Agricultural and Biological Sciences › Plant Science

Polysaccharides and Plant Cell Walls

Works Count: 42029

Wikipedia

Description

This cluster of papers explores the structure, biosynthesis, and functions of plant cell walls, focusing on components such as pectin, hemicelluloses, and cellulose synthesis. It also investigates the immunomodulatory and biomedical applications of plant polysaccharides, as well as the role of expansins in cell wall loosening.

Keywords

Pectin; Hemicelluloses; Cellulose Synthesis; Polysaccharides; Immune Recognition; Expansins; Molecular Structure; Enzymes; Biomedical Applications; Arabinogalactan Proteins

Pectin: cell biology and prospects for functional analysis

2001-01-01

William G. T. Willats , Lesley McCartney , William Mackie +1 more

Loosening of plant cell walls by expansins

2000-09-01

Daniel J. Cosgrove

Glycogen, hyaluronate, and some other polysaccharides greatly enhance the formation of exolipase by Serratia marcescens

1979-06-01

U. Winkler , M Stuckmann

Among 21 different polysaccharides tested, 5 greatly enhanced the spontaneous and cyclic AMP-induced formation of exolipase: glycogen, hyaluronate, laminarin, pectin B, and gum arabic. These polysaccharides have in common the … Among 21 different polysaccharides tested, 5 greatly enhanced the spontaneous and cyclic AMP-induced formation of exolipase: glycogen, hyaluronate, laminarin, pectin B, and gum arabic. These polysaccharides have in common the tendency to form highly ordered networks because of the branching or helical arrangement, or both, of their molecules. None of the polysaccharides could be utilized by the cells as the sole carbon source. Strong lipid extraction of four different polysaccharides did not reduce their exolipase-enhancing efficacy. At a constant cell density the stimulation of exolipase formation by various concentrations of glycogen followed saturation kinetics, suggesting a limited number of "sites" for the glycogen to act. The active principle present in a solution of pectin was destroyed by degradation (beta-elimination) of the polymer. Hyaluronate lost its exolipase-enhancing activity by exhaustive hydrolysis with hyaluronidase but was resistant to proteinase K. Exopolysaccharide, isolated from growth medium of Serratia marcescens SM-6, enhanced the exolipase formation as efficiently as hyaluronate. The results of this work are discussed mainly in terms of the "detachment hypothesis."

View PDF Chat

Isolation and characterization of plant cell walls and cell wall components

1986-01-01

William S. York , Alan G. Darvill , Michael McNeil +2 more

Cellulose biosynthesis and function in bacteria

1991-03-01

Peter S. Ross , Raphael Mayer , Moshe Benziman

The current model of cellulose biogenesis in plants, as well as bacteria, holds that the membranous cellulose synthase complex polymerizes glucose moieties from UDP-Glc into beta-1,4-glucan chains which give rise … The current model of cellulose biogenesis in plants, as well as bacteria, holds that the membranous cellulose synthase complex polymerizes glucose moieties from UDP-Glc into beta-1,4-glucan chains which give rise to rigid crystalline fibrils upon extrusion at the outer surface of the cell. The distinct arrangement and degree of association of the polymerizing enzyme units presumably govern extracellular chain assembly in addition to the pattern and width of cellulose fibril deposition. Most evident for Acetobacter xylinum, polymerization and assembly appear to be tightly coupled. To date, only bacteria have been effectively studied at the biochemical and genetic levels. In A. xylinum, the cellulose synthase, composed of at least two structurally similar but functionally distinct subunits, is subject to a multicomponent regulatory system. Regulation is based on the novel nucleotide cyclic diguanylic acid, a positive allosteric effector, and the regulatory enzymes maintaining its intracellular turnover: diguanylate cyclase and Ca2(+)-sensitive bis-(3',5')-cyclic diguanylic acid (c-di-GMP) phosphodiesterase. Four genes have been isolated from A. xylinum which constitute the operon for cellulose synthesis. The second gene encodes the catalytic subunit of cellulose synthase; the functions of the other three gene products are still unknown. Exclusively an extracellular product, bacterial cellulose appears to fulfill diverse biological roles within the natural habitat, conferring mechanical, chemical, and physiological protection in A. xylinum and Sarcina ventriculi or facilitating cell adhesion during symbiotic or infectious interactions in Rhizobium and Agrobacterium species. A. xylinum is proving to be most amenable for industrial purposes, allowing the unique features of bacterial cellulose to be exploited for novel product applications.

View PDF Chat

Molecular Basis of Ca2+-Induced Gelation in Alginates and Pectins: The Egg-Box Model Revisited

2001-09-29

Isabelle Braccini , Serge Pérez

For many ionic polysaccharides, the ability to form gels in the presence of divalent cations such as calcium is the key to biological functions and technological applications. This is particularly … For many ionic polysaccharides, the ability to form gels in the presence of divalent cations such as calcium is the key to biological functions and technological applications. This is particularly true for alginates and pectins, where the regular occurrence of respectively α-l-(1−4)-guluronate residues and α-d-galacturonate residues generates ordered templates for polymer chain associations that are involved in physical gels. The molecular basis responsible for the strength and the stereospecificity of calcium interactions for the two polysaccharides were investigated in a previous paper (Braccini; et al. Carbohydr. Res. 1999, 119). In the present work, a novel molecular modeling procedure has been developed; it involves a pairing procedure that evaluates all the possible associations of the ordered polyuronate chains with calcium ions to form dimers. Starting from the stable ordered forms of polygalacturonate and polyguluronate, all possible ways to form Ca2+-bridged dimers were computed; the parallel and antiparallel relative arrangements of the chains were also considered. Despite the structural analogy between polyguluronate and polygalacturonate chains, significant differences at the level of chain−chain associations are found. The popular "egg box model" can still be referred to in the case of polyguluronate. However, it cannot be used to describe a pectate junction zone as the unique feature of two consecutive chelation site per repeat, that provides a favorable entropic contribution to the interchain association is not reproduced by this pioneering model. The body of these results corroborates the two-stage process in the mechanism of calcium gelation, where the formation of strongly linked dimer associations is followed by the formation of weak inter-dimer associations mainly governed by electrostatic interactions.

Cell wall disassembly in ripening fruit

2006-01-01

David A. Brummell

Fruit softening during ripening involves a coordinated series of modifications to the polysaccharide components of the primary cell wall and middle lamella, resulting in a weakening of the structure. Degradation … Fruit softening during ripening involves a coordinated series of modifications to the polysaccharide components of the primary cell wall and middle lamella, resulting in a weakening of the structure. Degradation of polysaccharides and alterations in the bonding between polymers cause an increase in cell separation and a softening and swelling of the wall, which, combined with alterations in turgor, bring about fruit softening and textural changes. A wide range in the extent of cell wall pectic modifications has been observed between species, whereas the depolymerisation of xyloglucan is relatively limited and more consistent. The earliest events to be initiated are usually a loss of pectic galactan side chains and the depolymerisation of matrix glycans, which may begin before ripening, followed by a loss of pectic arabinan side chains and pectin solubilisation. The depolymerisation of pectins may begin during early to mid-ripening, but is usually most pronounced late in ripening. However, some of these events may be absent or occur at very low levels in some species. Cell wall swelling may be related to a loosening of the xyloglucan–cellulose network and to pectin solubilisation, and these processes combined with the loss of pectic side chains increase wall porosity. An increase in wall porosity later in ripening may allow increased access of degradative enzymes to their substrates.

Botanical polysaccharides: Macrophage immunomodulation and therapeutic potential

2005-11-11

Igor A. Schepetkin , Mark T. Quinn

A new receptor for β-glucans

2001-09-01

Gordon D. Brown , Siamon Gordon

Syk-Dependent Cytokine Induction by Dectin-1 Reveals a Novel Pattern Recognition Pathway for C Type Lectins

2005-04-01

Neil C. Rogers , Emma Slack , Alexander D. Edwards +7 more

View PDF Chat

Pectin structure and biosynthesis

2008-05-16

Debra Mohnen

Growth of the plant cell wall

2005-11-01

Daniel J. Cosgrove

Elicitor- and wound-induced oxidative cross-linking of a proline-rich plant cell wall protein: A novel, rapid defense response

1992-07-01

Desmond Bradley , Per Kjellbom , Christopher J. Lamb

Applications of pectinases in the commercial sector: a review

2001-05-01

Des R. Kashyap , Pawan K. Vohra , S. Chopra +1 more

Visualization of Cellulose Synthase Demonstrates Functional Association with Microtubules

2006-04-21

Alexander R. Paredez , Christopher R. Somerville , David W. Ehrhardt

Expression of a functional yellow fluorescent protein fusion to cellulose synthase (CESA) in transgenic Arabidopsis plants allowed the process of cellulose deposition to be visualized in living cells. Spinning disk … Expression of a functional yellow fluorescent protein fusion to cellulose synthase (CESA) in transgenic Arabidopsis plants allowed the process of cellulose deposition to be visualized in living cells. Spinning disk confocal microscopy revealed that CESA complexes in the plasma membrane moved at constant rates in linear tracks that were aligned and were coincident with cortical microtubules. Within each observed linear track, complex movement was bidirectional. Inhibition of microtubule polymerization changed the fine-scale distribution and pattern of moving CESA complexes in the membrane, indicating a relatively direct mechanism for guidance of cellulose deposition by the cytoskeleton.

A method for the analysis of sugars in plant cell-wall polysaccharides by gas-liquid chromatography

1967-11-01

Peter Albersheim , Donald J. Nevins , Patricia D. English +1 more

(1→3)-β-d-Glucans as biological response modifiers: a review of structure-functional activity relationships

1995-01-01

John A. Bohn , James N. BeMiller

An improved sequence for broadband decoupling: WALTZ-16

1983-04-01

A.J. Shaka , James Keeler , T.A. Frenkiel +1 more

Biological interactions between polysaccharides and divalent cations: The egg‐box model

1973-05-15

Gregor T. Grant , Edwin R. Morris , David A. Rees +2 more

We han, e shown that spedfic binding of divalent cations to a polysaechafide polyelectro]ym, leading firm cohesion between the chains, can cause characteristic effects ~n ~e c~rcutar diehroism spectrum which … We han, e shown that spedfic binding of divalent cations to a polysaechafide polyelectro]ym, leading firm cohesion between the chains, can cause characteristic effects ~n ~e c~rcutar diehroism spectrum which are understandabb in terms of modem theo~, [ l ].For atginate, tiffs binding is a co-operative p,~otess that predominantly in~oNes consecuti~'e ~luronale residues.Some other systems ha~e now been inves,~igated in an attempt to formulate a general inSetpretafion of bio]ogics] phenomena of this type.T~e known streng~ and specificity of comp~exafion are explained m termg of an "'egg-box model" which ~s ,derN,ed from our measmemems, the known coordination geometries in mode] compounds, and the require-men~s roar ~ooperafivity.In pectin, • .themethyl este~ of poly(ga~acturonie acid), the interactions with ca~on.~ is relatively weak because ~he chains are unch~r~ed.In contrasl to the beha~onr of alginates, in which the amplitude diminishes w~th gelatben I ] ], the broad, positive, n ~ ~* gsnd 5_~ • ~he.cireular dickro~sm spectrum o'f rthe so] in-

View PDF Chat

Pectin: new insights into an old polymer are starting to gel

2005-11-16

William G. T. Willats , John Knox , Jørn Dalgaard Mikkelsen

Cereal arabinoxylans: advances in structure and physicochemical properties

1995-01-01

Marta S. Izydorczyk , Costas G. Βiliaderis

Microbial pectinolytic enzymes: A review

2005-05-25

Ranveer Singh Jayani , Shivalika Saxena , Reena Gupta

Regulation of cellulose synthesis in Acetobacter xylinum by cyclic diguanylic acid

1987-01-01

Peter S. Ross , Haim Weinhouse , Yehoshua Aloni +7 more

The cell wall: a carbohydrate armour for the fungal cell

2007-09-14

Jean‐Paul Latgé

Summary The cell wall is composed of a polysaccharide‐based three‐dimensional network. Considered for a long time as an inert exoskeleton, the cell wall is now seen as a dynamic structure … Summary The cell wall is composed of a polysaccharide‐based three‐dimensional network. Considered for a long time as an inert exoskeleton, the cell wall is now seen as a dynamic structure that is continuously changing as a result of the modification of culture conditions and environmental stresses. Although the cell wall composition varies among fungal species, chemogenomic comparative analysis have led to a better understanding of the genes and mechanisms involved in the construction of the common central core composed of branched β1,3 glucan‐chitin. Because of its essential biological role, unique biochemistry and structural organization and the absence in mammalian cells of most of its constitutive components, the cell wall is an attractive target for the development of new antifungal agents. Genomic as well as drug studies have shown that the death of the fungus can result from inhibition of cell wall polysaccharide synthases. To date, only β1,3 glucan synthase inhibitors have been launched clinically and many more targets remain to be explored.

The intercellular adhesin involved in biofilm accumulation of Staphylococcus epidermidis is a linear beta-1,6-linked glucosaminoglycan: purification and structural analysis

1996-01-01

Dietrich Mack , Werner Fischer , A Krokotsch +4 more

The primary attachment to polymer surfaces followed by accumulation in multilayered cell clusters leads to biofilm production of Staphylococcus epidermidis, which is thought to contribute to virulence in biomaterial-related infections. … The primary attachment to polymer surfaces followed by accumulation in multilayered cell clusters leads to biofilm production of Staphylococcus epidermidis, which is thought to contribute to virulence in biomaterial-related infections. We purified a specific polysaccharide antigen of biofilm-producing S. epidermidis 1457 and RP62A, which was recently shown to have a function in the accumulative phase of biofilm production by mediating intercellular adhesion (D. Mack, M. Nedelmann, A. Krokotsch, A. Schwarzkopf, J. Heesemann, and R. Laufs, Infect. Immun. 62:3244-3253, 1994). Following Sephadex G-200 gel filtration, this antigen was separated by Q-Sepharose chromatography into a major polysaccharide, polysaccharide I (> 80%), which did not bind to Q-Sepharose, and a minor polysaccharide, polysaccharide II (< 20%), which was moderately anionic. As shown by chemical analyses and nuclear magnetic resonance spectroscopy, polysaccharide I is a linear homoglycan of at least 130 beta-1,6-linked 2-deoxy-2-amino-D-glucopyranosyl residues. On average, 80 to 85% of them are N acetylated; the rest are non-N-acetylating and positively charged. Chain cleavage by deamination with HNO2 revealed a more or less random distribution of the non-N-acetylated glucosaminyl residues, with some prevalence of glucosaminyl-rich sequences. Cation-exchange chromatography separated molecular species whose content of non-N-acetylated glucosaminyl residues varied between 2 and 26%. Polysaccharide II is structurally related to polysaccharide I but has a lower content of non-N-acetylated D-glucosaminyl residues and contains phosphate and ester-linked succinate, rendering it anionic. Enzyme-linked immunosorbent assay inhibition with various monosaccharides revealed the beta-anomeric form and the acetylated amino group of the D-glucosaminyl residues as important for reactivity with the specific antiserum. The unbranched polysaccharide structure favors long-range contacts and interactions between polysaccharide strands and the cell wall and/or lectin-like proteins, leading to intercellular adhesion and biofilm accumulation. The structure of the polysaccharide is, so far, considered to be unique and, according to its function, is referred to as S. epidermidis polysaccharide intercellular adhesin (PIA).

View PDF Chat

Pectins: structure, biosynthesis, and oligogalacturonide-related signaling

2001-07-01

Brent Ridley , Malcolm A. O’Neill , Debra Mohnen

The structure, function, and biosynthesis of plant cell wall pectic polysaccharides

2009-06-03

Kerry Hosmer Caffall , Debra Mohnen

Dectin-1 Is A Major β-Glucan Receptor On Macrophages

2002-07-29

Gordon D. Brown , Philip R. Taylor , Delyth M. Reid +5 more

Zymosan is a β-glucan– and mannan-rich particle that is widely used as a cellular activator for examining the numerous responses effected by phagocytes. The macrophage mannose receptor (MR) and complement … Zymosan is a β-glucan– and mannan-rich particle that is widely used as a cellular activator for examining the numerous responses effected by phagocytes. The macrophage mannose receptor (MR) and complement receptor 3 (CR3) have historically been considered the major macrophage lectins involved in the nonopsonic recognition of these yeast-derived particles. Using specific carbohydrate inhibitors, we show that a β-glucan receptor, but not the MR, is a predominant receptor involved in this process. Furthermore, nonopsonic zymosan binding was unaffected by genetic CD11b deficiency or a blocking monoclonal antibody (mAb) against CR3, demonstrating that CR3 was not the β-glucan receptor mediating this activity. To address the role of the recently described β-glucan receptor, Dectin-1, we generated a novel anti–Dectin-1 mAb, 2A11. Using this mAb, we show here that Dectin-1 was almost exclusively responsible for the β-glucan–dependent, nonopsonic recognition of zymosan by primary macro-phages. These findings define Dectin-1 as the leukocyte β-glucan receptor, first described over 50 years ago, and resolves the long-standing controversy regarding the identity of this important molecule. Furthermore, these results identify Dectin-1 as a new target for examining the immunomodulatory properties of β-glucans for therapeutic drug design.

View PDF Chat

Toward a Systems Approach to Understanding Plant Cell Walls

2004-12-24

Chris Somerville , Štefan Bauer , Ginger Brininstool +7 more

One of the defining features of plants is a body plan based on the physical properties of cell walls. Structural analyses of the polysaccharide components, combined with high-resolution imaging, have … One of the defining features of plants is a body plan based on the physical properties of cell walls. Structural analyses of the polysaccharide components, combined with high-resolution imaging, have provided the basis for much of the current understanding of cell walls. The application of genetic methods has begun to provide new insights into how walls are made, how they are controlled, and how they function. However, progress in integrating biophysical, developmental, and genetic information into a useful model will require a system-based approach.

View PDF Chat

Molecular basis of intercellular adhesion in the biofilm‐forming Staphylococcus epidermidis

1996-06-01

Christine Heilmann , Oliver Schweitzer , Christiane Gerke +3 more

Summary The Staphylococcus epidermidis genes icaABC are involved in the synthesis of the polysaccharide intercellular adhesin (PIA), which is located mainly on the cell surface, as shown by immunofluorescence studies … Summary The Staphylococcus epidermidis genes icaABC are involved in the synthesis of the polysaccharide intercellular adhesin (PIA), which is located mainly on the cell surface, as shown by immunofluorescence studies with PIA‐specific antiserum. PIA was shown to be a linear β‐1,6‐linked glucosaminoglycan composed of at least 130 2‐deoxy‐2‐amino‐D‐glucopyrano‐syl residues of which 80–85% are N ‐acetylated, the rest being non‐ N ‐acetylated and positively charged. A transposon insertion in the icaABC gene cluster (ica , intercellular adhesion) led to the loss of several traits, such as the ability to form a biofilm on a polystyrene surface, cell aggregation, and PIA production. The mutant could be complemented by transformation with the IcaABC‐carrying plasmid pCN27. Transfer of pCN27 into the heterologous host Staphylococcus carnosus led to the formation of large cell aggregates, the formation of a biofilm on a glass surface, and PIA expression. The nucleotide sequence of icaABC suggests that the three genes are organized in an operon and that they are co‐transcribed from the mapped ica A promoter. Ica A contains four potential transmembrane helices, indicative of a membrane location. The deduced Ica A sequence shows similarity to those of polysaccharide‐polymerizing enzymes, the most pronounced being with a Rhizobium meliloti N ‐acetylglucosaminyltransferase involved in lipo‐chitin biosynthesis (22.5% overall identity and 37.4% overall similarity). This similarity suggests that Ica A has N‐ acetylglucosaminyltransferase activity in the formation

STRUCTURE AND BIOGENESIS OF THE CELL WALLS OF GRASSES

1996-06-01

Nicholas C. Carpita

The chemical structures of the primary cell walls of the grasses and their progenitors differ from those of all other flowering plant species. They vary in the complex glycans that … The chemical structures of the primary cell walls of the grasses and their progenitors differ from those of all other flowering plant species. They vary in the complex glycans that interlace and cross-link the cellulose microfibrils to form a strong framework, in the nature of the gel matrix surrounding this framework, and in the types of aromatic substances and structural proteins that covalently cross-link the primary and secondary walls and lock cells into shape. This review focuses on the chemistry of the unique polysaccharides, aromatic substances, and proteins of the grasses and how these structural elements are synthesized and assembled into dynamic and functional cell walls. Despite wide differences in wall composition, the developmental physiology of grasses is similar to that of all flowering plants. Grass cells respond similarly to environmental cues and growth regulators, exhibit the same alterations in physical properties of the wall to allow cell growth, and possess similar patterns of wall biogenesis during the development of specific cell and tissue types. Possible unifying mechanisms of growth are suggested to explain how grasses perform the same wall functions as other plants but with different constituents and architecture.

Structure and function of plant cell wall proteins.

1993-01-01

Allan M. Showalter

Plant cell walls are amazingly complex amalgams of carbohy? drates, proteins, lignin, water, and incrusting substances such as cutin, suberin, and certain inorganic compounds that vary among plant species, cell … Plant cell walls are amazingly complex amalgams of carbohy? drates, proteins, lignin, water, and incrusting substances such as cutin, suberin, and certain inorganic compounds that vary among plant species, cell types, and even neighboring cells. Developmental events and exposure to any of a number of abiotic and biotic stresses further increase this compositional and structural variation. Moreover, the dynamic nature and func? tions of plant cell walls in terms of growth and development, environmental sensing and signaling, plant defense, intercel? lular communication, and selective exchange interfaces are reflected in these variations. Much is currently known about the structure and metabolic regulation of the various cell wall components, but relatively little is known about their precise functions and intermolecular interactions. In this review, I will discuss the accumulated structural and regulatory data and the much more limited functional and in? termolecular interaction information on five plant cell wall protein classes. These five protein classes, listed in Table 1, include the extensins, the glycine-rich proteins (GRPs), the proline-rich proteins (PRPs), the solanaceous lectins, and the arabinogalactan proteins (AGPs). These five proteins may be evolutionarily related to one another, most obviously because each of them, with the exception of the GRPs, contains hydroxyproline, and less obviously in the case of the GRPs because this class has nucleotide sequence similarity to the extensins. For completeness, I should mention that these are not the only cell wall proteins that are known. Others exist, such as cysteine-rich thionins, 28and 70-kD water-regulated proteins, a histidine-tryptophan-rich protein, and many cell wall enzymes such as peroxidases, phosphatases, invertases, a-mannosidases, P-mannosidases, p-1,3-glucanases, (3-1,4glucanases, polygalacturonase, pectin methylesterases, malate dehydrogenase, arabinosidases, a-galactosidases, (3-galactosidases, |3-glucuronosidases, p-xylosidases, proteases, and ascorbic acid oxidase (Varner and Lin, 1989). However, the above five classes generally represent the most abundant, and to date, the most well-studied and widely documented, plant cell wall proteins. Before describing these five wall protein classes, I should point out that research on these individual proteins has oc? curred in several plant species, but relatively few examples exist where these cell wall proteins have been studied together in one plant, let alone in one particular plant organ or type of cell. Thus, data from one plant species are often extrapolated to represent the situation in other plant species. Although such extrapolations are usually valid, enough variations are now known that caution should be exercised in making or believing such claims.

View PDF Chat

Two endogenous proteins that induce cell wall extension in plants.

1992-11-01

Simon J. McQueen‐Mason , DanielM. Durachko , Daniel J. Cosgrove

Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude … Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

View PDF Chat

Cross-Linking of Matrix Polymers in the Growing Cell Walls of Angiosperms

1986-06-01

Stephen C. Fry

Crop loss due to soil salinization is an increasing threat to agriculture worldwide. This review provides an overview of cellular and physiological mechanisms in plant responses to salt. We place … Crop loss due to soil salinization is an increasing threat to agriculture worldwide. This review provides an overview of cellular and physiological mechanisms in plant responses to salt. We place cellular responses in a time- and tissue-dependent context ...Read More

Dectin-1 is required for β-glucan recognition and control of fungal infection

2006-12-10

Philip R. Taylor , S. Vicky Tsoni , Janet A. Willment +7 more

View PDF Chat

Cellulose Synthesis in Higher Plants

2006-07-06

Chris Somerville

Cellulose microfibrils play essential roles in the organization of plant cell walls, thereby allowing a growth habit based on turgor. The fibrils are made by 30 nm diameter plasma membrane … Cellulose microfibrils play essential roles in the organization of plant cell walls, thereby allowing a growth habit based on turgor. The fibrils are made by 30 nm diameter plasma membrane complexes composed of approximately 36 subunits representing at least three types of related CESA proteins. The complexes assemble in the Golgi, where they are inactive, and move to the plasma membrane, where they become activated. The complexes move through the plasma membrane during cellulose synthesis in directions that coincide with the orientation of microtubules. Recent, simultaneous, live-cell imaging of cellulose synthase and microtubules indicates that the microtubules exert a direct influence on the orientation of cellulose deposition. Genetic studies in Arabidopsis have identified a number of genes that contribute to the overall process of cellulose synthesis, but the role of these proteins is not yet known.

AspergillusEnzymes Involved in Degradation of Plant Cell Wall Polysaccharides

2001-12-01

Ronald P. de Vries , Jaap Visser

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 … 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.

View PDF Chat

Pectin, a versatile polysaccharide present in plant cell walls

2009-03-12

Alphons G. J. Voragen , Gerd‐Jan Coenen , René Verhoef +1 more

Pectin or pectic substances are collective names for a group of closely associated polysaccharides present in plant cell walls where they contribute to complex physiological processes like cell growth and … Pectin or pectic substances are collective names for a group of closely associated polysaccharides present in plant cell walls where they contribute to complex physiological processes like cell growth and cell differentiation and so determine the integrity and rigidity of plant tissue. They also play an important role in the defence mechanisms against plant pathogens and wounding. As constituents of plant cell walls and due to their anionic nature, pectic polysaccharides are considered to be involved in the regulation of ion transport, the porosity of the walls and in this way in the control of the permeability of the walls for enzymes. They also determine the water holding capacity. The amount and composition of pectic molecules in fruits and vegetables and other plant produce strongly determine quality parameters of fresh and processed food products. Pectin is also extracted from suitable agro-by-products like citrus peel and apple pomace and used in the food industry as natural ingredients for their gelling, thickening, and stabilizing properties. Some pectins gain more and more interest for their health modulating activities. Endogenous as well as exogenous enzymes play an important role in determining the pectic structures present in plant tissue, food products, or ingredients at a given time. In this paper functional and structural characteristics of pectin are described with special emphasis on the structural elements making up the pectin molecule, their interconnections and present models which envisage the accommodation of all structural elements in a macromolecule. Attention is also given to analytical methods to study the pectin structure including the use of enzymes as analytical tools.

View PDF Chat

Structural models of primary cell walls in flowering plants: consistency of molecular structure with the physical properties of the walls during growth

1993-01-01

Nicholas C. Carpita , David M. Gibeaut

Summary Advances in determination of polymer structure and in preservation of structure for electron microscopy provide the best view to date of how polysaccharides and structural proteins are organized into … Summary Advances in determination of polymer structure and in preservation of structure for electron microscopy provide the best view to date of how polysaccharides and structural proteins are organized into plant cell walls. The walls that form and partition dividing cells are modified chemically and structurally from the walls expanding to provide a cell with its functional form. In grasses, the chemical structure of the wall differs from that of all other flowering plant species that have been examined. Nevertheless, both types of wall must conform to the same physical laws. Cell expansion occurs via strictly regulated reorientation of each of the wall's components that first permits the wall to stretch in specific directions and then lock into final shape. This review integrates information on the chemical structure of individual polymers with data obtained from new techniques used to probe the arrangement of the polymers within the walls of individual cells. We provide structural models of two distinct types of walls in flowering plants consistent with the physical properties of the wall and its components.

View PDF Chat

Cell Wall Metabolism in Response to Abiotic Stress

2015-02-16

Hyacinthe Le Gall , Florian Philippe , Jean-Marc Domon +3 more

This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of … This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions.

View PDF Chat

Pectin methylesterases: cell wall enzymes with important roles in plant physiology

2001-09-01

Fabienne Micheli

FT-IR study of plant cell wall model compounds: pectic polysaccharides and hemicelluloses

2000-10-01

Marta Kačuráková

RHAMNOGALACTURONAN II: Structure and Function of a Borate Cross-Linked Cell Wall Pectic Polysaccharide

2004-04-29

Malcolm A. O’Neill , Tadashi Ishii , Peter Albersheim +1 more

Rhamnogalacturonan II (RG-II) is a structurally complex pectic polysaccharide that was first identified in 1978 as a quantitatively minor component of suspension-cultured sycamore cell walls. Subsequent studies have shown that … Rhamnogalacturonan II (RG-II) is a structurally complex pectic polysaccharide that was first identified in 1978 as a quantitatively minor component of suspension-cultured sycamore cell walls. Subsequent studies have shown that RG-II is present in the primary walls of angiosperms, gymnosperms, lycophytes, and pteridophytes and that its glycosyl sequence is conserved in all vascular plants examined to date. This is remarkable because RG-II is composed of at least 12 different glycosyl residues linked together by more than 20 different glycosidic linkages. However, only a few of the genes and proteins required for RG-II biosynthesis have been identified. The demonstration that RG-II exists in primary walls as a dimer that is covalently cross-linked by a borate diester was a major advance in our understanding of the structure and function of this pectic polysaccharide. Dimer formation results in the cross-linking of the two homogalacturonan chains upon which the RG-II molecules are constructed and is required for the formation of a three-dimensional pectic network in muro. This network contributes to the mechanical properties of the primary wall and is required for normal plant growth and development. Indeed, changes in wall properties that result from decreased borate cross-linking of pectin may lead to many of the symptoms associated with boron deficiency in plants.

Chemistry and uses of pectin — A review

1997-02-01

B. R. Thakur , Rakesh Kumar Singh , Avtar K. Handa +1 more

Abstract Pectin is an important polysaccharide with applications in foods, Pharmaceuticals, and a number of other industries. Its importance in the food sector lies in its ability to form gel … Abstract Pectin is an important polysaccharide with applications in foods, Pharmaceuticals, and a number of other industries. Its importance in the food sector lies in its ability to form gel in the presence of Ca2+ ions or a solute at low pH. Although the exact mechanism of gel formation is not clear, significant progress has been made in this direction. Depending on the pectin, coordinate bonding with Ca2+ ions or hydrogen bonding and hydrophobic interactions are involved in gel formation. In low‐methoxyl pectin, gelation results from ionic linkage via calcium bridges between two carboxyl groups belonging to two different chains in close contact with each other. In high‐methoxyl pectin, the cross‐linking of pectin molecules involves a combination of hydrogen bonds and hydrophobic interactions between the molecules. A number of factors—pH, presence of other solutes, molecular size, degree of methoxylation, number and arrangement of side chains, and charge density on the molecule— influence the gelation of pectin. In the food industry, pectin is used in jams, jellies, frozen foods, and more recently in low‐calorie foods as a fat and/or sugar replacer. In the pharmaceutical industry, it is used to reduce blood cholesterol levels and gastrointestinal disorders. Other applications of pectin include use in edible films, paper substitute, foams and plasticizers, etc. In addition to pectolytic degradation, pectins are susceptible to heat degradation during processing, and the degradation is influenced by the nature of the ions and salts present in the system. Although present in the cell walls of most plants, apple pomace and orange peel are the two major sources of commercial pectin due to the poor gelling behavior of pectin from other sources. This paper briefly describes the structure, chemistry of gelation, interactions, and industrial applications of pectin.

Biological activities and pharmaceutical applications of polysaccharide from natural resources: A review

2017-12-08

Yue Yu , Mingyue Shen , Qianqian Song +1 more

Cell wall metabolism in fruit softening and quality and its manipulation in transgenic plants

2001-01-01

David A. Brummell , Mark H. Harpster

Hemicelluloses

2010-05-04

Henrik Vibe Scheller , Peter Ulvskov

Hemicelluloses are polysaccharides in plant cell walls that have beta-(1-->4)-linked backbones with an equatorial configuration. Hemicelluloses include xyloglucans, xylans, mannans and glucomannans, and beta-(1-->3,1-->4)-glucans. These types of hemicelluloses are present … Hemicelluloses are polysaccharides in plant cell walls that have beta-(1-->4)-linked backbones with an equatorial configuration. Hemicelluloses include xyloglucans, xylans, mannans and glucomannans, and beta-(1-->3,1-->4)-glucans. These types of hemicelluloses are present in the cell walls of all terrestrial plants, except for beta-(1-->3,1-->4)-glucans, which are restricted to Poales and a few other groups. The detailed structure of the hemicelluloses and their abundance vary widely between different species and cell types. The most important biological role of hemicelluloses is their contribution to strengthening the cell wall by interaction with cellulose and, in some walls, with lignin. These features are discussed in relation to widely accepted models of the primary wall. Hemicelluloses are synthesized by glycosyltransferases located in the Golgi membranes. Many glycosyltransferases needed for biosynthesis of xyloglucans and mannans are known. In contrast, the biosynthesis of xylans and beta-(1-->3,1-->4)-glucans remains very elusive, and recent studies have led to more questions than answers.

Structure–function relationships of immunostimulatory polysaccharides: A review

2015-06-13

Sónia S. Ferreira , Cláudia P. Passos , Pedro Madureira +2 more

View PDF Chat

Photosynthesis and stress tolerance: cell walls at the cross-road

2025-06-24

María José Clemente‐Moreno , Carlos Frey , Lidia López‐Serrano +3 more | Journal of Experimental Botany

Abstract The cell wall (CW) plays a pivotal role in plant responses to abiotic stress and the regulation of photosynthesis. Modifications in CW composition and structure can enhance drought tolerance … Abstract The cell wall (CW) plays a pivotal role in plant responses to abiotic stress and the regulation of photosynthesis. Modifications in CW composition and structure can enhance drought tolerance and other stress responses, but often at the expense of photosynthetic efficiency. This review explores the complex relationship between the CW, photosynthesis and stress tolerance. We describe how changes in CW composition, such as variations in pectin, hemicellulose, and lignin contents, affect CO2 diffusion and, consequently, mesophyll conductance (gm), but also their known effects driving stress tolerance through mechanisms like altered cell wall elasticity and water retention, and signalling stress response pathways. New analytical and molecular tools offer an unprecedented set of possibilities to develop biotechnological strategies for sustainable agriculture. We conclude that the CW represents a promising target for crop improvement through genetic engineering and ecophysiological studies; but further research is needed to fully understand the underlying mechanisms and avoid unintended effects on photosynthesis and growth.

Mechanism of Fermented-Litchi Polysaccharide Promoting Exopolysaccharide Production by Weissella confusa

2025-06-23

Teng‐Gen Hu , Feng‐Xiang Tan , Bo Zou +6 more | Journal of Agricultural and Food Chemistry

Fermented-litchi polysaccharide (Lzp) has been demonstrated to enhance the production of exopolysaccharides (EPS) in Weissella confusa in our previous study. To elucidate the underlying mechanisms, the resulting EPS was identified … Fermented-litchi polysaccharide (Lzp) has been demonstrated to enhance the production of exopolysaccharides (EPS) in Weissella confusa in our previous study. To elucidate the underlying mechanisms, the resulting EPS was identified as a homopolysaccharide primarily composed of →6)-α-d-Glcp-(1→. Integrated metabolomics and transcriptomics analyses identified 19 differential metabolites and 60 differential genes associated with the effects of Lzp. Specifically, 13 extracellular metabolites were enriched in ABC transporters, starch and sucrose metabolism, and glycerophospholipid metabolism, while 6 intracellular metabolites were linked to aminoacyl-tRNA biosynthesis and pyrimidine metabolism. Transcriptomics revealed upregulation of key genes in the ABC transporter pathway (msmX, ugpA, ugpE, and pstS) and sucrose synthase-dependent pathway (sacA and sucA), facilitating the transport of EPS precursors and their extracellular assembly. Notably, Lzp-derived galactose and arabinose were transformed into UDP-glucose via the Leloir pathway and the pentose phosphate pathway, respectively, thus enhancing the availability of UDP-glucose for EPS synthesis. Validation via qRT-PCR confirmed the regulatory roles of these genes. Furthermore, genes involved in pyrimidine metabolism (pyrB, pyrE, etc.) were modulated to regulate nucleotide synthesis, indirectly supporting EPS polymerization. This study unveils Lzp's multi-target mechanism, coordinating carbohydrate metabolism, transporter activity, and transcriptional regulation to enhance EPS production, offering a foundation for industrial optimization using natural polysaccharides.

An ABA–ROP toggle switch orchestrates xylem differentiation and cell wall patterning

2025-06-23

Valentina Elettra Alberti , Daria Bloch , Erik Gengel +3 more | Proceedings of the National Academy of Sciences

The mutual antagonistic signaling of abscisic acid (ABA) and ROP GTPases highlights an intersection between stress responses and pattern formation. Previously, we have shown that signaling of ABA in the … The mutual antagonistic signaling of abscisic acid (ABA) and ROP GTPases highlights an intersection between stress responses and pattern formation. Previously, we have shown that signaling of ABA in the endodermis leads to protoxylem (PX) differentiation. In this study, we demonstrate that ROPs suppress PX differentiation in the roots of both Arabidopsis and tomato. Fourier transform and Shannon's entropy show that endodermal ABA signaling controls the periodicity and overall order of PX secondary cell wall (SCW) coils in an ROP-dependent manner. Correspondingly, in the PX, GFP-ROP11 is initially dispersed and gradually becomes distributed in an oscillatory fashion with a periodicity corresponding to that of the SCW coils. Oryzalin treatments disrupt the frequency and increase the entropy of the GFP-ROP11 signal, suggesting that microtubules delimit ROP distribution. Signaling of ABA in the endodermis encourages the enlargement of metaxylem SCW pits, while ABA signaling in the stele limits this enlargement. Pit size and density are decreased in ROP mutants while ABA enhances ROP11 expression in the stele and broadens its distribution in the endodermis. Taken together, non-cell-autonomous and cell-autonomous interactions between ABA and ROPs regulate xylem differentiation and SCW patterning.

Salinity stress effects on cell wall components and pectin localization in spinach (Spinacia oleracea L.)

2025-06-23

Jia Liu , Shuoshuo Liang , Yafei Shi +6 more | Plant Growth Regulation

Pharmaceutical application of beta-glucan: a comprehensive overview

2025-06-20

Pooja Anand Mundada , Hitendra S. Mahajan | Future Journal of Pharmaceutical Sciences

Abstract Background Beta-glucan (BG) is a diverse group of polysaccharides widely distributed in nature, including fungi, algae, bacteria, and cereals. Due to its unique physicochemical and biological properties, BG has … Abstract Background Beta-glucan (BG) is a diverse group of polysaccharides widely distributed in nature, including fungi, algae, bacteria, and cereals. Due to its unique physicochemical and biological properties, BG has gained significant attention in various fields, such as pharmaceuticals, cosmetics, nutraceuticals, and agriculture. Main body This article provides a comprehensive overview of BG’s applications and highlights their potential benefits in pharmaceuticals. BG has demonstrated significant potential as an immunomodulatory agent in the pharmaceutical field. They can stimulate the immune system, enhance the activity of macrophages, and increase the production of cytokines. This makes BG valuable in developing immunotherapeutic drugs, vaccine adjuvants, and wound-healing formulations. Additionally, BG has shown anticancer properties and has been investigated as a potential cancer prevention and treatment agent. Conclusion Overall, this overview highlights the diverse applications of BG in pharmaceuticals. Their functional and bioactive properties make them versatile ingredients in pharmaceuticals. The understanding of BG structure–function relationships and their mechanisms of action continues to expand, paving the way for future novel and innovative uses of these polysaccharides.

Purification, Structural Characterization, and Immunomodulatory Activity of an Exopolysaccharide from Acetilactobacillus jinshanensis BJ01 in Baijiu Fermentation Grains

2025-06-20

Tian Tian , Bo Wan , Ying Xiong +7 more | Foods

This study aims to identify the chemical structure and immunomodulatory activity of exopolysaccharides (EPSs) from Acetilactobacillus jinshanensis BJ01 and suggest its potential applications in the pharmaceutical field and as functional … This study aims to identify the chemical structure and immunomodulatory activity of exopolysaccharides (EPSs) from Acetilactobacillus jinshanensis BJ01 and suggest its potential applications in the pharmaceutical field and as functional food additives. The EPS-1 produced by A. jinshanensis BJ01 was purified using column chromatography. The lyophilized powder obtained by vacuum freeze-drying was used for structural characterization and immunomodulatory activity analysis. Gel permeation chromatography (GPC) determined its molecular weight as 156.58 kDa. High-performance anion-exchange chromatography (HPAEC) identified that the EPS-1 is composed of mannose, xylose, and glucose. The structural characterization of EPS-1 by gas chromatography–mass spectrometry (GC-MS) and 1D/2D nuclear magnetic resonance (NMR) spectroscopy demonstrated that EPS-1 is primarily composed of α-D-Manp-(1→, →2,6)-α-D-Manp-(1→, →2)-α-D-Manp-(1→, and →3)-α-D-Manp-(1→. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) illustrated that EPS-1 exhibited a round, flake-like morphology. In vitro experiments with RAW264.7 macrophages demonstrated the high immunomodulatory activity of EPS-1. Significant upregulation of iNOS, IL-6, and TNF-α mRNA levels was confirmed by qRT-PCR (p < 0.05). Western blotting revealed that EPS-1 (6.25 μg/mL) induced phosphorylation of NF-κB (p65, IκBα) and MAPK (ERK) signaling proteins. This study provides the first structural and immunomodulatory characterization of an exopolysaccharide from A. jinshanensis BJ01, highlighting its potential as a novel immune adjuvant.

Identification and Expression Profiles of Xyloglucan Endotransglycosylase/Hydrolase Family in Response to Drought Stress in Larix kaempferi

2025-06-19

Yan Jiang , Ruodong Qin , Yuqian Wang +2 more | Plants

Xyloglucan endotransglucosylase/hydrolase (XTH) is a crucial enzyme in plant cell wall remodeling, which contributes to plant growth, development, and stress response. Based on the transcriptome data of Larix kaempferi, this … Xyloglucan endotransglucosylase/hydrolase (XTH) is a crucial enzyme in plant cell wall remodeling, which contributes to plant growth, development, and stress response. Based on the transcriptome data of Larix kaempferi, this study identified and analyzed 16 XTH genes. Sequence alignment and phylogenetic analysis indicated that the LkXTH gene family can be divided into three subfamilies, namely the Early Diverging Group, Group I/II, and Group III, all of which share highly conserved motifs and structural features. Expression profiling demonstrated that LkXTH genes are actively expressed in the roots, stems, and leaves of L. kaempferi. Under drought stress, the expression of LkXTH1, LkXTH2, LkXTH3, LkXTH4, LkXTH6, LkXTH14, LkXTH15, LkXTH17, and LkXTH18 increased rapidly in roots. Meanwhile, the expression levels of LkXTH5, LkXTH7, LkXTH8, and LkXTH13 exhibited significant upregulation in leaves. Notably, LkXTH11 and LkXTH16 significantly increased in both roots and leaves, with a more pronounced increase in leaves, but LkXTH10 displayed significant upregulation in the stems. Furthermore, the heterologous expression of LkXTH1 and LkXTH17 in yeast significantly enhances drought tolerance. These findings indicate that individual LkXTH genes exhibit distinct organ-specific responses to drought stress, thereby advancing our understanding of their functional roles in larch drought response.

Comprehensive genome-wide identification and functional analysis of the GT8 gene family in Eucalyptus Grandis

2025-06-19

Ying Jie , Liwan Liu , Linsi Li +3 more | Frontiers in Plant Science

Introduction The Glycosyltransferase 8 (GT8) family is critically involved in plant cell wall synthesis, yet exhibits significant functional divergence among its members. Despite its importance, systematic characterization of GT8 genes … Introduction The Glycosyltransferase 8 (GT8) family is critically involved in plant cell wall synthesis, yet exhibits significant functional divergence among its members. Despite its importance, systematic characterization of GT8 genes in woody plants remains limited. This study aims to comprehensively analyze the GT8 gene family in Eucalyptus grandis to elucidate its role in cell wall biosynthesis. Methods We employed bioinformatics tools to mine the E. grandis whole-genome database. A systematic analysis was conducted, including phylogenetic classification, assessment of physicochemical properties, subcellular localization prediction, gene structure annotation, chromosome mapping, and cis-acting element identification in promoter regions. Results Fifty-two GT8 family members were identified and classified into four subfamilies: GAUT, GATL, GolS, and PGSIP. Protein molecular weights ranged from 15.75 to 185.00 kD (mean: 49.08 kD). Genes were dispersed across all chromosomes except chromosomes 3 and 7. Promoter analysis revealed ubiquitous hormone-responsive cis-elements and prevalent light-responsive elements. Phylogenetic inference suggested that EgGUX02 and EgGUX04 may mediate glucuronic acid (GlcA) incorporation into xylan side chains, while EgGAUT1 and EgGAUT12 are likely direct contributors to xylan and pectin biosynthesis. Discussion This study provides the first genome-wide functional annotation of the GT8 family in E. grandis, revealing subfamily-specific roles in cell wall polymer synthesis. The enrichment of stress- and hormone-responsive promoter elements implies regulatory complexity in cell wall remodeling. Our findings establish a foundation for targeted manipulation of xylan and pectin biosynthesis in woody plants, with potential applications in biomass engineering.

Polysaccharide Composites with Rosa canina for Sustained Anti-Inflammatory Skin Therapy

2025-06-19

Narcis Anghel , Irina Apostol , Ioana Plaesu +4 more | Polymers

This study presents novel skin-compatible biomaterials based on guar gum and dextran sulfate matrices, incorporating softwood lignin, lignin esterified with aspartic acid, and Rosa canina extract. The materials were prepared … This study presents novel skin-compatible biomaterials based on guar gum and dextran sulfate matrices, incorporating softwood lignin, lignin esterified with aspartic acid, and Rosa canina extract. The materials were prepared via casting and evaluated for physicochemical, mechanical, and biological properties. Spectroscopic analyses confirmed successful lignin esterification, with new carbonyl and amide peaks and a nitrogen signal (3.83%) detected. Rosa canina extract enhanced the Young's modulus from 1.42 MPa to 3.18 MPa and reduced elongation at break from 34.88 mm to 25.19 mm. The combination of esterified lignin and Rosa canina showed the greatest mechanical reinforcement (3.74 MPa modulus, 23.78 mm elongation). Swelling capacity decreased from 0.40 to 0.23 g water/g material and followed pseudo-second-order kinetics (R2 = 0.991-0.998). The release of Rosa canina bioactives followed the Makoid-Banakar model, indicating a transition from rapid to sustained release. All formulations exhibited anti-inflammatory activity with over 45% protein denaturation inhibition, peaking at 61.58% for the Rosa canina-only sample. In vitro biocompatibility assays demonstrated over 80% cell viability, confirming the potential of these biomaterials for dermal applications.

Agrobacterium-mediated genetic transformation of chia (Salvia hispanica L.), a rich source of omega-3 fatty acid

2025-06-18

N. Nikhil Anirudh , P. Haritha , R. V. Sreedhar | Transgenic Research

Ultrasound-assisted Polysaccharide Extraction from Hordei Fructus Germinatus and its Stir-frying Product: Optimization, Structural Characterization and Bioactivities

2025-06-18

Shuang Liu , Na Kong , Qingjun Li +2 more | LWT

Fundamental interactions between pectin and cellulose nanocrystals: a molecular dynamics simulation

2025-06-18

Xiawa Wu , Anamika Prasad | Cellulose

Polysaccharides from Chrysanthemum morifolium: Optimization of ultrafiltration isolation and anti-oxidant and anti-inflammatory effects

2025-06-18

Hua Hang , Dongsheng Du , Yue Xing +4 more | International Journal of Biological Macromolecules

Chemical structure of β-glucans from the mushrooms of Lactarius spp. for development of polysaccharide-coated liposomes

2025-06-18

Mariana M. de Carvalho , Julienne Meyer , Wafa Subhi Abahra +3 more | Carbohydrate Polymer Technologies and Applications

The Chemical Profiling and Immunological Activity of Polysaccharides from the Rhizome of Imperata cylindrica Using Hot Water Extraction

2025-06-18

Mengge Sun , Jiajie Chen , Jiamin Xu +3 more | Molecules

To investigate the immunomodulatory activity of polysaccharides derived from the rhizome of Imperata cylindrica, polysaccharides (IRPs-H) were extracted using hot water extraction and further purified via DEAE-52 ion-exchange chromatography, yielding … To investigate the immunomodulatory activity of polysaccharides derived from the rhizome of Imperata cylindrica, polysaccharides (IRPs-H) were extracted using hot water extraction and further purified via DEAE-52 ion-exchange chromatography, yielding three fractions: IRPs-H1, IRPs-H2, and IRPs-H3. The structural features of these fractions were characterized by Fourier-transform infrared spectroscopy (FT-IR), high-performance gel permeation chromatography (HPGPC), atomic force microscopy (AFM), and thermogravimetric analysis (TGA). Their immunological activities were evaluated in vitro. All three fractions were identified as neutral pyranose-type polysaccharides, primarily composed of glucose and xylose, exhibiting good thermal stability and lacking long-chain structures. In vitro assays using RAW264.7 macrophages demonstrated that these polysaccharides promoted cell proliferation (50-800 μg/mL), enhanced phagocytic activity, and induced morphological changes characteristic of macrophage activation, including irregular shapes and pseudopod formation. ELISA and flow cytometry analyses revealed dose-dependent increases in nitric oxide (NO), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and reactive oxygen species (ROS) levels. Notably, the IRPs-H3 fraction stimulated TNF-α and IL-6 production to levels of 438.02 ± 14.14 pg/mL and 30.13 ± 1.27 pg/mL, respectively, which were comparable to those induced by lipopolysaccharide (LPS), the positive control (460.83 ± 16.10 pg/mL and 31.87 ± 1.72 pg/mL, respectively). These results suggest that polysaccharides extracted from the rhizome of Imperata cylindrica possess significant immunostimulatory properties and hold potential for development as functional food ingredients or immune-enhancing agents.

Plasma-activated water: A novel approach to modulating main pectin, hemicellulose and cellulose metabolism in goji berry cell walls

2025-06-18

Kaiping Cong , Tingting Li , Caie Wu +4 more | Postharvest Biology and Technology

Genome-wide identification of the pectin methylesterase (PME) gene family in watermelon (Citrullus lanatus) and the role in the regulation of fruit softening

2025-06-18

Chang Li , Miaomiao Yang , Shuang Pei +6 more | Research Square (Research Square)

<title>Abstract</title> The pectin methylesterase (PME) genes are key genes that regulate the hydrolysis and structural reorganization of pectin components in fruits and play indispensable roles in the structure and composition … <title>Abstract</title> The pectin methylesterase (PME) genes are key genes that regulate the hydrolysis and structural reorganization of pectin components in fruits and play indispensable roles in the structure and composition of plant cell walls. Therefore, elucidating the changes that occur in <italic>ClPME</italic> during the critical period of fruit development in watermelon is highly important for studying the regulatory mechanism of <italic>ClPME</italic>-mediated fruit softening in watermelon. In conjunction with the <italic>Arabidopsis thaliana</italic> PME protein structural domains, 72 members of the <italic>ClPME</italic> gene family were jointly identified from the whole genome of watermelon and analyzed for the physicochemical properties and phylogenetic relationships of their encoded proteins. Based on the transcriptome data, the expression patterns of <italic>ClPME</italic>in watermelon fruits at different developmental periods were analyzed. An enzyme activity assay revealed that the PME enzyme activities significantly differed among watermelons of different fruit hardness varieties. qRT‒PCR was used to analyze the relative expression of key <italic>ClPME</italic> genes during the critical period of fruit development. After transient silencing of the homologous genes of key <italic>ClPME</italic> genes in tomato, significant differential changes in tomato fruit hardness occurred. These genes were investigated for their possible role in watermelon fruit development. Moreover, the expression patterns of the key <italic>ClPME</italic> genes in response to different phytohormone sprays were different, suggesting that the mechanisms of watermelon fruit hardness changes in response to different phytohormone sprays. These findings provide a theoretical basis for elucidating the role and molecular genetic mechanism of the <italic>ClPME</italic> gene family in watermelon fruit hardness changes.

A Fasciclin-like Arabinogalactan protein OsFLA8 is involved in Casparian strip formation and salt tolerance in rice

2025-06-17

Dong Chao , Xiaoqian Sun , Xingxiang Chen +7 more | Plant Physiology and Biochemistry

Unraveling the link between structural properties of polysaccharides and anti-inflammatory activity: A review

2025-06-17

Yuanhao Qiu , Aoying Zhang , Xiuning Lian +5 more | Carbohydrate Research

Isolation and characterisation of cell wall polysaccharides from taewa (Māori potatoes; Solanum tuberosum L.)

2025-06-17

Cara A. Luiten , Simon F.R. Hinkley , Nick Roskruge +5 more | Food Hydrocolloids

Comprehensive Identification of Auxin Response Factor Gene Family and Their Expression Profiles Under Lanthanum Stress in Amorphophallus konjac

2025-06-16

Xiaoxian Li , Huiyan Huang , Jiaxin Shen +3 more | Horticulturae

Amorphophallus konjac is an economically important horticultural crop, valued for its corms as both a traditional medicine and a food source. The auxin transcription factor (ARF) family plays pivotal roles … Amorphophallus konjac is an economically important horticultural crop, valued for its corms as both a traditional medicine and a food source. The auxin transcription factor (ARF) family plays pivotal roles in auxin signaling and the processes of the morphogenesis of tissues and organs. However, the specific role of the ARF gene family in the regulation of corms remains unknown. In this study, we identified 23 AkARF genes unevenly distributed across 11 chromosomes in A. konjac. Phylogenetic analysis classified these proteins into four distinct clades, with members of the same group sharing conserved gene structures. Expression profiling demonstrated AkARF genes were expressed in a tissue-specific and spatio-temporal manner. Furthermore, lanthanum treatment significantly increased corm biomass and endogenous auxin levels (peak at 20 mg·L−1; p < 0.05). Transcriptome and qRT-PCR analyses revealed coordinated expression of AkARF6/13/14/16/20 with corm biomass accumulation. Pearson’s correlation analysis further confirmed positive correlations of AkARF6/13 with auxin content (p < 0.05). These results suggested the potential regulatory roles of AkARF6/13 in auxin-mediated corm development. This study provides the potential functional role of ARF-mediated growth and development of corms in A. konjac.

Cellulose synthase TaCESA7 negatively regulates wheat resistance to stripe rust by reducing cell wall lignification

2025-06-16

Yanqin Zhang , Longhui Yu , Shuangyuan Guo +7 more | Stress Biology

Abstract Cellulose is synthesized by cellulose synthases (CESAs) in plasma membrane-localized complexes, which act as a central component of the cell wall and influence plant growth and defense responses. Puccinia … Abstract Cellulose is synthesized by cellulose synthases (CESAs) in plasma membrane-localized complexes, which act as a central component of the cell wall and influence plant growth and defense responses. Puccinia striiformis f. sp. tritici ( Pst ) is an airborne fungus that causes stripe rust to seriously endanger wheat production. In this study, a CESA gene, TaCESA7 , was identified to be significantly up-regulated during Pst infection in wheat ( Triticum aestivum L.). TaCESA7 was localized on the plasma membrane in dimeric form, and the dimers interact to assemble into CESA complexes. Stable overexpression of TaCESA7 weakened the resistance of wheat to Pst . Knockdown of TaCESA7 by RNA interference (RNAi) and virus-induced gene silencing led to restricted hyphal spread, increased necrotic area, and simultaneously promotes reactive oxygen species (ROS) accumulation and the expression of pathogenesis-related (PR) genes. Transcriptome analysis of TaCESA7 -RNAi plants revealed that the up-regulated genes were significantly enriched in the phenylpropanoid biosynthesis and plant-pathogen interaction pathways. Moreover, silencing TaCESA7 promoted the deposition of lignin and the expression of genes related to lignin synthesis. CRISPR-Cas9-mediated inactivation of TaCESA7 in wheat could confer broad-spectrum resistance against Pst without affecting agronomic traits. These findings provide valuable candidate gene resources and guidance for molecular breeding to improve the resistance of wheat to fungal disease.

A New Kinetic Model for Pectin Extraction from Grapefruit Peel Using Delayed Differential Equations

2025-06-16

María Laura Montoro , Nadia Pantano , Cecilia Fernández +3 more | Processes

The objective of this study is to develop a kinetic model that incorporates time-delay mechanisms to describe the gradual release behavior of pectin. Three models were used: modified Peleg, logistic, … The objective of this study is to develop a kinetic model that incorporates time-delay mechanisms to describe the gradual release behavior of pectin. Three models were used: modified Peleg, logistic, and second-order linear with time delay (SOPDT), to represent the extraction kinetics of grapefruit peels at 60, 70, and 90 °C. Model fitting was performed using a hybrid methodology combining Monte Carlo simulations with genetic algorithms. The SOPDT model provided the best fit, with the lowest squared error values (J = 7.06 at 60 °C, 5.63 at 70 °C, and 8.71 at 90 °C), requiring only two parameters to represent the entire process. In contrast, the other models required six. The maximum pectin yield reached over 120% at 90 °C, compared to <80% at lower temperatures. These results demonstrate the potential of the SOPDT model for efficient process description and control.

Effects of fermented polyphenols from Lonicera caerulea on Streptococcus mutans pathogenicity: Exopolysaccharide structure and quorum sensing regulation

2025-06-16

Yanxin Ren , Xiaohang Zhou , Baiyan Cai +3 more | International Journal of Biological Macromolecules

Mechanically Ultra-Strong Pectin with Enhanced Electro-Optic Properties for Bioelectronics via Low-Temperature Supercritical Self-Cross-Linking

2025-06-16

Kuan‐Chang Chang , Xinqing Duan , Yu Jiang +3 more | ACS Sustainable Chemistry & Engineering

Structural and physicochemical characterization, technological properties, and prebiotic potential of an acidic polysaccharide extracted from the aerial parts of Eryngium billardieri

2025-06-16

Sara Darvishi Aghajani , Sabihe Soleimanian‐Zad | European Food Research and Technology

ACCUMULATION OF LIGNIN AND PHENOLIC ACIDS IN THE CELL WALL OF CUCUMBER HYPOCOTYLS UNDER THE INFLUENCE OF PECTIN OLIGOSACCHARIDES

2025-06-13

N. Yu. Selivanov , O. G. Selivanova , Anna Alekseevna Galitskaya +1 more | chemistry of plant raw material

The effectiveness of the use of citrus pectin fermentolysis products to stimulate the manifestations of phytoimmunity and resistance to abiogenic stresses has been demonstrated. It has been shown that treatment … The effectiveness of the use of citrus pectin fermentolysis products to stimulate the manifestations of phytoimmunity and resistance to abiogenic stresses has been demonstrated. It has been shown that treatment with oligosaccharides of deesterified citrus pectin (polygalacturonic acid, PGA) induces the synthesis of lignin and an increase in the content of phenolic acids in the cell walls of cucumber hypocotyls (Cucumis sativus). It was found that modification of PGK by glucosamine residues increases the activity of its fermentolysis products and leads to a 10% increase in the total content of phenolic compounds in the cell walls of cucumber hypocotyls compared with the results of processing plants with fragments of unmodified PGK. At the same time, the absolute content of the dominant phenolic components – caffeic and p-coumaric acids increases by 55% and 27%, respectively, and the spectrum of minor components of phenolic acids in the cell wall of etiolated cucumber hypocotyls also changes. The modification variant proposed in the work allows to obtain polysaccharides with a regulated content of the injected ligand. The condensation reaction with the formation of a chemically resistant amide bond makes it possible to effectively dope carbohydrate polysaccharides and their fragments, which increases the possibility of obtaining bioactive glycoconjugates for use as inducers of resistance to abiogenic stresses and diseases that localize infection during plant infection.

Xyloglucan endotransglucosylase/hydrolase 25 positively regulates the lead tolerance in Raphanus sativus

2025-06-13

Tong Han , Yongmei Cui , Yang Jing +6 more | Frontiers in Plant Science

Raphanus sativus , an important root vegetable native to China, is widely cultivated for its nutritional value and diverse applications. However, it is highly sensitive to lead (Pb) stress, with … Raphanus sativus , an important root vegetable native to China, is widely cultivated for its nutritional value and diverse applications. However, it is highly sensitive to lead (Pb) stress, with Pb predominantly accumulating in the roots. Previous studies have highlighted the pivotal role of xyloglucan endotransglucosylase/hydrolase (XTH) in plant responses to heavy metal stress. Despite this, a comprehensive identification, molecular characterization, and functional analysis of the XTH gene family in R. sativus has been lacking. In this study, 28 XTH genes were identified in R. sativus . Gene structure analysis revealed the presence of eight conserved motifs, along with variations in exon-intron organization and chromosomal distribution across all chromosomes. Phylogenetic analysis of XTH genes from R. sativus , Arabidopsis thaliana and Oryza sativa grouped them into five distinct clades, suggesting their evolutionary conservation and potential functional diversification. Transcriptome sequencing and qRT-PCR analysis showed that RsXTH25 was strongly induced by Pb stress. Transgenic hairy roots overexpressing RsXTH25 exhibited enhanced Pb tolerance, evidenced by reduced chlorosis, increased fresh weight, improved photosynthetic performance, and lower oxidative damage under Pb stress. Furthermore, several transcription factors, such as RsERF2, RsHD-ZIP22, and etc., exhibited strong positive correlations with RsXTH25 , implying their roles in regulating Pb-induced RsXTH25 expression. Overall, this study provides insights into the XTH gene family in R. sativus and highlights their critical roles in Pb stress response.

Anti-inflammatory and hepatoprotective effects of galactose-rich heteropolysaccharides from Laoshan green tea and its physicochemical properties

2025-06-12

Shuying Lan , Rongshen Wang , Hong Gao +7 more | Natural Product Research

The extraction conditions of Laoshan green tea extracts were optimised by response surface method. In vitro, the MDA, NO, TNF-α, and IL-6 levels were significantly inhibited and SOD level was … The extraction conditions of Laoshan green tea extracts were optimised by response surface method. In vitro, the MDA, NO, TNF-α, and IL-6 levels were significantly inhibited and SOD level was increased after Laoshan green tea polysaccharides (GTPS) administration in RAW264.7 cells induced by LPS. Besides, GTPS also suppressed NF-κB, TNF-α and IL-6 expression. In vivo, the spleen and liver organ indices, and TNF-α, IL-6, ALT and AST levels were significantly inhibited after GTPS treatment in LPS-induced mice. The liver injury was also significantly alleviated. Overall, GTPS may be therapeutic reagents to attenuate inflammation and liver injury. GTPS were acidic galactose-rich heteropolysaccharides containing sulphate groups. GTPS were composed of Man, GalN, GlcA, Glc, Gal, and Ara in molar ratios of 1.66:1.00:6.92:5.44:46.71:12.08 with the molecular weights of 81.73, 659.87, and 1304.39 kDa.

Phenethyl Alcohol-Loaded Polysaccharide Complex Films: Preparation, Characterization, and Potential for Prune Fruit Preservation

2025-06-12

Rui Tian , Xinqian Zhang , Kuanbo Cui +7 more | ACS Food Science & Technology

Optimizing mucilage extraction from Plantago major seeds using response surface methodology for enhanced functional characteristics

2025-06-12

Aamna Majeed , Sumia Akram , Gulzar Muhammad +3 more | Journal of Food Measurement & Characterization

Structural characterization and anti-tumor immunomodulatory effects of polysaccharides from Astragalus mongholicus with different cultivation modes

2025-06-12

Yun Zhang , Nan Li , Hexin Gong +7 more | International Journal of Biological Macromolecules

Optimisation of ultrasound-assisted extraction and evaluation of anti-inflammatory and antioxidant activities of polysaccharides from Livistona chinensis fructus

2025-06-12

Jiaquan Liu , Rihui Wu , Jingyu Wu +5 more | Natural Product Research

Livistona chinensis fructus, a traditional medicinal fruit from southern China, is known for its ability to promote blood circulation, alleviate stagnation, and soften masses. It has been historically applied in … Livistona chinensis fructus, a traditional medicinal fruit from southern China, is known for its ability to promote blood circulation, alleviate stagnation, and soften masses. It has been historically applied in chronic hepatitis treatment and shows emerging potential in cancer therapy. However, the key bioactive components remain unclear. This study aimed to optimise the ultrasound-assisted extraction of polysaccharides (LCP) from L. chinensis using Response Surface Methodology (RSM). Optimal extraction conditions-the liquid-to-solid ratio of 18:1 mL/g, extraction time of 2.2 h, and temperature of 88 °C-resulted in a 7.2% LCP yield with a low relative standard deviation (0.095%). In vitro assays using LPS-induced RAW 264.7 macrophages demonstrated that LCP significantly suppressed inflammatory markers (NO, IL-1β, TNF-α) and upregulated the anti-inflammatory cytokine IL-10. Moreover, LCP exhibited strong antioxidant activity, with IC50 values of 0.474 and 1.963 mg/mL against ABTS and DPPH radicals, respectively. In H2O2-induced oxidative stress models, LCP protected RAW 264.7 cells and reduced reactive oxygen species (ROS) levels in a dose-dependent manner. These results highlight the therapeutic potential of LCP as a natural anti-inflammatory and antioxidant agent, providing a scientific basis for its future development in medicinal applications.