The role of plant cell wall encapsulation and porosity in regulating lipolysis during the digestion of almond seeds

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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Microbial Endoxylanases: Effective Weapons to Breach the Plant Cell-Wall Barrier or, Rather, Triggers of Plant Defense Systems?

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-19-1072 ◽

2006 ◽

Vol 19 (10) ◽

pp. 1072-1081 ◽

Cited By ~ 80

Author(s):

Tim Beliën ◽

Steven Van Campenhout ◽

Johan Robben ◽

Guido Volckaert

Keyword(s):

Cell Wall ◽

Plant Defense ◽

Plant Cell ◽

Cell Walls ◽

Defense Mechanisms ◽

Plant Cell Wall ◽

Cell Wall Degrading Enzymes ◽

Defense Systems ◽

Xylanase Inhibitor

Endo-β-1,4-xylanases (EC 3.2.1.8) are key enzymes in the degradation of xylan, the predominant hemicellulose in the cell walls of plants and the second most abundant polysaccharide on earth. A number of endoxylanases are produced by microbial phytopathogens responsible for severe crop losses. These enzymes are considered to play an important role in phytopathogenesis, as they provide essential means to the attacking organism to break through the plant cell wall. Plants have evolved numerous defense mechanisms to protect themselves against invading pathogens, amongst which are proteinaceous inhibitors of cell wall-degrading enzymes. These defense mechanisms are triggered when a pathogen-derived elicitor is recognized by the plant. In this review, the diverse aspects of endoxylanases in promoting virulence and in eliciting plant defense systems are highlighted. Furthermore, the role of the relatively recently discovered cereal endoxylanase inhibitor families TAXI (Triticum aestivum xylanase inhibitor) and XIP (xylanase inhibitor protein) in plant defense is discussed.

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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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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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Role of cytoskeleton in plant cell wall formation

Scientia Sinica Vitae ◽

10.1360/ssv-2019-0168 ◽

2020 ◽

Vol 50 (2) ◽

pp. 176-186

Author(s):

Yi MAN ◽

RuiLi LI ◽

YuFen BU ◽

Na SUN ◽

YanPing JING ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Plant Cell Wall ◽

Cell Wall Formation ◽

Wall Formation

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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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Sheep Digestive Physiology and Constituents of Feeds

Sheep Farming - An Approach to Feed, Growth and Health ◽

10.5772/intechopen.92054 ◽

2021 ◽

Author(s):

Samir Medjekal ◽

Mouloud Ghadbane

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Plant Cell Wall ◽

Early Stage ◽

Growth Period ◽

Cell Plate ◽

Soluble Carbohydrates ◽

Winter Period ◽

The Common

Sheep have a gastrointestinal tract similar to that of other ruminants. Their stomach is made up of four digestive organs: the rumen, the reticulum, the omasum and the abomasum. The rumen plays a role in storing ingested foods, which are fermented by a complex anaerobic rumen microbiota population with different types of interactions, positive or negative, that can occur between their microbial populations. Sheep feeding is largely based on the use of natural or cultivated fodder, which is exploited in green by grazing during the growth period of the grass and in the form of fodder preserved during the winter period. Ruminant foods are essentially of plant origin, and their constituents belong to two types of structures: intracellular constituents and cell wall components. Cellular carbohydrates play a role of metabolites or energy reserves; soluble carbohydrates account for less than 10% dry matter (DM) of foods. The plant cell wall is multi-layered and consists of primary wall and secondary wall. Fundamentally, the walls are deposited at an early stage of growth. A central blade forms the common boundary layer between two adjacent cells and occupies the location of the cell plate. Most of the plant cell walls consist of polysaccharides (cellulose, hemicellulose and pectic substances) and lignin, these constituents being highly polymerized, as well as proteins and tannins.

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Impact of plant cell wall network on biodegradation in soil: Role of lignin composition and phenolic acids in roots from 16 maize genotypes

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2011.04.002 ◽

2011 ◽

Vol 43 (7) ◽

pp. 1544-1552 ◽

Cited By ~ 47

Author(s):

Gaylord Erwan Machinet ◽

Isabelle Bertrand ◽

Yves Barrière ◽

Brigitte Chabbert ◽

Sylvie Recous

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Phenolic Acids ◽

Plant Cell Wall ◽

Maize Genotypes ◽

Lignin Composition ◽

Biodegradation In Soil

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Plant cell wall architecture: the role of pectins

Progress in Biotechnology - Pectins and Pectinases, Proceedings of an International Symposium ◽

10.1016/s0921-0423(96)80249-8 ◽

1996 ◽

pp. 91-107 ◽

Cited By ~ 11

Author(s):

M.C. McCann ◽

K. Roberts

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Plant Cell Wall ◽

Cell Wall Architecture

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The regulatory and transcriptional landscape associated with carbon utilization in a filamentous fungus

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1915611117 ◽

2020 ◽

Vol 117 (11) ◽

pp. 6003-6013 ◽

Cited By ~ 5

Author(s):

Vincent W. Wu ◽

Nils Thieme ◽

Lori B. Huberman ◽

Axel Dietschmann ◽

David J. Kowbel ◽

...

Keyword(s):

Cell Wall ◽

Transcription Factors ◽

Plant Cell ◽

Plant Cell Wall ◽

Plant Biomass ◽

Carbon Sources ◽

Cell Wall Degrading Enzymes ◽

Degrading Enzymes ◽

Genes Encoding

Filamentous fungi, such asNeurospora crassa, are very efficient in deconstructing plant biomass by the secretion of an arsenal of plant cell wall-degrading enzymes, by remodeling metabolism to accommodate production of secreted enzymes, and by enabling transport and intracellular utilization of plant biomass components. Although a number of enzymes and transcriptional regulators involved in plant biomass utilization have been identified, how filamentous fungi sense and integrate nutritional information encoded in the plant cell wall into a regulatory hierarchy for optimal utilization of complex carbon sources is not understood. Here, we performed transcriptional profiling ofN. crassaon 40 different carbon sources, including plant biomass, to provide data on how fungi sense simple to complex carbohydrates. From these data, we identified regulatory factors inN. crassaand characterized one (PDR-2) associated with pectin utilization and one with pectin/hemicellulose utilization (ARA-1). Using in vitro DNA affinity purification sequencing (DAP-seq), we identified direct targets of transcription factors involved in regulating genes encoding plant cell wall-degrading enzymes. In particular, our data clarified the role of the transcription factor VIB-1 in the regulation of genes encoding plant cell wall-degrading enzymes and nutrient scavenging and revealed a major role of the carbon catabolite repressor CRE-1 in regulating the expression of major facilitator transporter genes. These data contribute to a more complete understanding of cross talk between transcription factors and their target genes, which are involved in regulating nutrient sensing and plant biomass utilization on a global level.

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