 nm 20 nm NMR of primary and secondary walls, including Candace Haigler (Crop Sci & Plant Bio, NCSU) for the CSC as a association between glucuronoarabinoxylan and cellulose in the are shown in green grasses: Proposed locations of different cellulose forms Modern image analysis is used to hexamer of CESA plant cell wall (S Smith, L Petridis, D Cosgrove, ORNL and PSU) Senior Investigators in the plant cell wall microfibril (T Wang, M Hong, MIT) and olive spheres determine number and arrangement hetero-trimers Charles T. Anderson (Biology, PSU) (H O’Neill, ORNL) of CESAs in CSCs: Trimer of Pp TMH Bacterial CESA (Hill et al. 2014) Ying Gu (Biochem & Mol Biol, PSU) region is consistent with proven Seong Kim (Chem Eng, PSU) Structure prediction of individual CESAs trimers of cytosolic domain of AtCESA Matrix polymer delivery: Coarse grain model of the James Kubicki (Geosciences, PSU) (Y Yingling, NCSU) (BT Nixon, H O’Neill, C Haigler, PSU, Alkynyl fucose clickable probes plant cell wall: Microfibril Manish Kumar (Chem Eng, PSU) ORNL and NCSU) for metabolic labeling and beads in exemplary Janna Maranas (Chem Eng, PSU) fluorescence imaging of simulations: color-coded by Karl Mueller (Chemistry, PSU) the position along the Z-axis B. Tracy Nixon (Biochem & Mol Biol, PSU) Coarse grained polysaccharides (pectin) in cell Atomistic structure of a single unit representation of walls (D McClosky, C Anderson, (M Kowilak, J Maranas, PSU) Ming Tien (Biochem & Mol Biol, PSU) of plant cellulose synthase cellulose synthase Yara Yingling (Materials Sci & Eng, NCSU) in the membrane PSU, and R Dalrymple, Zeiss) complex Alison Roberts (Biol Sciences, URI) Hugh O’Neill (Biol & Soft Matter, ORNL) Jochen Zimmer (Mol Physiol & Biol Physics, UVA) Mei Hong (Chemistry, MIT) Control G – coniferyl alcohol S – sinapyl alcohol Advisory Board: Rajai Atalla (Cellulose International) John Brady (Cornell University) Vincent Bulone (Swedish Royal IT / Biomime) Michael Jarvis (University of Glasgow) Debra Mohnen (University of Georgia, DOE-BESC) Pore organization of Markus Pauly (University of California, Berkeley) bacterial cellulose John Ralph (University of Wisconsin, DOE-GLBRC) synthase subunit BcsA Lignification (secondary cell walls): Incorporation of different with cellulose chain In silico models of plant CSC structure and cellulose Putative interaction of cellulose monolignols in Arabidopsis stem sections (S Kiemle, D Cosgrove, Poster prepared by Laura Ullrich (PSU) (Bi et al. 2015) microfibril formation (Y Yingling, NCSU) synthase interactive protein1 PSU) Spectral analysis of cell wall structure: SFG (Sum (CSI1) with CSC complex and Frequency Generation) spectra of cellulose in biological Supported under Award # DE-SC0001090 from microtubule (Lei et al. 2015) tissues (Lee et al. 2014) the Office of Science, Basic Energy Sciences .
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