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1.
Carbohydr Polym ; 125: 241-8, 2015 Jul 10.
Article in English | MEDLINE | ID: mdl-25857980

ABSTRACT

The native polysaccharide of cashew-nut tree gum exudate (CNTG) and its arabinogalactan-protein component (CNTG-AGP) were tested by using immuno-stimulant and anti-inflammatory in vitro assays of murine peritoneal macrophage activities. In the assay for immuno-stimulant activity (without previous treatment with lipopolysaccharide; LPS), CNTG increased the production of interleukin (IL)-10 and both CNTG and CNTG-AGP decreased the concentrations of IL6. When the macrophages were incubated in the presence of LPS and CNTG a decrease in the levels of nitric oxide (NO(·)) and IFN-γ was observed. The results could explain the popular use of CNTG as an anti-inflammatory. In addition, CNTG is the main component of the cashew-nut tree gum exudate, which has been considered a versatile polymer with potential pharmaceutical and food industry applications. These data may contribute to the study of the immunomodulation activity of plant polysaccharides, as well as encourage future experiments in the field of cashew-nut tree gum exudate applications.


Subject(s)
Anacardium/chemistry , Macrophages, Peritoneal/drug effects , Plant Gums/pharmacology , Animals , Cells, Cultured , Interferon-gamma/genetics , Interferon-gamma/metabolism , Interleukin-10/genetics , Interleukin-10/metabolism , Macrophages, Peritoneal/metabolism , Mice , Mucoproteins/chemistry , Mucoproteins/pharmacology , Nitric Oxide/metabolism , Plant Gums/chemistry , Plant Proteins/chemistry , Plant Proteins/pharmacology
2.
Carbohydr Polym ; 106: 460-8, 2014 Jun 15.
Article in English | MEDLINE | ID: mdl-24721102

ABSTRACT

The ß-D-Glc Yariv reagent is frequently used to isolate and to study the structure of arabinogalactan-proteins with the arabinogalactan type II structure. The present paper describes the aggregation features of the Yariv reagent in water, salt solutions and in organic solvents as determined by NMR, absorption spectroscopy and light scattering experiments. The results indicate that in water the Yariv reagent forms aggregates of up to 300 units and in 1% aqueous NaCl the degree of aggregation is approx. 150. The aggregates are formed both by H-bonds and hydrophobic interactions, the former appearing to be of most importance in water. The interaction between the Yariv reagent and an AGP fraction from gum arabic, showed a degree of aggregation of the Yariv reagent when using 1% NaCl to be of approx. 150 units, whereas disruption of the aggregate took place in 10% NaCl with an aggregation number of approx. 100. Partial acid hydrolysis of an AGP from gum Arabic (Acacia Senegal) and analyses of the linkage types remaining indicated that a certain length of (1→3)-ß-linked galactose units was necessary for binding between the Yariv reagent and the AGP. This is in accordance to what also was recently observed by Kitazawa et al. (2013).


Subject(s)
Glucosides/chemistry , Gum Arabic/chemistry , Mucoproteins/chemistry , Phloroglucinol/analogs & derivatives , Diffusion , Dimethyl Sulfoxide/chemistry , Dimethylformamide/chemistry , Guanidine/chemistry , Mucoproteins/isolation & purification , Nuclear Magnetic Resonance, Biomolecular , Phloroglucinol/chemistry , Plant Proteins/chemistry , Plant Proteins/isolation & purification , Scattering, Radiation , Sodium Chloride/chemistry , Solvents/chemistry , Urea/chemistry , Water/chemistry
4.
Fitoterapia ; 80(4): 233-6, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19535013

ABSTRACT

Acylation of 3-O-angeloylingenol (1) with vinyl acetate, vinyl decanoate and vinyl cinnamate, catalyzed by Candida antarctica Lipase B, was investigated. In each case, compound 1 was quantitatively and regioselectively acylated to afford a single product, 3-O-angeloyl-20-O-acetylingenol (1a), 3-O-angeloyl-20-O-decanoylingenol (1b) and 3-O-angeloyl-20-O-cinnamoylingenol (1c), respectively. The structures of the novel compounds 1b-1c were determined by MS and NMR, and product 1a by comparison of RP-HPLC and TLC with a standard. Compounds 1b-1c induced a bipolar morphology of MM96L melanoma cells at a similar concentration as compound 1, as well as having activity in inhibiting the growth of MM96L melanoma cells.


Subject(s)
Antineoplastic Agents, Phytogenic/metabolism , Diterpenes/metabolism , Euphorbia/chemistry , Lipase/metabolism , Melanoma/drug therapy , Plant Extracts/metabolism , Acylation , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/therapeutic use , Cell Line, Tumor , Diterpenes/pharmacology , Diterpenes/therapeutic use , Fungal Proteins , Humans , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Vinyl Compounds/metabolism
6.
Planta Med ; 71(1): 59-66, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15678375

ABSTRACT

Pressed juices from Echinacea purpurea are used as non-specific immunostimulants, and arabinogalactan-proteins (AGPs) are part of the active principle. An AGP fraction was isolated from pressed juice of E. purpurea by precipitation with ss-glucosyl Yariv reagent, followed by gel-permeation chromatography. Polyclonal antibodies directed against the carbohydrate moiety of this AGP fraction showed a preferential specificity for E. purpurea AGPs from pressed juice over those extracted from E. purpurea suspension culture and other plant species. Native AGPs purified from this AGP fraction by RP-HPLC were then deglycosylated for N-terminal protein sequencing resulting in the identification of three major polypeptides. They show characteristic motifs of classical AGPs but also some features of extensins, suggesting these may be "hybrid" hydroxyproline-rich glycoproteins (HRGPs).


Subject(s)
Echinacea/chemistry , Mucoproteins/chemistry , Phytotherapy , Plant Proteins/chemistry , Chromatography, High Pressure Liquid , Humans
7.
Phytochemistry ; 62(2): 147-53, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12482449

ABSTRACT

Analysis of sterols in mycelia of the ascomycete, Leptosphaeria maculans by gas chromatography-mass spectrometry revealed that ergosterol comprised 95% of the total sterols, with eight other sterols comprising the remaining 5%. Six of these latter sterols were putative precursors of ergosterol and their presence suggested a pathway for ergosterol biosynthesis in this fungus. Ergosterol biosynthesis in fungi is inhibited by the triazole antifungal agent flutriafol. When L. maculans was grown in the presence of flutriafol, ergosterol content decreased while two 14 alpha-methylated sterols, 24-methylene dihydrolanosterol and obtusifoliol, accumulated.


Subject(s)
Ascomycota/chemistry , Mycelium/chemistry , Plant Diseases/microbiology , Sterols/biosynthesis , Sterols/isolation & purification , Ascomycota/metabolism , Gas Chromatography-Mass Spectrometry , Molecular Structure , Mycelium/metabolism , Sterols/chemistry , Time Factors
8.
Protoplasma ; 215(1-4): 128-39, 2001.
Article in English | MEDLINE | ID: mdl-11732052

ABSTRACT

Arabinogalactan proteins (AGPs) are proteoglycans secreted by plant cells that have been implicated in plant growth and development. Most AGPs cloned to date possess highly labile glycosylphosphatidylinositol (GPI) lipid anchors. These anchors transiently attach AGPs to the plasma membrane before they are released into the cell wall following GPI anchor hydrolysis. We have isolated and partially sequenced the protein core of an AGP purified from styles of Nicotiana alata. The protein sequence data were utilised to clone the AGP's gene, NaAGP4. This AGP shares about 78% sequence identity with the tomato AGP LeAGP-1. RNA gel blot analyses of different plant organs indicate that NaAGP4 is expressed in the same tissues and at similar levels as LeAGP-1. Furthermore, NaAGP4 like LeAGP-1 is rapidly suppressed by tissue wounding and by pathogen infection. We believe NaAGP4 and LeAGP-1 are the first described examples of orthologous AGPs from different plant species. In contrast, another AGP from N. alata, NaAGP1, is comparatively unaffected by wounding and pathogen infection, although this AGP is expressed in similar tissues and at similar levels as NaAGP4.


Subject(s)
Galactans/metabolism , Nicotiana/metabolism , Nicotiana/microbiology , Plant Proteins/metabolism , Amino Acid Sequence , Base Sequence , Botrytis/physiology , Chromatography, High Pressure Liquid , Galactans/chemistry , Galactans/genetics , Molecular Sequence Data , Plant Proteins/chemistry , Plant Proteins/genetics , Plant Structures/metabolism , Plant Structures/microbiology , Sequence Alignment , Nicotiana/chemistry , Nicotiana/genetics
9.
Plant Mol Biol ; 47(1-2): 161-76, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11554470

ABSTRACT

Arabinogalactan-proteins (AGPs) are a family of complex proteoglycans found in all higher plants. Although the precise function(s) of any single AGP is unknown, they are implicated in diverse developmental roles such as differentiation, cell-cell recognition, embryogenesis and programmed cell death. DNA sequencing projects have made possible the identification of the genes encoding a large number of putative AGP protein backbones. In contrast, our understanding of how AGPs undergo extensive post-translational modification is poor and it is important to understand these processes since they are likely to be critical for AGP function. Genes believed to be responsible for post-translational modification of an AGP protein backbone, include prolyl hydroxylases, glycosyl transferases, proteases and glycosylphosphatidylinositol-anchor synthesising enzymes. Here we examine models for proteoglycan function in animals and yeast to highlight possible strategies for determining the function(s) of individual AGPs in plants.


Subject(s)
Mucoproteins/genetics , Plant Proteins/genetics , Amino Acid Sequence , Arabidopsis/genetics , Arabidopsis/metabolism , Cell Wall/metabolism , Glycosylation , Glycosylphosphatidylinositols/metabolism , Molecular Sequence Data , Mucoproteins/metabolism , Mutation , Plant Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Sequence Alignment , Sequence Homology, Amino Acid
10.
Eur J Radiol ; 38(3): 205-8, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11399374

ABSTRACT

Traumatic aneurysms of the left subclavian artery and transverse cervical artery, subsequent to penetrating gunshot wound were diagnosed by angiography in 35-year-old patient. Subclavian artery aneurysm was treated by insertion of the Memotherm bare stent, whereas the false aneurysm of the transverse cervical artery was embolized with Gianturco's coils. The follow up examinations at 6 and 12 months showed good patency of subclavian artery.


Subject(s)
Aneurysm, False/surgery , Stents , Subclavian Artery/injuries , Wounds, Gunshot/complications , Adult , Aneurysm, False/diagnostic imaging , Aneurysm, False/etiology , Angiography , Arteries/injuries , Embolization, Therapeutic , Humans , Neck/blood supply , Shoulder Injuries , Subclavian Artery/diagnostic imaging
11.
Carbohydr Res ; 331(2): 163-71, 2001 Mar 22.
Article in English | MEDLINE | ID: mdl-11322730

ABSTRACT

The extracellular fungal polysaccharide, epiglucan, synthesised by Epicoccum nigrum is a side-chain/branched (1 --> 3;1 --> 6)-D-beta-glucan. Methylation analysis, 13C DEPT NMR and specific enzymic digestion data show slight variation in branching frequency among the epiglucans from the three strains examined. The (1 --> 3)-beta-linked backbone has (1 --> 6)-beta-linked branches at frequencies greater than the homologous glucans, scleroglucan and schizophyllan, from Sclerotium spp. and Schizophyllum commune, respectively. The structural analyses do not allow a distinction to be made between structures I and II. [structures: see text] Epiglucan displays non-Newtonian shear thinning rheological properties, typical of these glucans.


Subject(s)
Ascomycota/chemistry , Glucans/chemistry , Carbohydrate Conformation , Carbohydrate Sequence , Chromatography, Thin Layer , Glucan 1,3-beta-Glucosidase , Glucans/isolation & purification , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Molecular Structure , Spectrophotometry, Infrared , beta-Glucosidase/metabolism
12.
Int J Biol Macromol ; 28(5): 395-9, 2001 Jun 12.
Article in English | MEDLINE | ID: mdl-11325427

ABSTRACT

An anticoagulant was isolated from a marine green alga, Codium cylindricum. The anticoagulant was composed mainly of galactose with a small amount of glucose, and was highly sulfated (13.1% as SO3Na). The anticoagulant properties of the purified anticoagulant were compared with that of heparin by assays of activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) using normal human plasma. The anticoagulant showed similar activities with heparin, however, weaker than heparin. On the other hand, the anticoagulant did not affect PT even at the concentration at which APTT and TT were strongly prolonged. The anticoagulant did not potentiate antithrombin III (AT III) and heparin cofactor II (HC II), thus the anticoagulant mechanism would be different from that of other anticoagulants isolated so far from the genus Codium.


Subject(s)
Anticoagulants/isolation & purification , Anticoagulants/pharmacology , Blood Coagulation/drug effects , Chlorophyta/chemistry , Galactans/isolation & purification , Galactans/pharmacology , Thrombin/antagonists & inhibitors , Anticoagulants/chemistry , Antithrombins/analysis , Galactans/chemistry , Heparin/analysis , Humans , Sulfates/chemistry
13.
Plant Physiol ; 125(4): 2040-52, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11299383

ABSTRACT

The walls deposited by growing pollen tubes contain two types of beta-glucan, the (1,3)-beta-glucan callose and the (1,4)-beta-glucan cellulose, as well as various alpha-linked pectic polysaccharides. Pollen tubes of Nicotiana alata Link et Otto, an ornamental tobacco, were therefore used to identify genes potentially encoding catalytic subunits of the callose synthase and cellulose synthase enzymes. Reverse transcriptase-polymerase chain reactions (RT-PCR) with pollen-tube RNA and primers designed to conserved regions of bacterial and plant cellulose synthase (CesA) genes amplified a fragment that corresponded to an abundantly expressed cellulose-synthase-like gene named NaCslD1. A fragment from a true CesA gene (NaCesA1) was also amplified, but corresponding cDNAs could not be identified in a pollen-tube library, consistent with the very low level of expression of the NaCesA1 gene. RT-PCR with pollen-tube RNA and primers designed to regions conserved between the fungal FKS genes [that encode (1,3)-beta-glucan synthases] and their presumed plant homologs (the Gsl or glucan-synthase-like genes) amplified a fragment that corresponded to an abundantly expressed gene named NaGsl1. A second Gsl gene detected by RT-PCR (NaGsl2) was expressed at low levels in immature floral organs. The structure of full-length cDNAs of NaCslD1, NaCesA1, and NaGsl1 are presented. Both NaCslD1 and NaGsl1 are predominantly expressed in the male gametophyte (developing and mature pollen and growing pollen tubes), and we propose that they encode the catalytic subunits of two beta-glucan synthases involved in pollen-tube wall synthesis. Different beta-glucans deposited in one cell type may therefore be synthesized by enzymes from different gene families.


Subject(s)
Arabidopsis Proteins , Gene Expression Regulation, Plant , Glucosyltransferases/genetics , Membrane Proteins , Nicotiana/enzymology , Nicotiana/genetics , Plants, Toxic , Pollen/enzymology , Schizosaccharomyces pombe Proteins , Amino Acid Sequence , Conserved Sequence , DNA Primers , Gene Expression Regulation, Enzymologic , Gene Library , Glucosyltransferases/chemistry , Models, Molecular , Molecular Sequence Data , Phylogeny , Plant Stems/enzymology , Pollen/genetics , Protein Structure, Secondary , Reverse Transcriptase Polymerase Chain Reaction , Sequence Alignment , Sequence Homology, Amino Acid , Transcription, Genetic
14.
Planta ; 214(2): 235-42, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11800387

ABSTRACT

Galactomannan was coupled to a protein carrier for the preparation of monoclonal antibodies. The monoclonal antibodies generated bound to galactomannans from different sources as well as to glucomannan and galactoglucomannan. One monoclonal antibody, BGM C6, was characterised and found to be specific for (1-->4)-beta-linked mannopyranosyl residues; it had a binding affinity estimated at 1x10(-6) M for the (1-->4)-beta-linked mannohexaose. BGM C6 was used in immunogold labelling studies to locate galactomannans in the endosperm walls of normal coconuts (Cocos nucifera L.) and those of the mutant makapuno at two different developmental stages. The pattern and intensity of antibody labelling varied for each type of coconut at the mature and immature stages, indicating differences in the galactomannan composition of the endosperm walls.


Subject(s)
Antibodies, Monoclonal/immunology , Cocos/chemistry , Mannans/analysis , Mannans/immunology , Seeds/chemistry , Cocos/immunology , Galactose/analogs & derivatives , Immunohistochemistry , Molecular Structure , Mutation , Protein Transport , Seeds/immunology
15.
Lijec Vjesn ; 122(7-8): 165-7, 2000.
Article in Croatian | MEDLINE | ID: mdl-11048457

ABSTRACT

The incidence of postoperative nausea and vomiting (PONV) has been studied in a prospective group of 92 female patients in the generative period, undergoing thyroid surgery. In a subgroup of 47 examinees we analyzed PONV incidence according to the surgery time within the frame of their menstrual cycle. The highest number was observed in periovulatory and premenstrual periods (p < 0.02). In the formal trial, 24 patients that randomly received ondansetron (8 mg in 4 mL i.v.) and significantly less PONV than their 21 placebo controls (4 mL saline i.v.): 4 or 16.8% vs. 11 or 53.6% (p < 0.04).


Subject(s)
Antiemetics/therapeutic use , Menstrual Cycle , Ondansetron/therapeutic use , Postoperative Nausea and Vomiting/prevention & control , Adult , Female , Humans
16.
Plant Cell ; 12(9): 1751-68, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11006345

ABSTRACT

Arabinogalactan proteins (AGPs) are extracellular proteoglycans implicated in plant growth and development. We searched for classical AGPs in Arabidopsis by identifying expressed sequence tags based on the conserved domain structure of the predicted protein backbone. To confirm that these genes encoded bona fide AGPs, we purified native AGPs and then deglycosylated and deblocked them for N-terminal protein sequencing. In total, we identified 15 genes encoding the protein backbones of classical AGPs, including genes for AG peptides-AGPs with very short backbones (10 to 13 amino acid residues). Seven of the AGPs were verified as AGPs by protein sequencing. A gene encoding a putative cell adhesion molecule with AGP-like domains was also identified. This work provides a firm foundation for beginning functional analysis by using a genetic approach.


Subject(s)
Arabidopsis/genetics , Galactans/genetics , Multigene Family , Amino Acid Sequence , Base Sequence , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , DNA, Complementary/chemistry , DNA, Complementary/genetics , Galactans/chemistry , Galactans/metabolism , Gene Expression Regulation, Plant , Genes, Plant/genetics , Glycosylphosphatidylinositols/metabolism , Molecular Sequence Data , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Analysis, DNA , Sequence Analysis, Protein , Tissue Distribution
17.
Plant Cell ; 12(5): 691-706, 2000 May.
Article in English | MEDLINE | ID: mdl-10810144

ABSTRACT

Specific cDNA fragments corresponding to putative cellulose synthase genes (CesA) were inserted into potato virus X vectors for functional analysis in Nicotiana benthamiana by using virus-induced gene silencing. Plants infected with one group of cDNAs had much shorter internode lengths, small leaves, and a "dwarf" phenotype. Consistent with a loss of cell wall cellulose, abnormally large and in many cases spherical cells ballooned from the undersurfaces of leaves, particularly in regions adjacent to vascular tissues. Linkage analyses of wall polysaccharides prepared from infected leaves revealed a 25% decrease in cellulose content. Transcript levels for at least one member of the CesA cellulose synthase gene family were lower in infected plants. The decrease in cellulose content in cell walls was offset by an increase in homogalacturonan, in which the degree of esterification of carboxyl groups decreased from approximately 50 to approximately 33%. The results suggest that feedback loops interconnect the cellular machinery controlling cellulose and pectin biosynthesis. On the basis of the phenotypic features of the infected plants, changes in wall composition, and the reduced abundance of CesA mRNA, we concluded that the cDNA fragments silenced one or more cellulose synthase genes.


Subject(s)
Gene Silencing , Glucosyltransferases/genetics , Nicotiana/enzymology , Plants, Toxic , Base Sequence , DNA, Complementary , Esterification , Glucosyltransferases/metabolism , Microscopy, Electron, Scanning , Molecular Sequence Data , Phenotype , Polysaccharides/metabolism , Sequence Homology, Nucleic Acid , Nicotiana/genetics , Nicotiana/ultrastructure , Transcription, Genetic
18.
Respiration ; 67(2): 153-8, 2000.
Article in English | MEDLINE | ID: mdl-10773786

ABSTRACT

BACKGROUND: The fact that pulmonary complications occur in 20-60% of the patients subjected to abdominal operations clearly indicates that the lungs are the most endangered organ during the postoperative period. OBJECTIVE: The aim of this study was to demonstrate the impact of cholecystectomy on postoperative respiratory disturbances by comparing the laparotomic cholecystectomy with laparoscopic gallbladder removal. PATIENTS AND METHODS: A hundred cholecystectomized patients were included in the prospective randomized clinical trial. Half of the patients were operated on by the laparotomic procedure, whereas the other half underwent laparoscopic cholecystectomy. Spirometric parameters, arterial blood gases, and acid-base balance were determined before the operation, and at 6, 24, 72 and 144 h postoperatively. Abdominal distension was assessed by auscultating intestinal peristaltics, abdominal circumference measurement, and time interval to restitution of defecation. RESULTS: Six hours postoperatively, the values of ventilation parameters decreased on average by 40-50% from the baseline preoperative values in both groups of patients. The group of patients submitted to laparotomic cholecystectomy had significantly lower spirometric values and slower recovery of the ventilation parameters than the laparoscopic cholecystectomy group. Abdominal circumference was significantly greater and the time needed for restitution of peristaltics and defecation was significantly longer in the laparotomic cholecystectomy group compared to the group of laparoscopic cholecystectomy. CONCLUSIONS: Statistically significant impairments including hypoxia, hypocapnia and hyperventilation were observed in the patients submitted to laparotomic cholecystectomy, indicating the presence of objective respiratory risk, especially in elderly patients and patients with obstructive pulmonary diseases or cardiac insufficiency.


Subject(s)
Cholecystectomy, Laparoscopic , Cholecystectomy/adverse effects , Gallbladder Diseases/surgery , Laparotomy/adverse effects , Respiratory Insufficiency/etiology , Respiratory Insufficiency/prevention & control , Abdomen/physiology , Cholecystectomy, Laparoscopic/adverse effects , Defecation/physiology , Evaluation Studies as Topic , Humans , Lung Volume Measurements , Peristalsis/physiology , Postoperative Complications/prevention & control , Prospective Studies , Pulmonary Gas Exchange/physiology , Recovery of Function/physiology , Respiratory Insufficiency/physiopathology , Spirometry , Treatment Outcome
19.
Planta ; 210(2): 261-8, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10664132

ABSTRACT

Microscopic examination of suspension- cultured cells of Phleum pratense L., Panicum miliaceum L., Phalarisaquatica L. and Oryza sativa L. showed that they were comprised of numerous root primordia. Polysaccharides secreted by these suspension cultures contained glycosyl linkages consistent with the presence of high proportions of root mucilage-like polysaccharides. In contrast, suspension-cultured cells of Hordeum vulgare L. contained mostly undifferentiated cells more typical of plant cells in suspension culture. The polysaccharides secreted by H. vulgare cultures contained mostly linkages consistent with the presence of glucuronoarabinoxylan. The soluble polymers secreted by cell-suspension cultures of Phleum pratense contained 70% carbohydrate, 14% protein and 6% inorganic material. The extracellular polysaccharides were separated into four fractions by anion-exchange chromatography using a gradient of imidazole-HCl at pH 7.0. From glycosyl-linkage analyses, five polysaccharides were identified: an arabinosylated xyloglucan (comprising 20% of the total polysaccharide), a glucomannan (6%), a type-II arabinogalactan (an arabinogalactan-protein; 7%), an acidic xylan (3%), and a root-slime-like polysaccharide, which contained features of type-II arabinogalactans and glucuronomannans (65%).


Subject(s)
Poaceae/metabolism , Polysaccharides/chemistry , Cell Wall/chemistry , Cells, Cultured , Chromatography, Ion Exchange , Poaceae/cytology , Polysaccharides/metabolism
20.
Proc Natl Acad Sci U S A ; 96(25): 14246-51, 1999 Dec 07.
Article in English | MEDLINE | ID: mdl-10588691

ABSTRACT

Arabinogalactan proteins (AGPs) are proteoglycans of higher plants, which are implicated in growth and development. We recently have shown that two AGPs, NaAGP1 (from Nicotiana alata styles) and PcAGP1 (from Pyrus communis cell suspension culture), are modified by the addition of a glycosylphosphatidylinositol (GPI) anchor. However, paradoxically, both AGPs were buffer soluble rather than membrane associated. We now show that pear suspension cultured cells also contain membrane-bound GPI-anchored AGPs. This GPI anchor has the minimal core oligosaccharide structure, D-Manalpha(1-2)-D-Manalpha(1-6)-D-Manalpha(1-4)-D-GlcN -inositol, which is consistent with those found in animals, protozoa, and yeast, but with a partial beta(1-4)-galactosyl substitution of the 6-linked Man residue, and has a phosphoceramide lipid composed primarily of phytosphingosine and tetracosanoic acid. The secreted form of PcAGP1 contains a truncated GPI lacking the phosphoceramide moiety, suggesting that it is released from the membrane by the action of a phospholipase D. The implications of these findings are discussed in relation to the potential mechanisms by which GPI-anchored AGPs may be involved in signal transduction pathways.


Subject(s)
Galactans/chemistry , Glycosylphosphatidylinositols/chemistry , Plant Proteins/chemistry , Cells, Cultured , Mass Spectrometry , Suspensions
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