The Expression of a Bean PGIP in Transgenic Wheat Confers Increased Resistance to the Fungal Pathogen Bipolaris sorokiniana

A possible strategy to control plant pathogens is the improvement of natural plant defense mechanisms against the tools that pathogens commonly use to penetrate and colonize the host tissue. One of these mechanisms is represented by the host plant's ability to inhibit the pathogen's capacity to degrade plant cell wall polysaccharides. Polygalacturonase-inhibiting proteins (PGIP) are plant defense cell wall glycoproteins that inhibit the activity of fungal endopolygalacturonases (endo-PGs). To assess the effectiveness of these proteins in protecting wheat from fungal pathogens, we produced a number of transgenic wheat lines expressing a bean PGIP (PvPGIP2) having a wide spectrum of specificities against fungal PGs. Three independent transgenic lines were characterized in detail, including determination of the levels of PvPGIP2 accumulation and its subcellular localization and inhibitory activity. Results show that the transgene-encoded protein is correctly secreted into the apoplast, maintains its characteristic recognition specificities, and endows the transgenic wheat with new PG recognition capabilities. As a consequence, transgenic wheat tissue showed increased resistance to digestion by the PG of Fusarium moniliforme. These new properties also were confirmed at the plant level during interactions with the fungal pathogen Bipolaris sorokiniana. All three lines showed significant reductions in symptom progression (46 to 50%) through the leaves following infection with this pathogen. Our results illustrate the feasibility of improving wheat's defenses against pathogens by expression of proteins with new capabilities to counteract those produced by the pathogens.

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Structure and dynamics of Trichoderma harzianum Cel7B suggest molecular architecture adaptations required for a wide spectrum of activities on plant cell wall polysaccharides

Biochimica et Biophysica Acta (BBA) - General Subjects ◽

10.1016/j.bbagen.2019.03.013 ◽

2019 ◽

Vol 1863 (6) ◽

pp. 1015-1026 ◽

Cited By ~ 3

Author(s):

Milton T. Sonoda ◽

Andre S. Godoy ◽

Vanessa O.A. Pellegrini ◽

Marco A.S. Kadowaki ◽

Alessandro S. Nascimento ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Trichoderma Harzianum ◽

Plant Cell Wall ◽

Wide Spectrum ◽

Molecular Architecture ◽

Cell Wall Polysaccharides ◽

Structure And Dynamics

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Aspergillus Enzymes Involved in Degradation of Plant Cell Wall Polysaccharides

Microbiology and Molecular Biology Reviews ◽

10.1128/mmbr.65.4.497-522.2001 ◽

2001 ◽

Vol 65 (4) ◽

pp. 497-522 ◽

Cited By ~ 584

Author(s):

Ronald P. de Vries ◽

Jaap Visser

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Plant Cell Wall ◽

Current Knowledge ◽

Wide Spectrum ◽

Structural Characteristics ◽

Attractive Alternative ◽

Cell Wall Polysaccharide ◽

Cell Wall Polysaccharides ◽

Degrading Enzymes

SUMMARY Degradation of plant cell wall polysaccharides is of major importance in the food and feed, beverage, textile, and paper and pulp industries, as well as in several other industrial production processes. Enzymatic degradation of these polymers has received attention for many years and is becoming a more and more attractive alternative to chemical and mechanical processes. Over the past 15 years, much progress has been made in elucidating the structural characteristics of these polysaccharides and in characterizing the enzymes involved in their degradation and the genes of biotechnologically relevant microorganisms encoding these enzymes. The members of the fungal genus Aspergillus are commonly used for the production of polysaccharide-degrading enzymes. This genus produces a wide spectrum of cell wall-degrading enzymes, allowing not only complete degradation of the polysaccharides but also tailored modifications by using specific enzymes purified from these fungi. This review summarizes our current knowledge of the cell wall polysaccharide-degrading enzymes from aspergilli and the genes by which they are encoded.

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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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PUL-Mediated Plant Cell Wall Polysaccharide Utilization in the Gut Bacteroidetes

International Journal of Molecular Sciences ◽

10.3390/ijms22063077 ◽

2021 ◽

Vol 22 (6) ◽

pp. 3077

Author(s):

Zhenzhen Hao ◽

Xiaolu Wang ◽

Haomeng Yang ◽

Tao Tu ◽

Jie Zhang ◽

...

Keyword(s):

Cell Wall ◽

Microbial Community ◽

Gut Microbiota ◽

Plant Cell ◽

Plant Cell Wall ◽

Cell Wall Polysaccharide ◽

Prominent Feature ◽

Cell Wall Polysaccharides ◽

Gut Microbial Community

Plant cell wall polysaccharides (PCWP) are abundantly present in the food of humans and feed of livestock. Mammalians by themselves cannot degrade PCWP but rather depend on microbes resident in the gut intestine for deconstruction. The dominant Bacteroidetes in the gut microbial community are such bacteria with PCWP-degrading ability. The polysaccharide utilization systems (PUL) responsible for PCWP degradation and utilization are a prominent feature of Bacteroidetes. In recent years, there have been tremendous efforts in elucidating how PULs assist Bacteroidetes to assimilate carbon and acquire energy from PCWP. Here, we will review the PUL-mediated plant cell wall polysaccharides utilization in the gut Bacteroidetes focusing on cellulose, xylan, mannan, and pectin utilization and discuss how the mechanisms can be exploited to modulate the gut microbiota.

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Formation of Plant Cell Wall Polysaccharides

Nature ◽

10.1038/218878a0 ◽

1968 ◽

Vol 218 (5144) ◽

pp. 878-880 ◽

Cited By ~ 26

Author(s):

C. L. VILLEMEZ ◽

J. M. MCNAB ◽

P. ALBERSHEIM

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Plant Cell Wall ◽

Cell Wall Polysaccharides

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The Role of Arabinogalactan Type II Degradation in Plant-Microbe Interactions

Frontiers in Microbiology ◽

10.3389/fmicb.2021.730543 ◽

2021 ◽

Vol 12 ◽

Author(s):

Maria Guadalupe Villa-Rivera ◽

Horacio Cano-Camacho ◽

Everardo López-Romero ◽

María Guadalupe Zavala-Páramo

Keyword(s):

Cell Wall ◽

Plant Defense ◽

Plant Cell ◽

Plant Cell Wall ◽

Degradation Products ◽

Hydrolytic Enzymes ◽

Pathogenic Fungi ◽

Plant Interactions ◽

Root Tips ◽

Microbe Interactions

Arabinogalactans (AGs) are structural polysaccharides of the plant cell wall. A small proportion of the AGs are associated with hemicellulose and pectin. Furthermore, AGs are associated with proteins forming the so-called arabinogalactan proteins (AGPs), which can be found in the plant cell wall or attached through a glycosylphosphatidylinositol (GPI) anchor to the plasma membrane. AGPs are a family of highly glycosylated proteins grouped with cell wall proteins rich in hydroxyproline. These glycoproteins have important and diverse functions in plants, such as growth, cellular differentiation, signaling, and microbe-plant interactions, and several reports suggest that carbohydrate components are crucial for AGP functions. In beneficial plant-microbe interactions, AGPs attract symbiotic species of fungi or bacteria, promote the development of infectious structures and the colonization of root tips, and furthermore, these interactions can activate plant defense mechanisms. On the other hand, plants secrete and accumulate AGPs at infection sites, creating cross-links with pectin. As part of the plant cell wall degradation machinery, beneficial and pathogenic fungi and bacteria can produce the enzymes necessary for the complete depolymerization of AGs including endo-β-(1,3), β-(1,4) and β-(1,6)-galactanases, β-(1,3/1,6) galactanases, α-L-arabinofuranosidases, β-L-arabinopyranosidases, and β-D-glucuronidases. These hydrolytic enzymes are secreted during plant-pathogen interactions and could have implications for the function of AGPs. It has been proposed that AGPs could prevent infection by pathogenic microorganisms because their degradation products generated by hydrolytic enzymes of pathogens function as damage-associated molecular patterns (DAMPs) eliciting the plant defense response. In this review, we describe the structure and function of AGs and AGPs as components of the plant cell wall. Additionally, we describe the set of enzymes secreted by microorganisms to degrade AGs from AGPs and its possible implication for plant-microbe interactions.

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