title: Plant biomass recalcitrance: effect of hemicellulose composition on nanoscale forces that control cell wall strength.
abstract: Efficient conversion of lignocellulosic biomass to second-generation biofuels and valuable chemicals requires decomposition of resilient plant cell wall structure. Cell wall recalcitrance varies among plant species and even phenotypes, depending on the chemical composition of the noncellulosic matrix. Changing the amount and composition of branches attached to the hemicellulose backbone can significantly alter the cell wall strength and microstructure. We address the effect of hemicellulose composition on primary cell wall assembly forces by using the 3D-RISM-KH molecular theory of solvation, which provides statistical-mechanical sampling and molecular picture of hemicellulose arrangement around cellulose. We show that hemicellulose branches of arabinose, glucuronic acid, and especially glucuronate strengthen the primary cell wall by strongly coordinating to hydrogen bond donor sites on the cellulose surface. We reveal molecular forces maintaining the cell wall structure and provide directions for genetic modulation of plants and pretreatment design to render biomass more amenable to processing.
authors.affiliation: National Institute for Nanotechnology , 11421 Saskatchewan Drive, Edmonton, Alberta, T6G 2M9, Canada.
authors.forename: Rodrigo L
authors.initials: RL
authors.lastname: Silveira
authors.forename: Stanislav R
authors.initials: SR
authors.lastname: Stoyanov
authors.forename: Sergey
authors.initials: S
authors.lastname: Gusarov
authors.forename: Munir S
authors.initials: MS
authors.lastname: Skaf
authors.forename: Andriy
authors.initials: A
authors.lastname: Kovalenko
mesh_terms: D001089:Arabinose / Q000737:chemistry; D018533:Biomass; D002473:Cell Wall / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D036103:Nanotechnology; D010944:Plants / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D011134:Polysaccharides; C007916:hemicellulose; D020723:Glucuronic Acid; D001089:Arabinose