51
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Majidi R, Taghiyari HR, Abdolmaleki D. Molecular Dynamics Simulation Evaluating the Hydrophilicity of Nanowollastonite on Cellulose. J STRUCT CHEM+ 2019. [DOI: 10.1134/s0022476619090178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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52
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Kinetics of Water Vapor Sorption in Wood Cell Walls: State of the Art and Research Needs. FORESTS 2019. [DOI: 10.3390/f10080704] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Water vapor sorption is the most fundamental aspect of wood-moisture relations. It is directly or indirectly related to the physical properties of wood and the onset of wood-damage mechanisms. While sorption properties of cellulosic materials have been utilized since antiquity, the time-dependent transition from one moisture content to another (i.e., sorption kinetics) has received much less attention. In this critical review, we present the state-of-the-art of water vapor sorption kinetics in wood. We first examine different experimental methods that have been used to measure sorption kinetics, from the quartz helix vacuum balance beginning in earnest in the 1930s, to automated sorption balances used recently. We then give an overview of experimental observations and describe the physical phenomena that occur during the sorption process, which potentially govern the following kinetics: boundary layer mass transfer resistance, heat of sorption, cell wall diffusion, swelling, and polymer mobility. Finally, we evaluate theoretical models that have been proposed for describing sorption kinetics, considering both experimental data and the physical processes described in the previous section. It is clear that no previously developed model can phenomenologically describe the sorption process. Instead, new models are needed. We conclude that the development of new models will require more than simple gravimetric measurements. In addition to mass changes, complementary techniques are needed to probe other important physical quantities on multiple length scales.
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53
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Rodriguez Quiroz N, Norton AM, Nguyen H, Vasileiadou E, Vlachos DG. Homogeneous Metal Salt Solutions for Biomass Upgrading and Other Select Organic Reactions. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01853] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Natalia Rodriguez Quiroz
- Catalysis Center for Energy Innovation and Department of Chemical and Biomolecular Engineering, University of Delaware, 221 Academy Street, Newark, Delaware 19716, United States
| | - Angela M. Norton
- Catalysis Center for Energy Innovation and Department of Chemical and Biomolecular Engineering, University of Delaware, 221 Academy Street, Newark, Delaware 19716, United States
| | - Hannah Nguyen
- Catalysis Center for Energy Innovation and Department of Chemical and Biomolecular Engineering, University of Delaware, 221 Academy Street, Newark, Delaware 19716, United States
| | - Efterpi Vasileiadou
- Catalysis Center for Energy Innovation and Department of Chemical and Biomolecular Engineering, University of Delaware, 221 Academy Street, Newark, Delaware 19716, United States
| | - Dionisios G. Vlachos
- Catalysis Center for Energy Innovation and Department of Chemical and Biomolecular Engineering, University of Delaware, 221 Academy Street, Newark, Delaware 19716, United States
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54
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Wood–Moisture Relationships Studied with Molecular Simulations: Methodological Guidelines. FORESTS 2019. [DOI: 10.3390/f10080628] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This paper aims at providing a methodological framework for investigating wood polymers using atomistic modeling, namely, molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) simulations. Atomistic simulations are used to mimic water adsorption and desorption in amorphous polymers, make observations on swelling, mechanical softening, and on hysteresis. This hygromechanical behavior, as observed in particular from the breaking and reforming of hydrogen bonds, is related to the behavior of more complex polymeric composites. Wood is a hierarchical material, where the origin of wood-moisture relationships lies at the nanoporous material scale. As water molecules are adsorbed into the hydrophilic matrix in the cell walls, the induced fluid–solid interaction forces result in swelling of these cell walls. The interaction of the composite polymeric material, that is the layer S2 of the wood cell wall, with water is known to rearrange its internal material structure, which makes it moisture sensitive, influencing its physical properties. In-depth studies of the coupled effects of water sorption on hygric and mechanical properties of different polymeric components can be performed with atomistic modeling. The paper covers the main components of knowledge and good practice for such simulations.
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55
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Ciesielski PN, Wagner R, Bharadwaj VS, Killgore J, Mittal A, Beckham GT, Decker SR, Himmel ME, Crowley MF. Nanomechanics of cellulose deformation reveal molecular defects that facilitate natural deconstruction. Proc Natl Acad Sci U S A 2019; 116:9825-9830. [PMID: 31036649 PMCID: PMC6525519 DOI: 10.1073/pnas.1900161116] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Technologies surrounding utilization of cellulosic materials have been integral to human society for millennia. In many materials, controlled introduction of defects provides a means to tailor properties, introduce reactivity, and modulate functionality for various applications. The importance of defects in defining the behavior of cellulose is becoming increasingly recognized. However, fully exploiting defects in cellulose to benefit biobased materials and conversion applications will require an improved understanding of the mechanisms of defect induction and corresponding molecular-level consequences. We have identified a fundamental relationship between the macromolecular structure and mechanical behavior of cellulose nanofibrils whereby molecular defects may be induced when the fibrils are subjected to bending stress exceeding a certain threshold. By nanomanipulation, imaging, and molecular modeling, we demonstrate that cellulose nanofibrils tend to form kink defects in response to bending stress, and that these macromolecular features are often accompanied by breakages in the glucan chains. Direct observation of deformed cellulose fibrils following partial enzymatic digestion reveals that processive cellulases exploit these defects as initiation sites for hydrolysis. Collectively, our findings provide a refined understanding of the interplay between the structure, mechanics, and reactivity of cellulose assemblies.
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Affiliation(s)
- Peter N Ciesielski
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401;
| | - Ryan Wagner
- Material Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO
| | - Vivek S Bharadwaj
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401
| | - Jason Killgore
- Material Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO
| | - Ashutosh Mittal
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401
| | - Gregg T Beckham
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401
| | - Stephen R Decker
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401
| | - Michael E Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401
| | - Michael F Crowley
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401;
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56
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Purington E, Bousfield D, Gramlich WM. Fluorescent Dye Adsorption in Aqueous Suspension to Produce Tagged Cellulose Nanofibers for Visualization on Paper. CELLULOSE (LONDON, ENGLAND) 2019; 26:5117-5131. [PMID: 31130782 PMCID: PMC6532663 DOI: 10.1007/s10570-019-02439-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
Cellulose nanofibers (CNFs) have great potential to be a layer in packaging materials because of their good barrier properties. When paper is coated with CNFs, they are difficult to distinguish from the base sheet. This issue creates challenges when trying to determine where CNFs migrate relative to the paper fibers during coating and drying. A three- dimensional analysis is possible by using confocal laser scanning microscopy (CLSM) if CNFs can be tagged with fluorescently active groups. In this study, CNFs were fluorescently tagged through adsorption of fluorescent dyes such as fluorescein isothiocyanate (FITC) and thioflavin by mixing with CNFs in their native suspension followed by purification. The adsorbed dye remained attached during typical coating procedures, low pH values, and high ionic strengths, but not for high pH and in contact with acetone. CNFs were also covalently tagged with FITC following methods reported in the literature as a comparison to already established methods for tagging cellulose nanocrystals (CNCs). Images of never dried samples indicated that covalently tagging CNFs altered the state of the fines dispersion, while dye adsorption did not. Coatings of the adsorbed dye tagged CNFs on paper were successfully imaged by CLSM since the concentration of dye in the water phase was low enough to provide a good contrast between regions of CNFs and paper. With this method, the location and potential migration of CNFs coated on paper were successfully determined for the first time to the best of our knowledge. CNF based coatings with solids larger than 2.8% were found to have a distinct layer of CNFs at the paper surface with little CNFs penetrating into the paper structure, but lower solids result in significant penetration into the paper.
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Affiliation(s)
- Emilia Purington
- Department of Chemical and Biological Engineering, Paper Surface Science Program, University of Maine, Orono, ME 04469
| | - Douglas Bousfield
- Department of Chemical and Biological Engineering, Paper Surface Science Program, University of Maine, Orono, ME 04469
| | - William M Gramlich
- Department of Chemistry, Paper Surface Science Program, University of Maine, Orono, ME 04469
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57
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Molecular insight into the wetting behavior and amphiphilic character of cellulose nanocrystals. Adv Colloid Interface Sci 2019; 267:15-25. [PMID: 30884357 DOI: 10.1016/j.cis.2019.02.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/27/2019] [Accepted: 02/27/2019] [Indexed: 02/05/2023]
Abstract
The study of nanocellulose is a field of growing interest due to its many applications and its use in the development of biocompatible and eco-friendly materials. In spite of the vast number of studies in the field, many questions about the role of the molecular structure in the properties of cellulose are still subject of debate. One of these fundamental questions is the possible amphiphilic nature of cellulose and the relative role of hydrogen bonding and hydrophobic effect on the interactions of cellulose. In this work we present an extensive molecular dynamics simulation study of this question by analyzing the wetting of cellulose with water and organic solvent, its interaction with hydrophilic and hydrophobic ions and its interaction with a protein (human epidermal growth factor, hEGF). We consider two characteristic cellulose crystal planes of Iβ cellulose with very different roughness, different hydrogen bonding capability and different exposure of cellulose hydrophobic groups (the (010) plane which has exposed -OH groups and the (100) plane with buried -OH groups). Our results show that both surfaces are simultaneously hydrophilic and lipophilic, with both surfaces having very similar contact angles. In spite of the global similarity of wetting of both surfaces, the molecular details of wetting are very different and substantial local wetting heterogeneities (which strongly depend on the surface) appear for both solvents. We also observe a weak interaction of both surfaces with hydrophobic and hydrophilic solutes. These weak interactions are attributed to the simultaneous lipophilic and hydrophilic character of both (100) and (010) cellulose surfaces. Interestingly, we found a substantial interaction of both cellulose planes with polar and apolar residues of the hEGF protein.
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58
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Stalker MR, Grant J, Yong CW, Ohene-Yeboah LA, Mays TJ, Parker SC. Molecular simulation of hydrogen storage and transport in cellulose. MOLECULAR SIMULATION 2019. [DOI: 10.1080/08927022.2019.1593975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- M. R. Stalker
- Centre for Sustainable Chemical Technologies, University of Bath, Bath, UK
- Department of Chemistry, University of Bath, Bath, UK
| | - J. Grant
- Department of Chemistry, University of Bath, Bath, UK
- Computing Services, University of Bath, Bath, UK
| | - C. W. Yong
- Scientific Computing Department, STFC Daresbury Laboratory, Daresbury, UK
| | - L. A. Ohene-Yeboah
- Centre for Sustainable Chemical Technologies, University of Bath, Bath, UK
- Department of Chemistry, University of Bath, Bath, UK
| | - T. J. Mays
- Department of Chemical Engineering, University of Bath, Bath, UK
| | - S. C. Parker
- Department of Chemistry, University of Bath, Bath, UK
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59
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Hamre AG, Kaupang A, Payne CM, Väljamäe P, Sørlie M. Thermodynamic Signatures of Substrate Binding for Three Thermobifida fusca Cellulases with Different Modes of Action. Biochemistry 2019; 58:1648-1659. [PMID: 30785271 DOI: 10.1021/acs.biochem.9b00014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The enzymatic breakdown of recalcitrant polysaccharides is achieved by synergistic enzyme cocktails of glycoside hydrolases (GHs) and accessory enzymes. Many GHs are processive, meaning that they stay bound to the substrate between subsequent catalytic interactions. Cellulases are GHs that catalyze the hydrolysis of cellulose [β-1,4-linked glucose (Glc)]. Here, we have determined the relative subsite binding affinity for a glucose moiety as well as the thermodynamic signatures for (Glc)6 binding to three of the seven cellulases produced by the bacterium Thermobifida fusca. TfCel48A is exo-processive, TfCel9A endo-processive, and TfCel5A endo-nonprocessive. Initial hydrolysis of (Glc)5 and (Glc)6 was performed in H218O enabling the incorporation of an 18O atom at the new reducing end anomeric carbon. A matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the products reveals the intensity ratios of otherwise identical 18O- and 16O-containing products to provide insight into how the substrate is placed during productive binding. The two processive cellulases have significant binding affinity in subsites where products dissociate during processive hydrolysis, aligned with a need to have a pushing potential to remove obstacles on the substrate. Moreover, we observed a correlation between processive ability and favorable binding free energy, as previously postulated. Upon ligand binding, the largest contribution to the binding free energy is desolvation for all three cellulases as determined by isothermal titration calorimetry. The two endo-active cellulases show a more favorable solvation entropy change compared to the exo-active cellulase, while the two processive cellulases have less favorable changes in binding enthalpy compared to the nonprocessive TfCel5A.
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Affiliation(s)
- Anne Grethe Hamre
- Department of Chemistry, Biotechnology and Food Science , Norwegian University of Life Sciences , P.O. Box 5003, N-1432 Ås , Norway
| | - Anita Kaupang
- Department of Chemistry, Biotechnology and Food Science , Norwegian University of Life Sciences , P.O. Box 5003, N-1432 Ås , Norway
| | - Christina M Payne
- Department of Chemical and Materials Engineering , University of Kentucky , 177 F. Paul Anderson Tower , Lexington , Kentucky 40506 , United States
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology , University of Tartu , 50090 Tartu , Estonia
| | - Morten Sørlie
- Department of Chemistry, Biotechnology and Food Science , Norwegian University of Life Sciences , P.O. Box 5003, N-1432 Ås , Norway
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60
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Sahputra IH, Alexiadis A, Adams MJ. Effects of Moisture on the Mechanical Properties of Microcrystalline Cellulose and the Mobility of the Water Molecules as Studied by the Hybrid Molecular Mechanics-Molecular Dynamics Simulation Method. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/polb.24801] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Iwan H. Sahputra
- School of Chemical Engineering; University of Birmingham; Birmingham United Kingdom
| | - Alessio Alexiadis
- School of Chemical Engineering; University of Birmingham; Birmingham United Kingdom
| | - Michael J. Adams
- School of Chemical Engineering; University of Birmingham; Birmingham United Kingdom
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61
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Uncovering supercritical CO2 wood dewatering via interleaved 1H-imaging and 13C-spectroscopy with real-time reconstruction. J Supercrit Fluids 2019. [DOI: 10.1016/j.supflu.2018.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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62
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Bruel C, Tavares JR, Carreau PJ, Heuzey MC. The structural amphiphilicity of cellulose nanocrystals characterized from their cohesion parameters. Carbohydr Polym 2019; 205:184-191. [DOI: 10.1016/j.carbpol.2018.10.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 10/08/2018] [Accepted: 10/09/2018] [Indexed: 11/25/2022]
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63
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Arcari M, Zuccarella E, Axelrod R, Adamcik J, Sánchez-Ferrer A, Mezzenga R, Nyström G. Nanostructural Properties and Twist Periodicity of Cellulose Nanofibrils with Variable Charge Density. Biomacromolecules 2019; 20:1288-1296. [DOI: 10.1021/acs.biomac.8b01706] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mario Arcari
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
| | - Elena Zuccarella
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
| | - Robert Axelrod
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
| | - Jozef Adamcik
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
| | - Antoni Sánchez-Ferrer
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
| | - Raffaele Mezzenga
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
- ETH Zurich, Department of Materials, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland
| | - Gustav Nyström
- ETH Zurich, Department of Health Sciences and Technology, Schmelzbergstrasse 9, LFO E23, 8092, Zurich, Switzerland
- EMPA, Laboratory for Cellulose & Wood Materials, Überlandstrasse 129, 8600 Dübendorf, Switzerland
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64
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Morozova S, Schmidt PW, Bates FS, Lodge TP. Effect of Poly(ethylene glycol) Grafting Density on Methylcellulose Fibril Formation. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01899] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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65
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Molecular dynamics simulations of theoretical cellulose nanotube models. Carbohydr Polym 2018; 190:331-338. [PMID: 29628255 DOI: 10.1016/j.carbpol.2018.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 02/26/2018] [Accepted: 03/05/2018] [Indexed: 11/23/2022]
Abstract
Nanotubes are remarkable nanoscale architectures for a wide range of potential applications. In the present paper, we report a molecular dynamics (MD) study of the theoretical cellulose nanotube (CelNT) models to evaluate their dynamic behavior in solution (either chloroform or benzene). Based on the one-quarter chain staggering relationship, we constructed six CelNT models by combining the two chain polarities (parallel (P) and antiparallel (AP)) and three symmetry operations (helical right (HR), helical left (HL), and rotation (R)) to generate a circular arrangement of molecular chains. Among the four models that retained the tubular form (P-HR, P-HL, P-R, and AP-R), the P-R and AP-R models have the lowest steric energies in benzene and chloroform, respectively. The structural features of the CelNT models were characterized in terms of the hydroxymethyl group conformation and intermolecular hydrogen bonds. Solvent structuring more clearly occurred with benzene than chloroform, suggesting that the CelNT models may disperse in benzene.
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66
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Funahashi R, Ono Y, Tanaka R, Yokoi M, Daido K, Inamochi T, Saito T, Horikawa Y, Isogai A. Changes in the degree of polymerization of wood celluloses during dilute acid hydrolysis and TEMPO-mediated oxidation: Formation mechanism of disordered regions along each cellulose microfibril. Int J Biol Macromol 2018; 109:914-920. [DOI: 10.1016/j.ijbiomac.2017.11.078] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 10/09/2017] [Accepted: 11/12/2017] [Indexed: 10/18/2022]
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67
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Bomble YJ, Lin CY, Amore A, Wei H, Holwerda EK, Ciesielski PN, Donohoe BS, Decker SR, Lynd LR, Himmel ME. Lignocellulose deconstruction in the biosphere. Curr Opin Chem Biol 2017; 41:61-70. [DOI: 10.1016/j.cbpa.2017.10.013] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 10/09/2017] [Accepted: 10/10/2017] [Indexed: 12/18/2022]
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68
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Watermann T, Sebastiani D. Liquid Water Confined in Cellulose with Variable Interfacial Hydrophilicity. ACTA ACUST UNITED AC 2017. [DOI: 10.1515/zpch-2017-1011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
We investigate liquid water confined within nanoscale cellulose slabs by means of molecular dynamics simulations. Depending on the construction of the cellulose–water interface, two different surface structures with distinct levels of hydrophilicity are exposed to the water. The different philicities are reflected in the response of the water phase to this geometric confinement, both in terms of the density profile and in the strength of the aqueous hydrogen bonding network. At the smooth surface cut along the (010) axis of the cellulose crystal, water shows typical properties of a hydrophilic confinement: the density shows fluctuations that disappear further away from the wall, the water molecules orient themselves and the coordination numbers increases at the interface. As a consequence, the water becomes “harder” at the interface, with a considerably increased local ordering. At the zigzag-shaped surface along the (111) axis, the degree of hydrophilicity is reduced, and only small effects can be seen: the density shows weak fluctuations, and the orientation of the water molecules is closer to that of bulk water than to the smooth surface. The local coordination numbers remains constant over the whole confinement. Our work shows that the nature of the exposed cellulose interface has a strong influence on how the structure of adjacent water is modified. The different ways of surface construction yield distinct degrees of hydrophilicity and spatial accessibility regarding the hydrogen bond network, resulting in a notably different interfacial water structure.
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Affiliation(s)
- Tobias Watermann
- Institute of Chemistry , Martin-Luther University Halle-Wittenberg , 06120 Halle , Germany
| | - Daniel Sebastiani
- Institute of Chemistry , Martin-Luther University Halle-Wittenberg , von-Danckelmann-Platz 4 , 06120 Halle , Germany
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69
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Hassan L, Reppke MJ, Thieme N, Schweizer SA, Mueller CW, Benz JP. Comparing the physiochemical parameters of three celluloses reveals new insights into substrate suitability for fungal enzyme production. Fungal Biol Biotechnol 2017; 4:10. [PMID: 29119000 PMCID: PMC5669031 DOI: 10.1186/s40694-017-0039-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 10/23/2017] [Indexed: 11/30/2022] Open
Abstract
Background The industrial applications of cellulases are mostly limited by the costs associated with their production. Optimized production pathways are therefore desirable. Based on their enzyme inducing capacity, celluloses are commonly used in fermentation media. However, the influence of their physiochemical characteristics on the production process is not well understood. In this study, we examined how physical, structural and chemical properties of celluloses influence cellulase and hemicellulase production in an industrially-optimized and a non-engineered filamentous fungus: Trichoderma reesei RUT-C30 and Neurospora crassa. The performance was evaluated by quantifying gene induction, protein secretion and enzymatic activities. Results Among the three investigated substrates, the powdered cellulose was found to be the most impure, and the residual hemicellulosic content was efficiently perceived by the fungi. It was furthermore found to be the least crystalline substrate and consequently was the most readily digested cellulose in vitro. In vivo however, only RUT-C30 was able to take full advantage of these factors. When comparing carbon catabolite repressed and de-repressed strains of T. reesei and N. crassa, we found that cre1/cre-1 is at least partially responsible for this observation, but that the different wiring of the molecular signaling networks is also relevant. Conclusions Our findings indicate that crystallinity and hemicellulose content are major determinants of performance. Moreover, the genetic background between WT and modified strains greatly affects the ability to utilize the cellulosic substrate. By highlighting key factors to consider when choosing the optimal cellulosic product for enzyme production, this study has relevance for the optimization of a critical step in the biotechnological (hemi-) cellulase production process. Electronic supplementary material The online version of this article (10.1186/s40694-017-0039-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lara Hassan
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Manfred J Reppke
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Nils Thieme
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Steffen A Schweizer
- Chair of Soil Science, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Carsten W Mueller
- Chair of Soil Science, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - J Philipp Benz
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
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70
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Martínez-Sanz M, Pettolino F, Flanagan B, Gidley MJ, Gilbert EP. Structure of cellulose microfibrils in mature cotton fibres. Carbohydr Polym 2017; 175:450-463. [DOI: 10.1016/j.carbpol.2017.07.090] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 07/19/2017] [Accepted: 07/30/2017] [Indexed: 12/16/2022]
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71
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Atalla RH, Atalla RS, Agarwal UP. The Nanostructures of Native Celluloses, Their Transformations upon Isolation, and Their Implications for Production of Nanocelluloses. ACTA ACUST UNITED AC 2017. [DOI: 10.1021/bk-2017-1251.ch001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Affiliation(s)
- Rajai H. Atalla
- Cellulose Sciences International, 510 Charmany Drive, Ste. 259, Madison, Wisconsin 53719, United States
- University of Wisconsin, Madison, Wisconsin 53706, United States
- Forest Products Laboratory, USDA Forest Service, 1 Gifford Pinchot Drive, Madison, Wisconsin 53726, United States
| | - Rowan S. Atalla
- Cellulose Sciences International, 510 Charmany Drive, Ste. 259, Madison, Wisconsin 53719, United States
- University of Wisconsin, Madison, Wisconsin 53706, United States
- Forest Products Laboratory, USDA Forest Service, 1 Gifford Pinchot Drive, Madison, Wisconsin 53726, United States
| | - Umesh P. Agarwal
- Cellulose Sciences International, 510 Charmany Drive, Ste. 259, Madison, Wisconsin 53719, United States
- University of Wisconsin, Madison, Wisconsin 53706, United States
- Forest Products Laboratory, USDA Forest Service, 1 Gifford Pinchot Drive, Madison, Wisconsin 53726, United States
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72
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Kannam SK, Oehme DP, Doblin MS, Gidley MJ, Bacic A, Downton MT. Hydrogen bonds and twist in cellulose microfibrils. Carbohydr Polym 2017; 175:433-439. [PMID: 28917886 DOI: 10.1016/j.carbpol.2017.07.083] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/23/2017] [Accepted: 07/29/2017] [Indexed: 10/19/2022]
Abstract
There is increasing experimental and computational evidence that cellulose microfibrils can exist in a stable twisted form. In this study, atomistic molecular dynamics (MD) simulations are performed to investigate the importance of intrachain hydrogen bonds on the twist in cellulose microfibrils. We systematically enforce or block the formation of these intrachain hydrogen bonds by either constraining dihedral angles or manipulating charges. For the majority of simulations a consistent right handed twist is observed. The exceptions are two sets of simulations that block the O2-O6' intrachain hydrogen bond, where no consistent twist is observed in multiple independent simulations suggesting that the O2-O6' hydrogen bond can drive twist. However, in a further simulation where exocyclic group rotation is also blocked, right-handed twist still develops suggesting that intrachain hydrogen bonds are not necessary to drive twist in cellulose microfibrils.
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Affiliation(s)
- Sridhar Kumar Kannam
- Faculty of Science, Engineering and Technology, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Daniel P Oehme
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Monika S Doblin
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michael J Gidley
- ARC Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Antony Bacic
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Matthew T Downton
- IBM Research Australia, Level 5, 204 Lygon Street, 3053 Carlton, Victoria, Australia.
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73
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Penttilä PA, Imai T, Sugiyama J. Fibrillar assembly of bacterial cellulose in the presence of wood-based hemicelluloses. Int J Biol Macromol 2017; 102:111-118. [PMID: 28392383 DOI: 10.1016/j.ijbiomac.2017.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 03/31/2017] [Accepted: 04/03/2017] [Indexed: 01/19/2023]
Abstract
Composite materials mimicking the plant cell wall structure were made by culturing cellulose-producing bacteria together with secondary-wall hemicelluloses from wood. The effects of spruce galactoglucomannan (GGM) and beech xylan on the nanoscale morphology of bacterial cellulose were studied in the original, hydrated state with small-angle X-ray scattering (SAXS). The SAXS intensities were fitted with a model covering multiple levels of the hierarchical structure. Additional information on the structure of dried samples was obtained using scanning and transmission electron microscopy and infra-red spectroscopy. Both hemicelluloses induced a partial conversion of the cellulose crystal structure from Iα to Iβ and a reduction of the cross-sectional dimensions of the cellulose microfibrils, thereby affecting also their packing into bundles. The differences were more pronounced in samples with xylan instead of GGM, and they became more significant with higher hemicellulose concentrations.
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Affiliation(s)
- Paavo A Penttilä
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Tomoya Imai
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Junji Sugiyama
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji 611-0011, Japan
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74
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Frka-Petesic B, Radavidson H, Jean B, Heux L. Dynamically Controlled Iridescence of Cholesteric Cellulose Nanocrystal Suspensions Using Electric Fields. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1606208. [PMID: 28112444 DOI: 10.1002/adma.201606208] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 12/12/2016] [Indexed: 05/20/2023]
Abstract
Cellulose nanocrystal suspensions in apolar solvent spontaneously form iridescent liquid-crystalline phases but the control of their macroscopic order is usually poor. The use of electric fields can provide control on the cholesteric orientation and its periodicity, allowing macroscopic sample homogeneity and dynamical tuning of their iridescent hues, and is demonstrated here.
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Affiliation(s)
- Bruno Frka-Petesic
- Centre de Recherche sur les Macromolécules Végétales (CERMAV-CNRS), Université Grenoble Alpes, F-38000, Grenoble, France
| | - Harisoa Radavidson
- Centre de Recherche sur les Macromolécules Végétales (CERMAV-CNRS), Université Grenoble Alpes, F-38000, Grenoble, France
| | - Bruno Jean
- Centre de Recherche sur les Macromolécules Végétales (CERMAV-CNRS), Université Grenoble Alpes, F-38000, Grenoble, France
| | - Laurent Heux
- Centre de Recherche sur les Macromolécules Végétales (CERMAV-CNRS), Université Grenoble Alpes, F-38000, Grenoble, France
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75
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Murillo JD, Biernacki JJ, Northrup S, Mohammad AS. BIOMASS PYROLYSIS KINETICS: A REVIEW OF MOLECULAR-SCALE MODELING CONTRIBUTIONS. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2017. [DOI: 10.1590/0104-6632.20170341s20160086] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- J. D. Murillo
- Tennessee Technological University, USA; Tennessee Technological University, USA
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76
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Lindh EL, Terenzi C, Salmén L, Furó I. Water in cellulose: evidence and identification of immobile and mobile adsorbed phases by 2H MAS NMR. Phys Chem Chem Phys 2017; 19:4360-4369. [DOI: 10.1039/c6cp08219j] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The organization of water molecules adsorbed onto cellulose and the supramolecular hydrated structure of microfibril aggregates represents, still today, one of the open and complex questions in the physical chemistry of natural polymers.
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Affiliation(s)
- E. L. Lindh
- Division of Applied Physical Chemistry
- Department of Chemistry
- KTH Royal Institute of Technology
- SE-10044 Stockholm
- Sweden
| | - C. Terenzi
- Division of Applied Physical Chemistry
- Department of Chemistry
- KTH Royal Institute of Technology
- SE-10044 Stockholm
- Sweden
| | - L. Salmén
- Wallenberg Wood Science Center
- KTH Royal Institute of Technology
- SE-10044 Stockholm
- Sweden
- Innventia AB
| | - I. Furó
- Division of Applied Physical Chemistry
- Department of Chemistry
- KTH Royal Institute of Technology
- SE-10044 Stockholm
- Sweden
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77
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Lindh EL, Bergenstråhle-Wohlert M, Terenzi C, Salmén L, Furó I. Non-exchanging hydroxyl groups on the surface of cellulose fibrils: The role of interaction with water. Carbohydr Res 2016; 434:136-142. [DOI: 10.1016/j.carres.2016.09.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 10/21/2022]
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78
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Martínez-Sanz M, Mikkelsen D, Flanagan BM, Rehm C, de Campo L, Gidley MJ, Gilbert EP. Investigation of the micro- and nano-scale architecture of cellulose hydrogels with plant cell wall polysaccharides: A combined USANS/SANS study. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.07.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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79
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Zhu MZ, Chen YF, Zhu WB, Du XM, Zhou JB, Gu C, Liao RJ. Mechanical property of hydrous amorphous cellulose studied by molecular dynamics. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2016. [DOI: 10.1134/s199079311603012x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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80
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Majoinen J, Hassinen J, Haataja JS, Rekola HT, Kontturi E, Kostiainen MA, Ras RHA, Törmä P, Ikkala O. Chiral Plasmonics Using Twisting along Cellulose Nanocrystals as a Template for Gold Nanoparticles. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:5262-7. [PMID: 27152434 DOI: 10.1002/adma.201600940] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Indexed: 05/27/2023]
Abstract
The right-handed twist along aqueous dispersed cellulose nanocrystals allows right-handed chiral plasmonics upon electrostatic binding of gold nanoparticles in dilute environment, through tuning the particle sizes and concentrations. Simulations using nanoparticle coordinates from cryo-electron tomography confirm the experimental results. The finding suggests generalization for other chiral and helical colloidal templates for nanoscale chiral plasmonics.
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Affiliation(s)
- Johanna Majoinen
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
| | - Jukka Hassinen
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
| | - Johannes S Haataja
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
| | - Heikki T Rekola
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
| | - Eero Kontturi
- Department of Forest Products Technology, Aalto University, P. O. Box 16300, FIN-00076, Aalto, Espoo, Finland
| | - Mauri A Kostiainen
- Department of Biotechnology and Chemical Technology, Aalto University, P. O. Box 16100, FIN-00076, Aalto, Espoo, Finland
| | - Robin H A Ras
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
| | - Päivi Törmä
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
| | - Olli Ikkala
- Department of Applied Physics, Aalto University, P. O. Box 15100, FIN-00076, Aalto, Espoo, Finland
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81
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Hadden JA, French AD, Woods RJ. Unraveling cellulose microfibrils: a twisted tale. Biopolymers 2016; 99:746-56. [PMID: 23681971 DOI: 10.1002/bip.22279] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 05/03/2013] [Indexed: 12/26/2022]
Abstract
Molecular dynamics (MD) simulations of cellulose microfibrils are pertinent to the paper, textile, and biofuels industries for their unique capacity to characterize dynamic behavior and atomic-level interactions with solvent molecules and cellulase enzymes. While high-resolution crystallographic data have established a solid basis for computational analysis of cellulose, previous work has demonstrated a tendency for modeled microfibrils to diverge from the linear experimental structure and adopt a twisted conformation. Here, we investigate the dependence of this twisting behavior on computational approximations and establish the theoretical basis for its occurrence. We examine the role of solvent, the effect of nonbonded force field parameters [partial charges and van der Waals (vdW) contributions], and the use of explicitly modeled oxygen lone pairs in both the solute and solvent. Findings suggest that microfibril twisting is favored by vdW interactions, and counteracted by both intrachain hydrogen bonds and solvent effects at the microfibril surface.
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Affiliation(s)
- Jodi A Hadden
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602
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82
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Lay WK, Miller MS, Elcock AH. Optimizing Solute-Solute Interactions in the GLYCAM06 and CHARMM36 Carbohydrate Force Fields Using Osmotic Pressure Measurements. J Chem Theory Comput 2016; 12:1401-7. [PMID: 26967542 DOI: 10.1021/acs.jctc.5b01136] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
GLYCAM06 and CHARMM36 are successful force fields for modeling carbohydrates. To correct recently identified deficiencies with both force fields, we adjusted intersolute nonbonded parameters to reproduce the experimental osmotic coefficient of glucose at 1 M. The modified parameters improve behavior of glucose and sucrose up to 4 M and improve modeling of a dextran 55-mer. While the modified parameters may not be applicable to all carbohydrates, they highlight the use of osmotic simulations to optimize force fields.
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Affiliation(s)
- Wesley K Lay
- Department of Biochemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Mark S Miller
- Department of Biochemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Adrian H Elcock
- Department of Biochemistry, University of Iowa , Iowa City, Iowa 52242, United States
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83
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Miyamoto H, Schnupf U, Crowley MF, Brady JW. Comparison of the simulations of cellulosic crystals with three carbohydrate force fields. Carbohydr Res 2016; 422:17-23. [DOI: 10.1016/j.carres.2016.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/31/2015] [Accepted: 01/04/2016] [Indexed: 01/12/2023]
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84
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Martínez-Sanz M, Gidley MJ, Gilbert EP. Hierarchical architecture of bacterial cellulose and composite plant cell wall polysaccharide hydrogels using small angle neutron scattering. SOFT MATTER 2016; 12:1534-49. [PMID: 26658920 DOI: 10.1039/c5sm02085a] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Small angle neutron scattering (SANS) has been applied to characterise the structure of pure bacterial cellulose hydrogels, and composites thereof, with two plant cell wall polysaccharides (arabinoxylan and xyloglucan). Conventional published models, which assume that bacterial cellulose ribbons are solid one-phase systems, fail to adequately describe the SANS data of pure bacterial cellulose. Fitting of the neutron scattering profiles instead suggests that the sub-structure of cellulose microfibrils contained within the ribbons results in the creation of regions with distinct values of neutron scattering length density, when the hydrogels are subjected to H2O/D2O exchange. This may be represented within a core-shell formalism that considers the cellulose ribbons to comprise a core containing impermeable crystallites surrounded by a network of paracrystalline cellulose and tightly bound water, and a shell containing only paracrystalline cellulose and water. Accordingly, a fitting function comprising the sum of a power-law term to account for the large scale structure of intertwined ribbons, plus a core-shell cylinder with polydisperse radius, has been applied; it is demonstrated to simultaneously describe all SANS contrast variation data of pure and composite bacterial cellulose hydrogels. In addition, the resultant fitting parameters indicate distinct interaction mechanisms of arabinoxylan and xyloglucan with cellulose, revealing the potential of this approach to investigate the role of different plant cell wall polysaccharides on the biosynthesis process of cellulose.
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Affiliation(s)
- Marta Martínez-Sanz
- Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia.
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85
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Lukasheva NV, Tolmachev DA. Cellulose Nanofibrils and Mechanism of their Mineralization in Biomimetic Synthesis of Hydroxyapatite/Native Bacterial Cellulose Nanocomposites: Molecular Dynamics Simulations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:125-134. [PMID: 26652774 DOI: 10.1021/acs.langmuir.5b03953] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Molecular dynamics (MD) simulation of a nanofibril of native bacterial cellulose (BC) in solutions of mineral ions is presented. The supersaturated calcium-phosphate (CP) solution with the ionic composition of hydroxyapatite and CaCl2 solutions with the concentrations below, equal to, and above the solubility limits are simulated. The influence of solvation models (TIP3P and TIP4P-ew water models) on structural characteristics of the simulated nanofibril and on the crystal nucleation process is assessed. The structural characteristics of cellulose nanofibrils (in particular, of the surface layer) are found to be nearly independent of the solvation models used in the simulation and on the presence of ions in the solutions. It is shown that ionic clusters are formed in the solution rather than on the fibril surface. The cluster sizes are slightly different for the two water models. The effect of the ion-ion interaction parameters on the results is discussed. The main conclusion is that the activity of hydroxyl groups on the BC fibril surface is not high enough to cause adsorption of Ca(2+) ions from the solution. Therefore, the nucleation of CP crystals takes place initially in solution, and then the crystallites formed can be adsorbed on BC nanofibril surfaces.
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Affiliation(s)
- N V Lukasheva
- Institute of Macromolecular Compounds, Russian Academy of Sciences , Bol'shoi pr. 31, St. Petersburg, 199004 Russia
| | - D A Tolmachev
- Institute of Macromolecular Compounds, Russian Academy of Sciences , Bol'shoi pr. 31, St. Petersburg, 199004 Russia
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86
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Khazanov N, Iline-Vul T, Noy E, Goobes G, Senderowitz H. Design of Compact Biomimetic Cellulose Binding Peptides as Carriers for Cellulose Catalytic Degradation. J Phys Chem B 2016; 120:309-19. [DOI: 10.1021/acs.jpcb.5b11050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Netaly Khazanov
- Department of Chemistry, Bar Ilan University, Ramat Gan 5290002, Israel
| | - Taly Iline-Vul
- Department of Chemistry, Bar Ilan University, Ramat Gan 5290002, Israel
| | - Efrat Noy
- Department of Chemistry, Bar Ilan University, Ramat Gan 5290002, Israel
| | - Gil Goobes
- Department of Chemistry, Bar Ilan University, Ramat Gan 5290002, Israel
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87
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Mathew AK, Parameshwaran B, Sukumaran RK, Pandey A. An evaluation of dilute acid and ammonia fiber explosion pretreatment for cellulosic ethanol production. BIORESOURCE TECHNOLOGY 2016; 199:13-20. [PMID: 26358144 DOI: 10.1016/j.biortech.2015.08.121] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 08/24/2015] [Accepted: 08/27/2015] [Indexed: 06/05/2023]
Abstract
The challenge associated with cellulosic ethanol production is maximizing sugar yield at low cost. Current research is being focused to develop a pretreatment method to overcome biomass recalcitrance in an efficient way. This review is focused on two major pretreatments: dilute acid (DA) and ammonia fiber explosion (AFEX) pretreatment of corn stover and how these pretreatment cause morphological and chemical changes to corn stover in order to overcome the biomass recalcitrance. This review highlights the key differences of these two pretreatments based on compositional analysis, cellulose and its crystallinity, morphological changes, structural changes to lignin, enzymatic reactivity and enzyme adsorption onto pretreated solids and finally cellulosic ethanol production from the hydrolysate of DA and AFEX treated corn stover. Each stage of the process, AFEX pretreated corn stover was superior to DA treated corn stover.
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Affiliation(s)
- Anil Kuruvilla Mathew
- Centre for Biofuels, Biotechnology Division, National Institute for Interdisciplinary Science and Technology (CSIR), Trivandrum 695019, India
| | - Binod Parameshwaran
- Centre for Biofuels, Biotechnology Division, National Institute for Interdisciplinary Science and Technology (CSIR), Trivandrum 695019, India
| | - Rajeev Kumar Sukumaran
- Centre for Biofuels, Biotechnology Division, National Institute for Interdisciplinary Science and Technology (CSIR), Trivandrum 695019, India
| | - Ashok Pandey
- Centre for Biofuels, Biotechnology Division, National Institute for Interdisciplinary Science and Technology (CSIR), Trivandrum 695019, India
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88
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Conley K, Godbout L, Whitehead M(T, van de Ven TG. Origin of the twist of cellulosic materials. Carbohydr Polym 2016; 135:285-99. [DOI: 10.1016/j.carbpol.2015.08.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 08/03/2015] [Accepted: 08/10/2015] [Indexed: 10/23/2022]
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89
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Pretreatment Processes for Cellulosic Ethanol Production: Processes Integration and Modeling for the Utilization of Lignocellulosics Such as Sugarcane Straw. GREEN FUELS TECHNOLOGY 2016. [DOI: 10.1007/978-3-319-30205-8_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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90
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Wang T, Hong M. Solid-state NMR investigations of cellulose structure and interactions with matrix polysaccharides in plant primary cell walls. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:503-14. [PMID: 26355148 PMCID: PMC6280985 DOI: 10.1093/jxb/erv416] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Until recently, the 3D architecture of plant cell walls was poorly understood due to the lack of high-resolution techniques for characterizing the molecular structure, dynamics, and intermolecular interactions of the wall polysaccharides in these insoluble biomolecular mixtures. We introduced multidimensional solid-state NMR (SSNMR) spectroscopy, coupled with (13)C labelling of whole plants, to determine the spatial arrangements of macromolecules in near-native plant cell walls. Here we review key evidence from 2D and 3D correlation NMR spectra that show relatively few cellulose-hemicellulose cross peaks but many cellulose-pectin cross peaks, indicating that cellulose microfibrils are not extensively coated by hemicellulose and all three major polysaccharides exist in a single network rather than two separate networks as previously proposed. The number of glucan chains in the primary-wall cellulose microfibrils has been under active debate recently. We show detailed analysis of quantitative (13)C SSNMR spectra of cellulose in various wild-type (WT) and mutant Arabidopsis and Brachypodium primary cell walls, which consistently indicate that primary-wall cellulose microfibrils contain at least 24 glucan chains.
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Affiliation(s)
- Tuo Wang
- Department of Chemistry, Massachusetts Institute of Technology, 170 Albany Street, Cambridge, MA 02139, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, 170 Albany Street, Cambridge, MA 02139, USA
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91
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Schulz R, Lindner B, Petridis L, Smith JC. Scaling of Multimillion-Atom Biological Molecular Dynamics Simulation on a Petascale Supercomputer. J Chem Theory Comput 2015; 5:2798-808. [PMID: 26631792 DOI: 10.1021/ct900292r] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A strategy is described for a fast all-atom molecular dynamics simulation of multimillion-atom biological systems on massively parallel supercomputers. The strategy is developed using benchmark systems of particular interest to bioenergy research, comprising models of cellulose and lignocellulosic biomass in an aqueous solution. The approach involves using the reaction field (RF) method for the computation of long-range electrostatic interactions, which permits efficient scaling on many thousands of cores. Although the range of applicability of the RF method for biomolecular systems remains to be demonstrated, for the benchmark systems the use of the RF produces molecular dipole moments, Kirkwood G factors, other structural properties, and mean-square fluctuations in excellent agreement with those obtained with the commonly used Particle Mesh Ewald method. With RF, three million- and five million-atom biological systems scale well up to ∼30k cores, producing ∼30 ns/day. Atomistic simulations of very large systems for time scales approaching the microsecond would, therefore, appear now to be within reach.
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Affiliation(s)
- Roland Schulz
- Center for Molecular Biophysics, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, M407 Walters Life Sciences 1414 Cumberland Avenue, Knoxville, Tennessee 37996, and BioEnergy Science Center, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831
| | - Benjamin Lindner
- Center for Molecular Biophysics, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, M407 Walters Life Sciences 1414 Cumberland Avenue, Knoxville, Tennessee 37996, and BioEnergy Science Center, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831
| | - Loukas Petridis
- Center for Molecular Biophysics, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, M407 Walters Life Sciences 1414 Cumberland Avenue, Knoxville, Tennessee 37996, and BioEnergy Science Center, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831
| | - Jeremy C Smith
- Center for Molecular Biophysics, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, M407 Walters Life Sciences 1414 Cumberland Avenue, Knoxville, Tennessee 37996, and BioEnergy Science Center, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831
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92
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Vuoriluoto M, Orelma H, Johansson LS, Zhu B, Poutanen M, Walther A, Laine J, Rojas OJ. Effect of Molecular Architecture of PDMAEMA–POEGMA Random and Block Copolymers on Their Adsorption on Regenerated and Anionic Nanocelluloses and Evidence of Interfacial Water Expulsion. J Phys Chem B 2015; 119:15275-86. [DOI: 10.1021/acs.jpcb.5b07628] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Maija Vuoriluoto
- Biobased
Colloids and Materials group (BiCMat), Department of Forest Products
Technology, School of Chemical Technology, Aalto University, FI-00076, Espoo, Finland
| | - Hannes Orelma
- Biobased
Colloids and Materials group (BiCMat), Department of Forest Products
Technology, School of Chemical Technology, Aalto University, FI-00076, Espoo, Finland
- VTT, Technical Research Centre of Finland, Biologinkuja 7, P.O. Box 1000, FIN-02044 VTT, Finland
| | - Leena-Sisko Johansson
- Biobased
Colloids and Materials group (BiCMat), Department of Forest Products
Technology, School of Chemical Technology, Aalto University, FI-00076, Espoo, Finland
| | - Baolei Zhu
- DWI − Leibniz-Institute for Interactive Materials Research, Forckenbeckstr. 50, D-52056 Aachen, Germany
| | - Mikko Poutanen
- Department
of Applied Physics, School of Science, Aalto University, FI-00076, Espoo, Finland
| | - Andreas Walther
- DWI − Leibniz-Institute for Interactive Materials Research, Forckenbeckstr. 50, D-52056 Aachen, Germany
| | - Janne Laine
- Biobased
Colloids and Materials group (BiCMat), Department of Forest Products
Technology, School of Chemical Technology, Aalto University, FI-00076, Espoo, Finland
| | - Orlando J. Rojas
- Biobased
Colloids and Materials group (BiCMat), Department of Forest Products
Technology, School of Chemical Technology, Aalto University, FI-00076, Espoo, Finland
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93
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Meng C, Lu H, Cao GP, Yao CW, Liu Y, Zhang QM, Bai YB, Wang H. Activation of Cellulose by Supercritical Tetrafluoroethane and Its Application in Synthesis of Cellulose Acetate. Ind Eng Chem Res 2015. [DOI: 10.1021/acs.iecr.5b03418] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Chen Meng
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Hui Lu
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Gui-Ping Cao
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Chen-Wei Yao
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yue Liu
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Qi-Ming Zhang
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yun-Bo Bai
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Hua Wang
- UNILAB,
State Key Lab of
Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
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94
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Babaee M, Jonoobi M, Hamzeh Y, Ashori A. Biodegradability and mechanical properties of reinforced starch nanocomposites using cellulose nanofibers. Carbohydr Polym 2015; 132:1-8. [DOI: 10.1016/j.carbpol.2015.06.043] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 06/10/2015] [Accepted: 06/12/2015] [Indexed: 11/16/2022]
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95
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Kulasinski K, Guyer R, Derome D, Carmeliet J. Water Adsorption in Wood Microfibril-Hemicellulose System: Role of the Crystalline–Amorphous Interface. Biomacromolecules 2015; 16:2972-8. [DOI: 10.1021/acs.biomac.5b00878] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Karol Kulasinski
- Chair
of Building Physics, Swiss Federal University of Technology Zurich, Stefano-Franscini-Platz 5, 8093 Zürich, Switzerland
- Laboratory
for Multiscale Studies in Building Physics, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Robert Guyer
- Solid
Earth Geophysics Group, Los Alamos National Laboratory, MS D446, Los Alamos, New Mexico 87545, United States
- Department
of Physics, University of Nevada, 1664 North Virginia Street, Reno, Nevada 89557, United States
| | - Dominique Derome
- Laboratory
for Multiscale Studies in Building Physics, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Jan Carmeliet
- Chair
of Building Physics, Swiss Federal University of Technology Zurich, Stefano-Franscini-Platz 5, 8093 Zürich, Switzerland
- Laboratory
for Multiscale Studies in Building Physics, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
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96
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Poma AB, Chwastyk M, Cieplak M. Polysaccharide-Protein Complexes in a Coarse-Grained Model. J Phys Chem B 2015; 119:12028-41. [PMID: 26291477 DOI: 10.1021/acs.jpcb.5b06141] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We construct two variants of coarse-grained models of three hexaoses: one based on the centers of mass of the monomers and the other associated with the C4 atoms. The latter is found to be better defined and more suitable for studying interactions with proteins described within α-C based models. We determine the corresponding effective stiffness constants through all-atom simulations and two statistical methods. One method is the Boltzmann inversion (BI) and the other, named energy-based (EB), involves direct monitoring of energies as a function of the variables that define the stiffness potentials. The two methods are generally consistent in their account of the stiffness. We find that the elastic constants differ between the hexaoses and are noticeably different from those determined for the crystalline cellulose Iβ. The nonbonded couplings through hydrogen bonds between different sugar molecules are modeled by the Lennard-Jones potentials and are found to be stronger than the hydrogen bonds in proteins. We observe that the EB method agrees with other theoretical and experimental determinations of the nonbonded parameters much better than BI. We then consider the hexaose-Man5B catalytic complexes and determine the contact energies between their the C4-α-C atoms. These interactions are found to be stronger than the proteinic hydrogen bonds: about four times as strong for cellohexaose and two times for mannohexaose. The fluctuational dynamics of the coarse-grained complexes are found to be compatible with previous all-atom studies by Bernardi et al.
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Affiliation(s)
- Adolfo B Poma
- Institute of Physics, Polish Academy of Sciences , Aleja Lotników 32/46, 02-668 Warsaw, Poland
| | - Mateusz Chwastyk
- Institute of Physics, Polish Academy of Sciences , Aleja Lotników 32/46, 02-668 Warsaw, Poland
| | - Marek Cieplak
- Institute of Physics, Polish Academy of Sciences , Aleja Lotników 32/46, 02-668 Warsaw, Poland
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97
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Bu L, Himmel ME, Crowley MF. The molecular origins of twist in cellulose I-beta. Carbohydr Polym 2015; 125:146-52. [DOI: 10.1016/j.carbpol.2015.02.023] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 02/01/2015] [Accepted: 02/12/2015] [Indexed: 10/24/2022]
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98
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Lyubimova O, Stoyanov SR, Gusarov S, Kovalenko A. Electric Interfacial Layer of Modified Cellulose Nanocrystals in Aqueous Electrolyte Solution: Predictions by the Molecular Theory of Solvation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:7106-7116. [PMID: 26053228 DOI: 10.1021/acs.langmuir.5b00680] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The X-ray crystal structure-based models of Iα cellulose nanocrystals (CNC), both pristine and containing surface sulfate groups with negative charge 0-0.34 e/nm(2) produced by sulfuric acid hydrolysis of softwood pulp, feature a highly polarized "crystal-like" charge distribution. We perform sampling using molecular dynamics (MD) of the structural relaxation of neutral pristine and negatively charged sulfated CNC of various lengths in explicit water solvent and then employ the statistical mechanical 3D-RISM-KH molecular theory of solvation to evaluate the solvation structure and thermodynamics of the relaxed CNC in ambient aqueous NaCl solution at a concentration of 0.0-0.25 mol/kg. The MD sampling induces a right-hand twist in CNC and rearranges its initially ordered structure with a macrodipole of high-density charges at the opposite faces into small local spots of alternating charge at each face. This surface charge rearrangement observed for both neutral and charged CNC significantly affects the distribution of ions around CNC in aqueous electrolyte solution. The solvation free energy (SFE) of charged sulfated CNC has a minimum at a particular electrolyte concentration depending on the surface charge density, whereas the SFE of neutral CNC increases linearly with NaCl concentration. The SFE contribution from Na(+) counterions exhibits behavior similar to the NaCl concentration dependence of the whole SFE. An analysis of the 3D maps of Na(+) density distributions shows that these model CNC particles exhibit the behavior of charged nanocolloids in aqueous electrolyte solution: an increase in electrolyte concentration shrinks the electric interfacial layer and weakens the effective repulsion between charged CNC particles. The 3D-RISM-KH method readily treats solvent and electrolyte of a given nature and concentration to predict effective interactions between CNC particles in electrolyte solution. We provide CNC structural models and a modeling procedure for studies of effective interactions and the formation of ordered phases of CNC suspensions in electrolyte solution.
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Affiliation(s)
- Olga Lyubimova
- †National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
- ‡Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta T6G 2G8, Canada
| | - Stanislav R Stoyanov
- †National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
- ‡Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta T6G 2G8, Canada
- §Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada
| | - Sergey Gusarov
- †National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Andriy Kovalenko
- †National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
- ‡Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta T6G 2G8, Canada
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99
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Understanding nanocellulose chirality and structure-properties relationship at the single fibril level. Nat Commun 2015; 6:7564. [PMID: 26108282 PMCID: PMC4491835 DOI: 10.1038/ncomms8564] [Citation(s) in RCA: 228] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 05/19/2015] [Indexed: 12/12/2022] Open
Abstract
Nanocellulose fibrils are ubiquitous in nature and nanotechnologies but their mesoscopic structural assembly is not yet fully understood. Here we study the structural features of rod-like cellulose nanoparticles on a single particle level, by applying statistical polymer physics concepts on electron and atomic force microscopy images, and we assess their physical properties via quantitative nanomechanical mapping. We show evidence of right-handed chirality, observed on both bundles and on single fibrils. Statistical analysis of contours from microscopy images shows a non-Gaussian kink angle distribution. This is inconsistent with a structure consisting of alternating amorphous and crystalline domains along the contour and supports process-induced kink formation. The intrinsic mechanical properties of nanocellulose are extracted from nanoindentation and persistence length method for transversal and longitudinal directions, respectively. The structural analysis is pushed to the level of single cellulose polymer chains, and their smallest associated unit with a proposed 2 × 2 chain-packing arrangement. Cellulose is a material found in many different biological systems, but the fine structure at the single-molecule level is still being assessed. Here, the authors present high-resolution imaging of cellulose structures at the single particle level, finding evidence of chirality in bundles and fibrils.
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100
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Alqus R, Eichhorn SJ, Bryce RA. Molecular Dynamics of Cellulose Amphiphilicity at the Graphene–Water Interface. Biomacromolecules 2015; 16:1771-83. [DOI: 10.1021/acs.biomac.5b00307] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rasha Alqus
- Manchester
Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Stephen J. Eichhorn
- Centre
for Graphene Science, College of Engineering, Maths and Physical Sciences, University of Exeter, Physics Building, Stocker Road, Exeter, Devon, EX4 4QL, United Kingdom
| | - Richard A. Bryce
- Manchester
Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
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