Altered matrix polysaccharides in cell walls of pocket galls formed by an aphid on Distylium racemosum leaves

The present work reports the results of a study on the isolation and characterization of matrix polysaccharides in the cell walls of galls formed by an aphid (Neothoracaphis yanonis) on Distylium racemosum leaves. Cell walls were isolated from both healthy Distylium leaf and gall tissues and then extracted sequentially with cyclohexane‐trans‐1,2‐diaminetetra‐acetate (CDTA), Na₂CO₃, 1 m KOH, and 4 m KOH. The amount of pectin solubilized from gall cell walls was approximately 2.6‐fold higher than the pectin solubilized from leaf cell walls, whereas the amount of hemicellulose solubilized from gall cell walls was 1.4‐fold higher than that from normal leaf cell walls. When the polysaccharides were fractionated by anion‐exchange chromatography, considerable increases in arabinose and galactose were observed in CDTA‐soluble pectic polymer (fraction PI‐1) from gall cell walls, whereas the gall cell walls had less xylose in 1 m KOH‐soluble hemicellulosic polymers (fractions HI‐2, HI‐3, and HI‐4) than did the cell walls from the healthy leaf. The hemicellulosic polymers of the gall cell walls exhibited distinctly different patterns of molecular mass, compared with the healthy leaf cell walls. These results suggest that an extensive change occurs in the matrix polysaccharide structure of the cell walls of Distylium galls formed by an aphid. In addition, many glycosylhydrolase activities were detected in the protein fraction solubilized with strong saline solution from the gall cell walls, and the activities of β‐galactosidase, β‐xylosidase and α‐l ‐arabinofuranosidase were considerably increased under gall formation.     

Structure and chemical composition of endodermal and rhizodermal/hypodermal walls of several species

CWM, isolated cell wall material
ECW, isolated endodermal cell walls
G, guaiacyl monomer
H, p-hydroxyphenyl monomer
HCW, isolated hypodermal cell walls
RHCW, isolated rhizodermal and hypodermal cell walls
S, syringyl monomer
XV, isolated xylem vessels

Endodermal cell walls of the three dicotyledoneous species Pisum sativum L., Cicer arietinum L. and Ricinus communis L. were isolated enzymatically and analysed for the occurrence of the biopolymers lignin and suberin. From P. sativum, endodermal cell walls in their primary state of development (Casparian strips) were isolated. Related to the dry weight, these isolates contained equal amounts of suberin (2·5%) and lignin (2·7%). In contrast, the endodermal cell walls of C. arietinum and R. communis, which were nearly exclusively in their secondary state of development, contained significantly higher proportions of suberin (10–20%) and only traces of lignin (1–2%). The results of the chemical analyses were supported by a microscopic investigation of Sudan III-stained root cross-sections, showing a Casparian strip restricted to the radial walls of the endodermis of P. sativum and well-pronounced red suberin lamellae in C. arietinum and R. communis roots. Compared with recently investigated monocotyledoneous species, higher amounts of suberin by one order of magnitude were detected with the secondary state of development of dicotyledoneous species. Furthermore, the carbohydrate and protein contents of primary (Clivia miniata Reg. and Monstera deliciosa Liebm.), secondary (C. arietinum and R. communis) and tertiary endodermal cell walls (Allium cepa L. and Iris germanica L.) were determined. The relative carbohydrate content of secondary endodermal cell walls was low (14–20%) compared with the content of primary (42–50%) and tertiary endodermal cell walls (60%), whereas the protein content of isolated endodermal cell walls was high in primary (13%) and secondary (8%) and low in tertiary endodermal cell walls (0·9–2%). The results presented here indicate that the quantitative chemical composition of primary, secondary, and tertiary endodermal cell walls varies significantly. Finally, cell wall proteins are described as an additional important constituent of endodermal cell walls, with the highest concentrations occurring in primary (Casparian strips) and secondary endodermal cell walls.     

Binding of metals by cell walls of Cunninghamella blakesleeana grown in the presence of copper or cobalt

Summary The binding of metals by cell walls isolated from Cunninghamella blakesleeana grown in the presence of inhibitory concentration of Cu or Co and which had altered chemical compositions was compared with the binding by control cell walls. The Co-cell walls, which had higher contents of phosphate and chitosan, bound more Cu and Co. Although the V _max for Cu and Co differed with each of the cell walls, the K _m values for the binding of Cu (6.3x10^-3 M) and Co (2.1x10^-3 M) were the same for all three types of cell walls. The cell walls also differed in their quantitative binding of various metals; control cell walls: Zn> Fe> Mn> Cd> Ca> Ni> Cu> Ag> Co> Mg; Cu-cellwalls: Zn> Fe> Mn> Cu> Ni> Cd> Ag> Ca> Co> Mg; and Co-cell walls: Fe> Zn> Cu> Mn> Cd> Ag> Ca> Ni=Co> Mg. The binding of Cu was temperature-dependent and had an optimum pH. The binding of Co was inhibited by Cu, but the binding of Cu was not inhibited by Co, and Cd totally suppressed the binding of Co but not of Cu, suggesting two binding sites on the cell walls, one exclusively for Cu and the other common to both metals but with a higher affinity for Co. The cell walls did not bind Mg. The Cu-or Co-loaded cell walls eluted with 5 mM ethylenediaminetetraacetate (EDTA) rebound these metals to the same or greater extent as the original walls, but walls eluted with 0.5 N HCl bound only 50% of that bound originally.     

Preinfection cell wall formation in roots and developing nodules ofAlnus rubra Bong

Summary The establishment of actinorhizal root nodules involves penetration of host cell walls and intracellular colonization by the nitrogen-fixing endosymbiont,Frankia (Actinomycetales). In the early stages of the infection process inAlnus, unusual cell walls with undulate profiles were observed in root tip meristematic derivatives, and in early (preinfection) derivatives of the nodule lobe meristem, inFrankia-inoculated plants. The irregular cell walls attached obliquely to preexisting walls, but were not discontinuous. Serial sections revealed that the unusual walls divided two daughter cells. Microtubules in bundled arrays were abundant near the undulate walls, and radiated in several planes. In the root tips, the anomalous cell walls were observed within one day of inoculation withFrankia.     

Dehydrodimers of Caffeic Acid in the Cell Walls of Suspension-Cultured Mentha

Dehydrodicaffeic acid derivatives were found in the cell walls of suspension-cultured cells of Mentha. Using gas chromatography/mass spectrometry (GC-MS) in a single ion chromatography at m/z 790 and m/z 718, eleven peaks of trimethylsilylated dehydrodimers of caffeic acid were detected in the extracts from the cell walls of suspension-cultured cells of Mentha using sodium hydroxide. The result suggests that dehydrodicaffeates are formed in the cell walls from two molecules of caffeate, probably formed through C-C, and C-O-C coupling processes.     

Studies on Cell Wall of Alkalophilic Bacillus

Cell walls of alkalophilic Bacillus No. C-125 and No. A-59 which grew in different pH conditions were prepared and analyzed. In the walls from cells grown at pH 10.3 (pH 10.3-cell wall) and the walls from cells grown at pH 7.5 (pH 7.5-cell wall) of the alkalophilic bacilli, the contents of neutral sugar and phosphorus were low as compared with those of Bacillus subtilis 6160, while uronic acid and amino acids were abundant. The uronic acid content of the pH 10.3-cell walls was higher than that of the pH 7.5-cell walls in both strains. The insoluble fraction (peptidoglycan) of cell walls of Bacillus No. C-125 consisted of muramic acid, glutamic acid, alanine, diaminopimelic acid and glucosamine as in neutrophilic bacilli. In the TCA soluble fraction of pH 10.3-cell walls of Bacillus No. C-125, uronic acid was a polymer of glucuronic acid containing a small amount of hexosamine, and 2/3 of the ninhydrin positive material was glutamic acid which was derived mainly from poly γ-L-glutamic acid.     

Immunocytochemical detection of lignin-related epitopes in cell walls in bryophytes and the charalean alga Nitella

Lignins are complex phenolic heteropolymers present in xylem and sclerenchyma cell walls in tracheophytes. The occurrence of lignin-like polymers in bryophytes is controversial. In this study two polyclonal antibodies against homoguaiacyl (G) and guaiacyl/syringyl (GS) synthetic lignin-like polymers that selectively labelled lignified cell walls in tracheophytes also bound to cell walls in bryophytes, the GS antibody usually giving a stronger labelling than the G antibody. In contrast to tracheophytes, the antibody binding in liverworts and mosses was not tissue-specific. In the hornworts Megaceros flagellaris and M. fuegiensis the pseudoelaters and spores were labelled more intensely than the other cell types with the GS antibody. The cell walls in Nitella were labelled with both antibodies but no binding was observed in Coleochaete. The results suggest that the ability to incorporate G or GS moieties in cell walls is a plesiomorphy (primitive character) of the land plant clade.     

Comparative investigation of primary and tertiary endodermal cell walls isolated from the roots of five monocotyledoneous species: chemical composition in relation to fine structure

The chemical composition of isolated endodermal cell walls from the roots of the five monocotyledoneous species Monstera deliciosa Liebm., Iris germanica L., Allium cepa L., Aspidistra elatior Bl. and Agapanthus africanus (L.) Hoffmgg. was determined. Endodermal cell walls isolated from aerial roots of M. deliciosa were in their primary developmental state (Casparian bands). They contained large amounts of lignin (6.5% w/w) and only traces of suberin (0.5% w/w). Endodermal cell walls isolated from the other four species were in their tertiary developmental state. Lignin was still the more abundant cell wall polymer with amounts ranging from 3.8% (w/w, A. cepa) to 4.5% (w/w, I. germanica). However, compared to endodermal cell walls in their primary state of development (Casparian bands), tertiary endodermal cell walls contained significantly higher amounts of suberin, ranging from 1.8% (w/w, I. germanica) to 3.0% (w/w, A. africanus). Thus, chemical characterization of endodermal cell walls from five different species revealed that lignin was the dominant cell wall polymer in the Casparian band of M. deliciosa, whereas tertiary endodermal cell walls contained, in addition to lignin, increasing amounts of suberin (I. germanica, A. cepa, A. elatior and A. africanus). Besides the two biopolymers lignin and suberin, cell wall carbohydrates in the range of between 40 and 60% were also quantified. The sum of all cell wall compounds investigated by gas chromatography resulted in a recovery of 50–80% of the dry weight of the isolated cell wall material. Quantitative chromatographic results in combination with microscopic studies are consistent with the existence of a distinct suberin lamella and lignified tertiary wall deposits. From these data it can be concluded that the barrier properties of the endodermis towards the apoplastic transport of ions and water will increase from primary to tertiary endodermal cell walls due to their increasing amounts of suberin. Received: 23 August 1997 / Accepted: 28 January 1998     

Morphology and taxonomy of Oscillatoria redekei (Cyanophyta)

The polymorphous trichome apices of Oscillatoria redekei are described with respect to their shape and size. Breakage of trichomes may occur either trans- or intercellularly. The development and localization of intercellular trichome breakage were observed. Transmission electron microscopy shows that the fine structure of cell walls resembles that of Pseudanabaena galeata. Longitudinal walls consist of three or four layers and lack a sheath, while the cross walls are composed of three layers with a dominating L₂-layer. In contrast to P. galeata, the centroplasm and most of the thylakoidal region of adjacent cells of O. redekei are connected by the cross walls forming obtuse angles at the site of the longitudinal walls. The main characteristics of O. redekei and of Pseudanabaena species are discussed.     

DISTRIBUTION,MORPHOLOGICAL DIVERSITY AND EVIDENCE FOR POLYPLOIDY IN NORTH AMERICAN ZYGNEMATACEAE (CHLOROPHYTA)1

Large-scale collections of Zygnemataceae in the continental United States of America were made between March and August in 1982, 1983, and 1984. Collections were made on a 31000-km transect through 35 states. Zygnemataceae were found at 318 sites was inspected. Temperature average 19°C and p^H averaged 6.1 over all sites. Algal strains in collections were identified to genus, characterized for filament width, chloroplast number, and end wall type, then photographed and isolated into unialgal culture. Spirogyra was the most common genus collected(632 strains), followed in abundance by Zygnema (174 Strains) and Mougeotia (135 strains). These three genera contained 95% of the strains collected and were equally widely distributed. Strains of the three genera frequently occurred together; no genus displayed evidence of habitat specialization among the three habitat types: flowing water, permanent ponds or lakes, and temporary pools. In Spirogyra, strains with plane (flat) end walls were four times more abundant than those with replicate (interlocking) end walls. Spirogyra with plane end walls showed more variation in filament width than Zygnema, Mougeotia, or Spirogyra with replicate end walls. In Spirogyra with plane end walls, filament width was correlted with nuclear DNA content and number of strains found per collection site was twice that of other genera or Spirogyra, with replicate end walls. Spirogyra strains wider than 70 μm were more frequent on the northern part of the transect. It is proposed that polyploidy may be of widespread occurrence in Spirogyra with plane end walls and that associated morphological plasticity may account for the high apparent specied diversity and survival of the genus in a wider variety of microhabitats than occupied by other Zygnemataceae.     

Modifications of Cortical Cell Walls in Roots of Seedless Vascular Plants

Forty-three species of seedless vascular plants were assessed for modifications to root cortical cell walls. All species except Lycopodium had an endodermis with distinct Casparian bands. Experiments with the apoplastic tracer berberine hemisulfate showed that walls of all root cortical cells in the two Lycopodium species tested were permeable to this tracer. Although most species examined lacked a hypodermis several Equisetum species had a hypodermis with modified walls. Three Selaginella species had distinct Casparian bands in this cortical cell layer. This layer, therefore, is an exodermis in Selaginella and its presence limited the inward diffusion of the apoplastic tracer berberine hemisulfate.     

Fine Structure of Five Species of Myxomycetes with Clustered Spores*

SYNOPSIS. Electronmicroscopic studies were made of 5 species of Myxomycetes with clustered spores to determine the exact mechanism holding the spores together. In Dianema corticatum the neighboring spore walls were closely appressed and appeared to be fused at numerous points. In Trichia synsporum there was a substance between the outer spore walls of adjacent spores which seemed to cement them together. In Badhamia nitens the spore walls were completely fused along their closely appressed surfaces. The adjacent spores of Badhamia versicolor appeared to be free, or if any fusion point was present it was only at the tips of the ornamentation. In Physarum bogoriense such tips were in contact with those of neighboring spores and were occasionally fused at these points.     

Attempted localization of a substrate for chitinases in plant cells reveals abundant N-acetyl-d-glucosamine residues in secondary walls

Ultrathin sections of healthy and fungus-infected plant tissue were treated with either wheat-germ agglutinin (WGA) ovomucoid-gold complex or microbial chitinase-gold complexes for localizing putative chitin-like macromolecules. Fungal cell walls, known to contain chitin, were labeled with both probes and were considered as positive controls. Plant secondary cell walls of both healthy and infected tissues were also intensely labeled whereas compound middle lamella-primary walls and cell cytoplasm were free of labeling. Enzymatic digestion of plant tissues with chitinase from Streptomyces griseus abolished the fungal cell wall labeling but did not interfere with that of plant secondary cell walls. This suggests that polymers analogous to fungal chitin are absent in plant cell walls. Tissue digestions with either proteinase K or lipase led to surprising results as far as the possible nature of N-acetylglucosamine-containing molecules is concerned. The loss of labeling over plant secondary walls following lipase digestion suggests that N-acetylglucosamine residues may be linked to lipids to form glycolipids. However, these results have to be viewed with caution since the possibility that peptides may be present but inacessible to proteinase K should be considered. The role of the detected N-acetylglucosamine containing molecules as possible substrates for plant chitinases is discussed.     

Mitogenic Activity of the Cell Walls of Mycobacteria,Nocardia, Corynebacteria and Anaerobic Coryneforms

The mitogenic activity of the cell walls prepared from Mycobacterium bovis BCG, Nocardia rubra, Corynebacterium diphtheriae PW8, and four species of Propionibacterium, Corynebacterium parvum ATCC 11829, Propionibacterium acnes C7, Propionibacterium granulosum ATCC 25564 and Propionibacterium avidum ATCC 25577, were investigated. These cell walls were active as mitogens on normal spleen cells, anti-θ sera-treated spleen cells, macrophage-depleted spleen cells of C57BL/6J mice and cortisone-treated thymocytes of C57BL/6J mice. It was also shown that these cell walls were mitogenic on spleen cells and macrophage-depleted spleen cells of congenitally athymic (nude) mice. The above results suggest that the cell walls investigated in this study act as mitogens on both thymus-derived lymphocytes (T-cells) and bone marrow-derived lymphocytes (B-cells).     

On the cell wall composition of the apiculate yeasts

Summary Sonic oscillation was used for the purpose of obtaining clean, chemically intact cell walls. The rate of disruption was determined for cells ofHanseniaspora uvarum andSaccharomyces cerevisiae. The carbohydrate fractions of cell walls ofHanseniaspora uvarum, H. valbyensis, Kloeckera apiculata, Saccharomycodes ludwigii andSaccharmyces cerevisiae were shown to be similar. Chromatography of cell wall hydrolysates of all these species demonstrated that glucose and mannose were the only sugars present (in about equal amounts) besides traces of glucosamine. The cell walls ofH. uvarum contained 78.1 per cent carbohydrates, 7 per cent protein and approximately 0.05 per cent of chitin. Fractionation of the polysaccharides lead to a recovery of 83.3 per cent of the carbohydrates present (30.4 per cent glucan and 34.9 per cent mannan). Saccharomyces cerevisiae cell walls were found to have a carbohydrate content of 82.8 per cent, 6.5 per cent protein and a trace of chitin (0.04 per cent). Nadsonia elongata contained a relatively large amount of chitin (ca. 5 per cent) and lacked mannan in its cell walls. It was concluded thatHanseniaspora andSaccharomycodes are closely related to theSaccharomyceteae but they have little in common with species ofNadsonia.     

Hyphal walls of isolated lichen fungi

The hyphal walls of three mycobionts, isolated from the lichens Xanthoria parietina, Tornabenia intricata and Sarcogyne sp. were investigated by two techniques: microautoradiography of fungal colonies exposed to radioactive carbohydrate precursors; and binding, in vivo, of fluorescein conjugated lectins to hyphal walls of such colonies.N-[³H] acetylglucosamine was readily incorporated into tips, young hyphal walls and septa of the three mycobionts and the free-living fungus Trichoderma viride, but not into Phytophthora citrophthora, indicating that chitin is a major component of the mycobionts' hyphal walls. All three mycobionts, but neither of the free-living fungi, incorporated [³H] mannose and [³H] mannitol into their hyphal walls.Fluorescein-conjugated wheat germ agglutinin was bound to the hyphal walls of the three mycobionts and T. viride, but not to the walls of P. citrophthora; the binding pattern was similar to the grain pattern obtained in autoradiographs after short N-[³H] acetylglucosamine labelling. As wheat germ agglutinin binds specifically to chitin oligomers, the lectin binding tests further confirmed that chitin is a mycobiont hyphal wall component.Binding characteristics of several fluorescein-conjugated lectins to the three mycobionts indicated that this technique can yield useful information concerning the chemical composition of hyphal wall surfaces.List of abbreviations FITC fluorescein isothiocyanate - WGA wheat germ agglutinin - TCA trichloroacetic acid - PNA peanut agglutinin - LA lotus agglutinin - Glc NAc N-acetylglucosamine - ConA concanavalin A - SBA soybean agglutinin - WBA waxbean agglutinin Part of an M.Sc. thesis submitted by A. Braun to the Department of Botany, Tel Aviv University.     

Autolytic Enzyme System of Clostridium botulinum

Isolated cell walls of Clostridium botulinum type A strain 190L released an autolysin during autolysis of the cell walls. The autolysin was isolated from the cell walls, and partially purified 18.6-fold by ammonium sulfate precipitation, chromatography on DEAE-cellulose and gel filtration through Sephadex G-100. The purified preparation of the autolysin showed 2 major and 2 minor protein bands on Polyacrylamide gel electrophoresis. Some properties of the autolysin were examined using SDS-treated cell walls of the organisms as a substrate. The autolysin was active over a pH range of 6 to 8, with a maximum near pH 6.8. The lytic activity was stimulated by 10^?4 M each of Co⁺⁺, Mg⁺⁺ and Ca⁺⁺ in the order, whereas it was inhibited markedly by Cu⁺⁺. Mercaptoethanol (10^?4–10^?3 M) significantly activated the lytic action. Trypsin and nagarse (10 μg/ml) also stimulated the lytic activity. The lytic spectrum of the autolysin toward the SDS-treated cell walls obtained from various types of C. botulinum and C. perfringens indicated a relatively high specificity. After treatment with hot formamide the cell walls of C. botulinum increased in susceptibility to the autolysin.     

Characterization of the Sclerotinia sclerotiorum cell wall proteome

We used a proteomic analysis to identify cell wall proteins released from Sclerotinia sclerotiorum hyphal and sclerotial cell walls via a trifluoromethanesulfonic acid (TFMS) digestion. Cell walls from hyphae grown in Vogel's glucose medium (a synthetic medium lacking plant materials), from hyphae grown in potato dextrose broth and from sclerotia produced on potato dextrose agar were used in the analysis. Under the conditions used, TFMS digests the glycosidic linkages in the cell walls to release intact cell wall proteins. The analysis identified 24 glycosylphosphatidylinositol (GPI)‐anchored cell wall proteins and 30 non‐GPI‐anchored cell wall proteins. We found that the cell walls contained an array of cell wall biosynthetic enzymes similar to those found in the cell walls of other fungi. When comparing the proteins in hyphal cell walls grown in potato dextrose broth with those in hyphal cell walls grown in the absence of plant material, it was found that a core group of cell wall biosynthetic proteins and some proteins associated with pathogenicity (secreted cellulases, pectin lyases, glucosidases and proteases) were expressed in both types of hyphae. The hyphae grown in potato dextrose broth contained a number of additional proteins (laccases, oxalate decarboxylase, peroxidase, polysaccharide deacetylase and several proteins unique to Sclerotinia and Botrytis) that might facilitate growth on a plant host. A comparison of the proteins in the sclerotial cell wall with the proteins in the hyphal cell wall demonstrated that sclerotia formation is not marked by a major shift in the composition of cell wall protein. We found that the S. sclerotiorum cell walls contained 11 cell wall proteins that were encoded only in Sclerotinia and Botrytis genomes.     

Ion-exchange characteristics of the cell walls isolated from the thallus of the lichen <Emphasis Type="Italic">Peltigera aphthosa</Emphasis> (L.) Willd

Ion-exchange characteristics of the cell walls isolated from different zones of the foliose lichen Peltigera aphthosa (L.) Willd were determined. Four types of ionogenic groups were revealed in the thallus cell walls of P. aphthosa, namely amino groups, carboxylic groups of uronic acids, carboxylic groups of phenolic acids, and phenolic OH groups. They may participate in the ion-exchange reactions with the ions of the environment. The amount of ionogenic groups in P. aphthosa cell walls was found to depend on the zone and age of the thallus.     

Screening for microorganism with cell wall lytic activity to produce protoplast-forming enzymes

Several different bacteria and fungi capable of degrading yeast cell walls were isolated in the course of a screening programme. One Streptomyces and one Acremonium strain were found to degrade yeast cell walls extremely well. Both isolates produced enzymes in liquid culture that could be used for protoplasting of Sporobolomyces salmonicolor (DSM 70851) and Rhodotorula rubra (DSM 70403). This fact is quite remarkable as, so far, S. salmonicolor could not be protoplasted by commercially available enzymes. Correspondence to: W. Kaul