269 CELL WALL CHANGES IN RIPENING NASH1 (HOSUI) FRUIT

Nectarine fruit (Prunus persica (L) Batsch) cv. Fantasia, were ripened immediately after harvest (normal ripening), or stored for 6 weeks either continuously at 0°C or were intermittently warmed (IW) for 48 h at 20C after 2 and 4 weeks, and then ripened. Fruit subjected to IW ripened normally, whereas the continuously stored fruit developed mealiness during ripening. Normal ripening was associated with solubilization and depolymerization of pectic polymers and a net loss of galactose. Only limited pectic solubilization and removal of side chains occurred during ripening of mealy fruit. Pectic polymer polymerization occurred at each IW occasion continued during ripening after storage, but was not as extensive as in normally ripened fruit. Mealy fruit had high autolytic capacity, probably as a result of insoluble pectic polymers in the cell wall that were not solubilized during ripening. The release of uronic acid suggests that cool storage temperatures do not irreversibly inhibit polygalacturonase activity.

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Pectin Rhamnogalacturonan II: On the “Small Stem with Four Branches” in the Primary Cell Walls of Plants

International Journal of Carbohydrate Chemistry ◽

10.1155/2011/964521 ◽

2011 ◽

Vol 2011 ◽

pp. 1-11 ◽

Cited By ~ 17

Author(s):

Beda M. Yapo

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Vascular Plants ◽

Minor Component ◽

Primary Cell ◽

Side Chains ◽

Complex Cell ◽

Rhamnogalacturonan Ii ◽

Branching Point ◽

A Chain

Rhamnogalacturonan II (RG-II) is a type of block copolymer of complex pectins that represents a quantitatively minor component of the primary cell walls of land (vascular) plants. The structural composition of RG-II is almost totally sequenced and appears to be remarkably conserved in all tracheophytes so far examined. The backbone of RG-II, released from complex (cell wall) pectins by endo-polygalacturonase (Endo-PG) treatment, has been found to contain up to 15 (1→4)-linked-α-D-GalpA units, some of which carry four well-defined side chains, often referred to as A-, B-, C-, and D-side chains. Nevertheless, the relative locations on the backbone of these four branches, especially the A chain, remain to be ascertained. A combination of different data suggests that neither the terminal nonreducing GalA nor the contiguous GalA unit is likely to be the branching point of the A chain, but probably the ninth GalA residue from the reducing end, assuming a minimum backbone length of 11 (1→4)-linked-α-d-GalpA. The latest reports on RG-II are here highlighted, with a provided update for the macrostructure and array of functionalities.

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The composition of the cell wall of Fusicoccum amygdali

Biochemical Journal ◽

10.1042/bj1250461 ◽

1971 ◽

Vol 125 (2) ◽

pp. 461-471 ◽

Cited By ~ 13

Author(s):

K. W. Buck ◽

M. A. Obaidah

Keyword(s):

Cell Wall ◽

Sodium Hydroxide ◽

Cell Walls ◽

Digestive Enzymes ◽

Helix Pomatia ◽

Water Soluble ◽

Extracellular Polysaccharides ◽

Lytic Enzymes ◽

Similar Nature ◽

Dark Blue

1. The cell wall of Fusicoccum amygdali consisted of polysaccharides (85%), protein (4–6%), lipid (5%) and phosphorus (0.1%). 2. The main carbohydrate constituent was d-glucose; smaller amounts of d-glucosamine, d-galactose, d-mannose, l-rhamnose, xylose and arabinose were also identified, and 16 common amino acids were detected. 3. Chitin, which accounted for most of the cell-wall glucosamine, was isolated in an undegraded form by an enzymic method. Chitosan was not detected, but traces of glucosamine were found in alkali-soluble and water-soluble fractions. 4. Cell walls were stained dark blue by iodine and were attacked by α-amylase, with liberation of glucose, maltose and maltotriose, indicating the existence of chains of α-(1→4)-linked glucopyranose residues. 5. Glucose and gentiobiose were liberated from cell walls by the action of an exo-β-(1→3)-glucanase, giving evidence for both β-(1→3)- and β-(1→6)-glucopyranose linkages. 6. Incubation of cell walls with Helix pomatia digestive enzymes released glucose, N-acetyl-d-glucosamine and a non-diffusible fraction, containing most of the cell-wall galactose, mannose and rhamnose. Part of this fraction was released by incubating cell walls with Pronase; acid hydrolysis yielded galactose 6-phosphate and small amounts of mannose 6-phosphate and glucose 6-phosphate as well as other materials. Extracellular polysaccharides of a similar nature were isolated and may be formed by the action of lytic enzymes on the cell wall. 7. About 30% of the cell wall was resistant to the action of the H. pomatia digestive enzymes; the resistant fraction was shown to be a predominantly α-(1→3)-glucan. 8. Fractionation of the cell-wall complex with 1m-sodium hydroxide gave three principal glucan fractions: fraction BB had [α]D +236° (in 1m-sodium hydroxide) and showed two components on sedimentation analysis; fraction AA2 had [α]D −71° (in 1m-sodium hydroxide) and contained predominantly β-linkages; fraction AA1 had [α]D +40° (in 1m-sodium hydroxide) and may contain both α- and β-linkages.

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Polysaccharide compositions of collenchyma cell walls from celery (Apium graveolens L.) petioles

10.26686/wgtn.12597761.v1 ◽

2020 ◽

Author(s):

D Chen ◽

PJ Harris ◽

Ian Sims ◽

Z Zujovic ◽

LD Melton

Keyword(s):

Cell Wall ◽

Nmr Spectroscopy ◽

Cell Walls ◽

Soluble Fraction ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Water Soluble ◽

Magic Angle ◽

Methyl Esterification ◽

Angle Spinning

© The Author(s). 2017. Background: Collenchyma serves as a mechanical support tissue for many herbaceous plants. Previous work based on solid-state NMR and immunomicroscopy suggested collenchyma cell walls (CWs) may have similar polysaccharide compositions to those commonly found in eudicotyledon parenchyma walls, but no detailed chemical analysis was available. In this study, compositions and structures of cell wall polysaccharides of peripheral collenchyma from celery petioles were investigated. Results: This is the first detailed investigation of the cell wall composition of collenchyma from any plant. Celery petioles were found to elongate throughout their length during early growth, but as they matured elongation was increasingly confined to the upper region, until elongation ceased. Mature, fully elongated, petioles were divided into three equal segments, upper, middle and lower, and peripheral collenchyma strands isolated from each. Cell walls (CWs) were prepared from the strands, which also yielded a HEPES buffer soluble fraction. The CWs were sequentially extracted with CDTA, Na2CO3, 1 M KOH and 4 M KOH. Monosaccharide compositions of the CWs showed that pectin was the most abundant polysaccharide [with homogalacturonan (HG) more abundant than rhamnogalacturonan I (RG-I) and rhamnogalacturonan II (RG-II)], followed by cellulose, and other polysaccharides, mainly xyloglucans, with smaller amounts of heteroxylans and heteromannans. CWs from different segments had similar compositions, but those from the upper segments had slightly more pectin than those from the lower two segments. Further, the pectin in the CWs of the upper segment had a higher degree of methyl esterification than the other segments. In addition to the anticipated water-soluble pectins, the HEPES-soluble fractions surprisingly contained large amounts of heteroxylans. The CDTA and Na2CO3 fractions were rich in HG and RG-I, the 1 M KOH fraction had abundant heteroxylans, the 4 M KOH fraction was rich in xyloglucan and heteromannans, and cellulose was predominant in the final residue. The structures of the xyloglucans, heteroxylans and heteromannans were deduced from the linkage analysis and were similar to those present in most eudicotyledon parenchyma CWs. Cross polarization with magic angle spinning (CP/MAS) NMR spectroscopy showed no apparent difference in the rigid and semi-rigid polysaccharides in the CWs of the three segments. Single-pulse excitation with magic-angle spinning (SPE/MAS) NMR spectroscopy, which detects highly mobile polysaccharides, showed the presence of arabinan, the detailed structure of which varied among the cell walls from the three segments. Conclusions: Celery collenchyma CWs have similar polysaccharide compositions to most eudicotyledon parenchyma CWs. However, celery collenchyma CWs have much higher XG content than celery parenchyma CWs. The degree of methyl esterification of pectin and the structures of the arabinan side chains of RG-I show some variation in the collenchyma CWs from the different segments. Unexpectedly, the HEPES-soluble fraction contained a large amount of heteroxylans.

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Studies of the structure and chemical composition of the cell walls of Vaucheriaceae and Saprolegniaceae

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1963.0056 ◽

1963 ◽

Vol 158 (973) ◽

pp. 435-445 ◽

Cited By ~ 35

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Insoluble Fraction ◽

Water Soluble ◽

Hot Water ◽

Cellulose Microfibrils ◽

Wall Material ◽

Native Cellulose ◽

A Cell ◽

Crystalline Component

The cell walls of members of the Vaucheriaceae and Saprolegniaceae have been examined by X-ray analysis and electron microscopy, and their composition determined by hydrolysis and paper partition chromatography of the hydrolysates. Both differences and similarities between the members of these two species examined are found to supplement the comparative morphological and physiological information at present available. Saprolegnia , Achlya , Brevilegnia and Dictyuchus among the Saprolegniaceae possess hot-water soluble polysaccharides containing glucose residues only. This polysaccharide is not crystallographically identical with the polysaccharide found in Vaucheria sessilis with a similar solubility. The members of the Saprolegniaceae contain large amounts of alkali-soluble polysaccharides in contrast with the negligible amount found in V. sessilis . These polysaccharides are only weakly crystalline, but the indications are that the same polysaccharides may occur throughout the Saprolegniaceae. The alkali-insoluble wall material of Vaucheria species consists of highly crystalline native cellulose with large, apparently randomly arranged, microfibrils. The hydrolysate of this material contains ribose, xylose and arabinose in addition to glucose, presumably representing strongly bound pentosans. Native cellulose also occurs in the Saprolegniaceae but only in small proportion. The bulk of the alkali-insoluble fraction in the walls of these fungi appears amorphous in the electron microscope and is only weakly crystalline. It consists of one or m ore substances containing glucose, mannose, ribose and possibly other sugars together with traces of glucosamine. These substances presumably cover the cellulose microfibrils. The total quantity of non-cellulosic polysaccharide in the Saprolegniaceae approaches 85% of the total wall weight in contrast with the situation in Vaucheria where the cellulose alone approaches 90% of the total cell wall. Dichotomosiphon is unique among the organism s studied in this paper, in possessing a cell wall entirely soluble in alkali and composed of approximately equal quantities of glucose and xylose. The crystalline component is aβ-1,3-linked xylan, as already reported for some of the Siphonales (closely related algae) by Frei & Preston.

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Molecular Weight and Degree of Methoxylation in Cell Wall Polyuronide during Softening in Pear and Apple Fruit

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.117.4.600 ◽

1992 ◽

Vol 117 (4) ◽

pp. 600-606 ◽

Cited By ~ 52

Author(s):

H. Yoshioka ◽

K. Aoba ◽

Y. Kashimura

Keyword(s):

Molecular Weight ◽

Cell Wall ◽

Cell Walls ◽

Soluble Fraction ◽

Apple Fruit ◽

Water Soluble ◽

Pear Fruit ◽

Water Soluble Fraction ◽

High Degree ◽

Soluble Fractions

The concentrations of water-soluble polyuronides in apples [Malus domestica Borkh.) and pears (Pyrus communis L.) increased, but those of EDTA- and HCl-soluble polyuronides decreased during softening. Total polyuronide content decreased slightly during softening in both fruits. Depolymerization of polyuronides was observed only in the water-soluble fraction in pear fruit during softening, concomitant with an increase in polygalacturonase (PG) activity. No detectable depolymerization was observed in any of the polyuronide fractions during softening of apple fruit nor was any PG activity detected. The polyuronide fractions extracted from pear and apple cell walls contained various amounts of methoxyl groups. Polyuronides with a high degree of methoxylation were preferentially lost from EDTA- and HCl-soluble polyuronides during softening of both fruit. The water-soluble polyuronide had a lower degree of methoxylation than those lost in the EDTA- and HCl-soluble fractions. These results suggest de-esterification of polyuronides with a high degree of methoxylation rather than the depolymerization of polyuronides in the solubilization of polyuronides during ripening of apples and pears.

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Methanol, pectin and pectinesterase changes during soybean seed maturation

Seed Science Research ◽

10.1017/s096025859900032x ◽

1999 ◽

Vol 9 (4) ◽

pp. 311-320 ◽

Cited By ~ 9

Author(s):

James L. Koch ◽

Marcin Horbowicz ◽

Ralph L. Obendorf

Keyword(s):

Cell Wall ◽

Uronic Acid ◽

Soybean Seed ◽

Fold Increase ◽

Sole Source ◽

Neutral Sugar ◽

In Planta ◽

Cell Wall Polysaccharides ◽

Green Color ◽

Methyl Esterification

AbstractMethanol accumulates in maturing seeds, correlating with preharvest deterioration. Since the source of methanol may be from pectin de-methylation, methanol, cell wall uronic acid, pectin methyl esterification, pectinesterase (PE; EC 3.1.1.11) activity, and neutral sugar composition and partitioning of cell wall polysaccharides were determined during soybean (Glycine max[L.] Merrill) seed development, maturation, and desiccationin planta. Axis cell wall polysaccharides were more easily solubilized, richer in uronic acid, rhamnose, and xylose, and less rich in galactose than cotyledon cell wall polysaccharides. Methanol accumulated to 9.7 μg per two cotyledons and 0.5 μg per axis; total methanol decreased to 3 μg per two cotyledons during loss of green color. Total uronic acid increased from 0.12 to 0.27 mg per axis and 0.9 to 4 mg per cotyledon between 24 and 50 days after flowering (DAF). After loss of green color, pectin methyl esterification in axes increased from 7 to 24 mole% between 50 and 60 DAF but decreased to 14 mole%by 62 DAF in latter stages of seed desiccation. In cotyledons, methyl esterification ranged from 25 to 40 mole% and was 31 mole% after desiccation. PE activity increased 100 fold in axes, including a 30-fold increase in activity after loss of green color at 46 DAF. Cotyledon PE activity was 40-fold higher than in axes at 24 DAF, declined 75% by 56 DAF, and then increased 5 fold during desiccation. Pectin methyl de-esterification by PE is sufficient to be the sole source for methanol accumulation in seed tissues during development and maturation.

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Copper and cobalt alter the cell wall composition of Cunninghamella blakesleeana

Canadian Journal of Microbiology ◽

10.1139/m86-122 ◽

1986 ◽

Vol 32 (8) ◽

pp. 654-662 ◽

Cited By ~ 18

Author(s):

G. Venkateswerlu ◽

G. Stotzky

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Control Cell ◽

Neutral Sugar ◽

Blue Color ◽

Cunninghamella Blakesleeana ◽

Highly Sensitive ◽

Phosphorous Content ◽

Chitin And Chitosan ◽

And Control

Cunninghamella blakesleeana was highly sensitive to Cu and Co on a medium containing NaNO3 as the sole nitrogen source. The nitrate reductive pathway was altered by Cu and Co, and [Formula: see text] accumulated in the medium. Under conditions of Cu toxicity, the mycelium and the cell walls acquired a blue color, and most of the Cu was located in the cell walls, which differed in several aspects from cell walls derived from Co-containing or control cultures. At half-maximal growth inhibition by Cu (2.5 μg/mL or 39.3 μM) or Co (3.5 μg/mL or 59.4 μM), the mycelia contained 1.5 μg Cu or 1.0 μg Co/mg dry tissue, respectively, but the isolated cell walls contained 33.5 μg Cu or 1.8 μg Co/mg dry cell wall. The phosphorous content of mycelia from Co-containing cultures was the same as that from control cultures, whereas that of mycelia from Cu-containing cultures contained 36% less. However, the phosphorous content of the cell walls from mycelia cultured in the presence of Cu or Co was two- and three-fold higher, respectively, than that of cell walls from control cultures. The cell walls of Cu-containing cultures contained significantly less hexosamine than the control cell walls, and chitin and chitosan were present in equal quantities. The cell walls of Co-containing cultures had the same amount of hexosamine as the control cell walls, but 88% of the hexosamine was present as chitosan and bound very little Co. The control cell walls contained approximately 60% chitosan. The cell walls of Cu-containing cultures also contained less alkali-soluble neutral sugar, but more protein, than did the walls from the control or Co-containing cultures. Only the protein of the cell walls of Cu-containing cultures contained hydroxyproline, which is usually absent in the cell walls of fungi and may have been involved in the binding of Cu and in the acquisition of the blue color. The protein of the cell walls from Co-containing cultures was abnormally high in citrulline. Chitinase not only had a greater affinity for the cell walls of Cu-containing cultures, but these were more easily hydrolyzed by the enzyme than the cell walls from Co-containing and control cultures. Melanin was not responsible for the differential rates of hydrolysis by chitinase. The cell walls from control cultures bound more DNA than did the walls from Cu- and Co-containing cultures.

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Pectin Cross-Linking Dynamics and Wall Softening during Fruit Ripening

10.32747/2002.7585197.bard ◽

2002 ◽

Author(s):

Nicholas C. Carpita ◽

Ruth Ben-Arie ◽

Amnon Lers

Keyword(s):

Gene Expression ◽

Cell Wall ◽

Cell Separation ◽

Cell Walls ◽

Methyl Esters ◽

Cross Linking ◽

Neutral Sugar ◽

Fruit Softening ◽

Methyl Esterification ◽

Softening Process

Our study was designed to elucidate the chemical determinants of pectin cross-linking in developing fruits of apple and peach and to evaluate the role of breakage cross-linkages in swelling, softening, and cell separation during the ripening. Peaches cell walls soften and swell considerably during the ripening, whereas apples fruit cells maintain wall firmness but cells separate during late stages of ripening. We used a "double-reduction" technique to show that levels of non-methyl esters of polyuronic acid molecules were constant during the development and ripening and decreased only in overripe fruit. In peach, methyl and non-methyl esters increased during the development and decreased markedly during the ripening. Non-methyl ester linkages in both fruit decreased accompanied fruit softening. The identity of the second component of the linkage and its definitive role in the fruit softening remain elusive. In preliminary examination of isolated apples cell walls, we found that phenolic compounds accumulate early in wall development but decrease markedly during ripening. Quantitative texture analysis was used to correlate with changes to wall chemistry from the fresh-picked ripe stage to the stage during storage when the cell separation occurs. Cell wall composition is similar in all cultivars, with arabinose as the principal neutral sugar. Extensive de-branching of these highly branched arabinans pre-stages softening and cell-cell separation during over-ripening of apple. The longer 5-arabinans remain attached to the major pectic polymer rhamnogalacturonan I (RG I) backbone. The degree of RG I branching, as judged from the ratios of 2-Rha:2,4-Rha, also decreases, specially after an extensive arabinan de-branching. Loss of the 4-Rham linkages correlated strongly with the softening of the fruit. Loss of the monomer or polymer linked to the RG I produce directly or indirectly the softening of the fruit. This result will help to understand the fruit softening and to have better control of the textural changes in fruit during the ripening and especially during the storage. 'Wooliness', an undesirable mealy texture that is induced during chilling of some peach cultivars, greatly reduces the fruit storage possibilities. In order to examine the hypothesis that the basis for this disorder is related to abnormality in the cell wall softening process we have carried out a comparative analysis using the resistant cultivar, Sunsnow, and a sensitive one, Hermosa. We investigated the activity of several pectin- and glycan-modifying enzymes and the expression of their genes during ripening, chilling, and subsequent shelf-life. The changes in carbohydrate status and in methyl vs. non-methyl uronate ester levels in the walls of these cultivars were examined as well to provide a basis for comparison of the relevant gene expression that may impact appearance of the wooly character. The activities of the specific polygalacturonase (PGase) and a CMC-cellulase activities are significantly elevated in walls of peaches that have become wooly. Cellulase activities correlated well with increased level of the transcript, but differential expression of PGase did not correspond with the observed pattern of mRNA accumulation. When expression of ethylene biosynthesis related genes was followed no significant differences in ACC synthase gene expression was observed in the wooly fruit while the normal activation of the ACC oxidase was partially repressed in the Hermosa wooly fruits. Normal ripening-related loss of the uronic acid-rich polymers was stalled in the wooly Hermosa inconsistent with the observed elevation in a specific PGase activity but consistent with PG gene expression. In general, analysis of the level of total esterification, degree of methyl esterification and level of non-methyl esters did not reveal any major alterations between the different fruit varieties or between normal and abnormal ripening. Some decrease in the level of uronic acids methyl esterification was observed for both Hermosa and Sunsnow undergoing ripening following storage at low temperature but not in fruits ripening after harvest. Our results support a role for imbalanced cell wall degradation as a basis for the chilling disorder. While these results do not support a role for the imbalance between PG and pectin methyl esterase (PME) activities as the basis for the disorder they suggest a possible role for imbalance between cellulose and other cell wall polymer degradation during the softening process.

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Polysaccharide compositions of collenchyma cell walls from celery (Apium graveolens L.) petioles

10.26686/wgtn.12597761 ◽

2020 ◽

Author(s):

D Chen ◽

PJ Harris ◽

Ian Sims ◽

Z Zujovic ◽

LD Melton

Keyword(s):

Cell Wall ◽

Nmr Spectroscopy ◽

Cell Walls ◽

Soluble Fraction ◽

Magic Angle Spinning ◽

Mas Nmr ◽

Water Soluble ◽

Magic Angle ◽

Methyl Esterification ◽

Angle Spinning

© The Author(s). 2017. Background: Collenchyma serves as a mechanical support tissue for many herbaceous plants. Previous work based on solid-state NMR and immunomicroscopy suggested collenchyma cell walls (CWs) may have similar polysaccharide compositions to those commonly found in eudicotyledon parenchyma walls, but no detailed chemical analysis was available. In this study, compositions and structures of cell wall polysaccharides of peripheral collenchyma from celery petioles were investigated. Results: This is the first detailed investigation of the cell wall composition of collenchyma from any plant. Celery petioles were found to elongate throughout their length during early growth, but as they matured elongation was increasingly confined to the upper region, until elongation ceased. Mature, fully elongated, petioles were divided into three equal segments, upper, middle and lower, and peripheral collenchyma strands isolated from each. Cell walls (CWs) were prepared from the strands, which also yielded a HEPES buffer soluble fraction. The CWs were sequentially extracted with CDTA, Na2CO3, 1 M KOH and 4 M KOH. Monosaccharide compositions of the CWs showed that pectin was the most abundant polysaccharide [with homogalacturonan (HG) more abundant than rhamnogalacturonan I (RG-I) and rhamnogalacturonan II (RG-II)], followed by cellulose, and other polysaccharides, mainly xyloglucans, with smaller amounts of heteroxylans and heteromannans. CWs from different segments had similar compositions, but those from the upper segments had slightly more pectin than those from the lower two segments. Further, the pectin in the CWs of the upper segment had a higher degree of methyl esterification than the other segments. In addition to the anticipated water-soluble pectins, the HEPES-soluble fractions surprisingly contained large amounts of heteroxylans. The CDTA and Na2CO3 fractions were rich in HG and RG-I, the 1 M KOH fraction had abundant heteroxylans, the 4 M KOH fraction was rich in xyloglucan and heteromannans, and cellulose was predominant in the final residue. The structures of the xyloglucans, heteroxylans and heteromannans were deduced from the linkage analysis and were similar to those present in most eudicotyledon parenchyma CWs. Cross polarization with magic angle spinning (CP/MAS) NMR spectroscopy showed no apparent difference in the rigid and semi-rigid polysaccharides in the CWs of the three segments. Single-pulse excitation with magic-angle spinning (SPE/MAS) NMR spectroscopy, which detects highly mobile polysaccharides, showed the presence of arabinan, the detailed structure of which varied among the cell walls from the three segments. Conclusions: Celery collenchyma CWs have similar polysaccharide compositions to most eudicotyledon parenchyma CWs. However, celery collenchyma CWs have much higher XG content than celery parenchyma CWs. The degree of methyl esterification of pectin and the structures of the arabinan side chains of RG-I show some variation in the collenchyma CWs from the different segments. Unexpectedly, the HEPES-soluble fraction contained a large amount of heteroxylans.

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