Bundling of cellulose microfibrils in native and polyethylene glycol-containing wood cell walls revealed by small-angle neutron scattering

AbstractWood and other plant-based resources provide abundant, renewable raw materials for a variety of applications. Nevertheless, their utilization would greatly benefit from more efficient and accurate methods to characterize the detailed nanoscale architecture of plant cell walls. Non-invasive techniques such as neutron and X-ray scattering hold a promise for elucidating the hierarchical cell wall structure and any changes in its morphology, but their use is hindered by challenges in interpreting the experimental data. We used small-angle neutron scattering in combination with contrast variation by poly(ethylene glycol) (PEG) to identify the scattering contribution from cellulose microfibril bundles in native wood cell walls. Using this method, mean diameters for the microfibril bundles from 12 to 19 nm were determined, without the necessity of cutting, drying or freezing the cell wall. The packing distance of the individual microfibrils inside the bundles can be obtained from the same data. This finding opens up possibilities for further utilization of small-angle scattering in characterizing the plant cell wall nanostructure and its response to chemical, physical and biological modifications or even in situ treatments. Moreover, our results give new insights into the interaction between PEG and the wood nanostructure, which may be helpful for preservation of archaeological woods.

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Xylan decoration patterns and the plant secondary cell wall molecular architecture

Biochemical Society Transactions ◽

10.1042/bst20150183 ◽

2016 ◽

Vol 44 (1) ◽

pp. 74-78 ◽

Cited By ~ 35

Author(s):

Marta Busse-Wicher ◽

Nicholas J. Grantham ◽

Jan J. Lyczakowski ◽

Nino Nikolovski ◽

Paul Dupree

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Md Simulations ◽

Cellulose Microfibrils ◽

Molecular Architecture ◽

Cellulose Fibrils ◽

Main Component

The molecular architecture of plant secondary cell walls is still not resolved. There are several proposed structures for cellulose fibrils, the main component of plant cell walls and the conformation of other molecules is even less well known. Glucuronic acid (GlcA) substitution of xylan (GUX) enzymes, in CAZy family glycosyl transferase (GT)8, decorate the xylan backbone with various specific patterns of GlcA. It was recently discovered that dicot xylan has a domain with the side chain decorations distributed on every second unit of the backbone (xylose). If the xylan backbone folds in a similar way to glucan chains in cellulose (2-fold helix), this kind of arrangement may allow the undecorated side of the xylan chain to hydrogen bond with the hydrophilic surface of cellulose microfibrils. MD simulations suggest that such interactions are energetically stable. We discuss the possible role of this xylan decoration pattern in building of the plant cell wall.

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Finite Element Analysis of Plant Cell Wall Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.32.197 ◽

2008 ◽

Vol 32 ◽

pp. 197-202 ◽

Cited By ~ 1

Author(s):

Hung Kha ◽

Sigrid Tuble ◽

Shankar Kalyanasundaram ◽

Richard E. Williamson

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Wood Fiber ◽

Cellulose Microfibrils ◽

Element Analysis ◽

Young’S Moduli

Illuminating fundamental aspects of plant cell wall mechanics will lead to novel biological and engineering inspired strategies for application in the cotton and wood fiber industries and in developing novel plant-derived materials that are increasingly seen as environmentally friendly alternatives. The stiffness properties of cell wall polymers such as cellulose microfibrils and xyloglucans are known but the relationship between the composite structure of the wall and its effective stiffness remains poorly understood. Understanding this relationship is important to engineers using and designing plant-derived materials and to biologists studying plant growth. We have developed a software system to generate microfibril-xyloglucan networks resembling those found in cell walls. Finite element analysis was implemented to predict the effective Young’s modulus of varying sizes of the microfibril-xyloglucan network. Results from the finite element models show that the network’s effective moduli of the cell walls having microfibrils parallel to applied loadings are relatively high (~90-215MPa) compared with those of the walls having randomly oriented microfibrils (~20-47MPa). The walls having microfibrils parallel to each other but perpendicular to applied loadings have lowest stiffness (~17-118kPa). The Young’s moduli are significantly lower than those of its constituent polymers and generally in agreement with experimentally measured values.

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Discovery of putative Golgi S-Adenosyl methionine transporters reveals the importance of plant cell wall polysaccharide methylation

10.1101/2021.07.06.451061 ◽

2021 ◽

Author(s):

Henry Temple ◽

Pyae Phyo ◽

Weibing Yang ◽

Jan J Lyczakowski ◽

Alberto Echevarria-Poza ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Intact Cell ◽

Major Facilitator Superfamily ◽

Wall Structure ◽

Cell Wall Polysaccharide ◽

Knock Out ◽

Adenosyl Methionine

Polysaccharide methylation, especially that of pectin, is a common and important feature of land plant cell walls. Polysaccharide methylation takes place in the Golgi apparatus and therefore relies on the import of S-adenosyl methionine (SAM) from the cytosol into the Golgi. However, to date, no Golgi SAM transporter has been identified in plants. In this work, we studied major facilitator superfamily members in Arabidopsis that we identified as putative Golgi SAM transporters (GoSAMTs). Knock-out of the two most highly expressed GoSAMTs led to a strong reduction in Golgi-synthesised polysaccharide methylation. Furthermore, solid-state NMR experiments revealed that reduced methylation changed cell wall polysaccharide conformations, interactions and mobilities. Notably, the NMR revealed the existence of pectin egg-box structures in intact cell walls, and showed that their formation is enhanced by reduced methyl-esterification. These changes in wall architecture were linked to substantial growth and developmental phenotypes. In particular, anisotropic growth was strongly impaired in the double mutant. The identification of putative transporters that import SAM into the Golgi lumen in plants provides new insights into the paramount importance of polysaccharide methylation for plant cell wall structure and function.

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Recent findings in plant cell wall structure and metabolism: future challenges and potential implications for softening

Stewart Postharvest Review ◽

10.2212/spr.2006.2.9 ◽

2006 ◽

Vol 2 (2) ◽

pp. 1-8

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Plant Cell Wall ◽

Cell Wall Structure ◽

Wall Structure ◽

Future Challenges ◽

Structure And Metabolism

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Plant Cell Wall Hydration and Plant Physiology: An Exploration of the Consequences of Direct Effects of Water Deficit on the Plant Cell Wall

Plants ◽

10.3390/plants10071263 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1263

Author(s):

David Stuart Thompson ◽

Azharul Islam

Keyword(s):

Cell Wall ◽

Water Content ◽

Bacterial Cellulose ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Plant Cell Walls ◽

Cell Wall Polysaccharides ◽

Degree Of Hydration ◽

Cellulose Composites

The extensibility of synthetic polymers is routinely modulated by the addition of lower molecular weight spacing molecules known as plasticizers, and there is some evidence that water may have similar effects on plant cell walls. Furthermore, it appears that changes in wall hydration could affect wall behavior to a degree that seems likely to have physiological consequences at water potentials that many plants would experience under field conditions. Osmotica large enough to be excluded from plant cell walls and bacterial cellulose composites with other cell wall polysaccharides were used to alter their water content and to demonstrate that the relationship between water potential and degree of hydration of these materials is affected by their composition. Additionally, it was found that expansins facilitate rehydration of bacterial cellulose and cellulose composites and cause swelling of plant cell wall fragments in suspension and that these responses are also affected by polysaccharide composition. Given these observations, it seems probable that plant environmental responses include measures to regulate cell wall water content or mitigate the consequences of changes in wall hydration and that it may be possible to exploit such mechanisms to improve crop resilience.

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A Label-free, Fast and High-specificity Technique for Plant Cell Wall Imaging and Composition Analysis

10.21203/rs.3.rs-107437/v1 ◽

2020 ◽

Author(s):

Huimin Xu ◽

Yuanyuan Zhao ◽

Yuanzhen Suo ◽

Yayu Guo ◽

Yi Man ◽

...

Keyword(s):

Cell Wall ◽

Chemical Composition ◽

Raman Scattering ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Composition Analysis ◽

Plant Cell Walls ◽

Label Free ◽

Wall Imaging

Abstract Background: Cell wall imaging can considerably permit direct visualization of the molecular architecture of cell walls and provide the detailed chemical information on wall polymers, which is imperative to better exploit and use the biomass polymers; however, detailed imaging and quantifying of the native composition and architecture in the cell wall remains challenging.Results: Here, we describe a label-free imaging technology, coherent Raman scattering microscopy (CRS), including coherent anti-Stokes Raman scattering (CARS) microscopy and stimulated Raman scattering (SRS) microscopy, which images the major structures and chemical composition of plant cell walls. The major steps of the procedure are demonstrated, including sample preparation, setting the mapping parameters, analysis of spectral data, and image generation. Applying this rapid approach, which will help researchers understand the highly heterogeneous structures and organization of plant cell walls.Conclusions: This method can potentially be incorporated into label-free microanalyses of plant cell wall chemical composition based on the in situ vibrations of molecules.

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Plasmodesmata-Related Structural and Functional Proteins: The Long Sought-After Secrets of a Cytoplasmic Channel in Plant Cell Walls

International Journal of Molecular Sciences ◽

10.3390/ijms20122946 ◽

2019 ◽

Vol 20 (12) ◽

pp. 2946 ◽

Cited By ~ 7

Author(s):

Xiao Han ◽

Li-Jun Huang ◽

Dan Feng ◽

Wenhan Jiang ◽

Wenzhuo Miu ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plasma Membranes ◽

Plant Cell Wall ◽

Plant Cells ◽

Protein Composition ◽

Cell Contact ◽

Plant Cell Walls ◽

Cell Organelles

Plant cells are separated by cellulose cell walls that impede direct cell-to-cell contact. In order to facilitate intercellular communication, plant cells develop unique cell-wall-spanning structures termed plasmodesmata (PD). PD are membranous channels that link the cytoplasm, plasma membranes, and endoplasmic reticulum of adjacent cells to provide cytoplasmic and membrane continuity for molecular trafficking. PD play important roles for the development and physiology of all plants. The structure and function of PD in the plant cell walls are highly dynamic and tightly regulated. Despite their importance, plasmodesmata are among the few plant cell organelles that remain poorly understood. The molecular properties of PD seem largely elusive or speculative. In this review, we firstly describe the general PD structure and its protein composition. We then discuss the recent progress in identification and characterization of PD-associated plant cell-wall proteins that regulate PD function, with particular emphasis on callose metabolizing and binding proteins, and protein kinases targeted to and around PD.

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Feeding the Walls: How Does Nutrient Availability Regulate Cell Wall Composition?

International Journal of Molecular Sciences ◽

10.3390/ijms19092691 ◽

2018 ◽

Vol 19 (9) ◽

pp. 2691 ◽

Cited By ~ 11

Author(s):

Michael Ogden ◽

Rainer Hoefgen ◽

Ute Roessner ◽

Staffan Persson ◽

Ghazanfar Khan

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Nutrient Availability ◽

Cell Walls ◽

Plant Cell Wall ◽

Nutrient Status ◽

Cell Wall Composition ◽

Nutrient Sensing ◽

Tissue Type ◽

Wall Components

Nutrients are critical for plants to grow and develop, and nutrient depletion severely affects crop yield. In order to optimize nutrient acquisition, plants adapt their growth and root architecture. Changes in growth are determined by modifications in the cell walls surrounding every plant cell. The plant cell wall, which is largely composed of complex polysaccharides, is essential for plants to attain their shape and to protect cells against the environment. Within the cell wall, cellulose strands form microfibrils that act as a framework for other wall components, including hemicelluloses, pectins, proteins, and, in some cases, callose, lignin, and suberin. Cell wall composition varies, depending on cell and tissue type. It is governed by synthesis, deposition and remodeling of wall components, and determines the physical and structural properties of the cell wall. How nutrient status affects cell wall synthesis and organization, and thus plant growth and morphology, remains poorly understood. In this review, we aim to summarize and synthesize research on the adaptation of root cell walls in response to nutrient availability and the potential role of cell walls in nutrient sensing.

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The Spatio-Temporal Distribution of Cell Wall-Associated Glycoproteins During Wood Formation in Populus

Frontiers in Plant Science ◽

10.3389/fpls.2020.611607 ◽

2020 ◽

Vol 11 ◽

Author(s):

Tayebeh Abedi ◽

Romain Castilleux ◽

Pieter Nibbering ◽

Totte Niittylä

Keyword(s):

Gene Expression ◽

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Expression Patterns ◽

Wood Formation ◽

Cell Type Specificity ◽

Spatio Temporal ◽

Ray Cell

Plant cell wall associated hydroxyproline-rich glycoproteins (HRGPs) are involved in several aspects of plant growth and development, including wood formation in trees. HRGPs such as arabinogalactan-proteins (AGPs), extensins (EXTs), and proline rich proteins (PRPs) are important for the development and architecture of plant cell walls. Analysis of publicly available gene expression data revealed that many HRGP encoding genes show tight spatio-temporal expression patterns in the developing wood of Populus that are indicative of specific functions during wood formation. Similar results were obtained for the expression of glycosyl transferases putatively involved in HRGP glycosylation. In situ immunolabelling of transverse wood sections using AGP and EXT antibodies revealed the cell type specificity of different epitopes. In mature wood AGP epitopes were located in xylem ray cell walls, whereas EXT epitopes were specifically observed between neighboring xylem vessels, and on the ray cell side of the vessel walls, likely in association with pits. Molecular mass and glycan analysis of AGPs and EXTs in phloem/cambium, developing xylem, and mature xylem revealed clear differences in glycan structures and size between the tissues. Separation of AGPs by agarose gel electrophoresis and staining with β-D-glucosyl Yariv confirmed the presence of different AGP populations in phloem/cambium and xylem. These results reveal the diverse changes in HRGP-related processes that occur during wood formation at the gene expression and HRGP glycan biosynthesis levels, and relate HRGPs and glycosylation processes to the developmental processes of wood formation.

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