scholarly journals Differential patterns of arabinosylation by membranes of suspension-cultured cells of Phaseolus vulgaris (French bean) after subculture or elicitation

1984 ◽  
Vol 222 (2) ◽  
pp. 427-435 ◽  
Author(s):  
G P Bolwell

Suspension-cultured cells of Phaseolus vulgaris (French bean) incorporated [1-3H] arabinose in vivo into high-Mr polymers that could be separated into glycoprotein and polysaccharide. Microsomal membranes from suspension-cultured cells of beans incorporated arabinose from UDP-beta-L-arabinose in vitro into both polysaccharide and glycoprotein. The enzyme involved in arabinan synthesis, arabinan synthase, appeared to be immunologically distinct from the protein:arabinosyltransferase system. Both these activities are inducible, but behave differently with either plant-growth-regulator or fungal-elicitor treatments. After subculture of cells entering the stationary growth phase the arabinan synthase activity reaches much higher values than does that of the protein transferase system during the initial period of cell division and growth, whereas after elicitation at the same growth stage, all the increased incorporation of arabinose occurs into glycoprotein of Mr higher than 200 000 and to a greater extent into a specific glycoprotein of Mr 42 500. Preliminary characterization of these glycoproteins prepared under non-reducing conditions and after acid and alkaline hydrolysis suggests that the high-Mr glycoprotein material is similar to arabinogalactan protein, whereas the lower-Mr material may be a hydroxyproline-rich protein existing as a dimer and that specifically increases during the hypersensitive response of the cells to the fungal elicitor from Colletotrichum lindemuthianum.

Bragantia ◽  
2005 ◽  
Vol 64 (2) ◽  
pp. 241-248
Author(s):  
Ademir Santini ◽  
Margarida Fumiko Ito ◽  
Jairo Lopes de Castro ◽  
Marcio Akira Ito ◽  
Juliana Cristina Goto

A cultura do feijoeiro (Phaseolus vulgaris L.) pode ser afetada por muitas doenças e dentre elas destaca-se a antracnose, causada pelo fungo Colletotrichum lindemuthianum. O acaricida azocyclotin (AZ) foi avaliado in vitro, em plântulas e em condições de campo, quanto ao efeito em C. lindemuthianum. Foram avaliados sete tratamentos in vitro: 1) testemunha; 2) AZ-1 mg L-1; 3) Trifenil hidróxido de estanho (THE)-1 mg L-1; 4) AZ-10 mg L-1; 5) THE-10 mg L-1; 6) AZ-100 mg L-1 e 7) THE-100 mg L-1 e 13 tratamentos in vivo: 1) testemunha; 2) AZ aplicado 24 horas antes da inoculação (AZ-24); 3) THE-24; 4) AZ-48; 5) THE-48; 6) AZ-72; 7) THE-72; 8) AZ-96; 9) THE-96; 10) AZ-120; 11) THE-120; 12) AZ-144 e 13) THE-144. Azocyclotin foi avaliado à dose de 125 g i.a.100 L-1 de água e trifenil hidróxido de estanho a 41,25 g i.a.100 L-1. Os delineamentos experimentais foram inteiramente ao acaso, com cinco repetições. Em condições de campo, foi realizado um experimento com seis tratamentos. Os tratamentos e as doses em g ha-1 de i.a foram: 1) tebuconazole + trifenil hidróxido de estanho (100 + 200); 2) tebuconazole + trifloxystrobin (40 + 100); 3) trifloxystrobin (125); 4) tebuconazole + azocyclotin (100 + 500); 5) azocyclotin (500) e 6) testemunha. O delineamento foi em blocos ao acaso, com quatro repetições. Para a avaliação in vitro foram medidos diâmetros ortogonais do crescimento micelial do fungo em BDA; in vivo e no campo usou-se escala de notas de 1 a 9, sendo 1 = sem sintoma e 9 = igual ou mais de 25% de área foliar afetada. In vitro, o tratamento 7 proporcionou maior inibição do desenvolvimento micelial. Em plântulas, observou-se controle de C. lindemuthianum até 144 horas, pelos dois produtos. Uma nova constatação em campo foi o controle de antracnose pelo acaricida azocyclotin, em que se observou também efeito sobre mancha-angular e mancha-de-alternária. Concluiu-se que o acaricida azocyclotin é eficiente no controle da antracnose do feijoeiro, semelhante ao trifenil hidróxido de estanho.


1991 ◽  
Vol 279 (1) ◽  
pp. 231-236 ◽  
Author(s):  
G P Bolwell ◽  
M W Rodgers

L-Phenylalanine ammonia-lyase (PAL; EC 4.3.1.5) purified from suspension-cultured cells of French bean (Phaseolus vulgaris) has been further characterized. A number of techniques, including use of an antiserum and affinity probes, have established that all the antigenic polypeptides represent polymorphic Mr forms of the enzyme. These peptides include an apparently higher-Mr (83,000) form which shows different kinetics of induction from the Mr-77000 forms that have been extensively characterized previously. The larger subunit appeared to be PAL by the following criteria: (a) binding to specific affinity and antibody matrices; (b) peptide mapping; (c) active-site labelling; and (d) amino acid composition. The increased Mr of the larger subunit was not completely attributable to glycosylation, although some sugar residues were detected in this Mr-83000 form but not in the other Mr forms. Mr-83000 subunits were also immunoprecipitated from translations in vitro of mRNA from cells that had been stressed for a long period. They were also detected in leaf tissues that were not yet undergoing an extensive wound response. This form of the enzyme may be constitutive and involved in the low-level accumulation of phenolics in most cell types. By contrast, the Mr-77000 forms of PAL were rapidly induced during elicitor action, wounding or cytokinin-induced xylogenesis as a key regulatory enzyme involved in the synthesis of phenolics under stress conditions or during differentiation.


1985 ◽  
Vol 229 (3) ◽  
pp. 693-699 ◽  
Author(s):  
G P Bolwell ◽  
M P Robbins ◽  
R A Dixon

The enzyme prolyl hydroxylase (proline: 2-oxoglutarate dioxygenase, EC 1.14.11.12), induced in suspension-cultured cells of Phaseolus vulgaris L. (French bean) by treatment with an elicitor preparation from the phytopathogenic fungus Colletotrichum lindemuthianum, has been investigated. The enzyme, which catalyses the hydroxylation of poly-L-proline with the stoichiometric decarboxylation of 2-oxoglutarate, has been shown to be localized mainly in smooth endoplasmic reticulum. After solubilization from microsomal membranes, the hydroxylase was purified by ion-exchange chromatography and affinity chromatography on poly-L-proline-Sepharose 4B. The subunit Mr, as assessed by sodium dodecyl sulphate/poly-acrylamide-gel electrophoresis, was 65 000, the subunit apparently being recovered as a doublet: the subunits associate under non-denaturing conditions to give at least a tetramer. The bean hydroxylase has kinetic properties and cofactor requirements similar to those previously reported for the enzyme from other plants. Elicitor treatment of suspension-cultured bean cells leads to a rapid induction of prolyl hydroxylase activity concomitant with induction of a protein: arabinosyl-transferase and increased levels of an arabinosylated hydroxyproline-rich protein.


Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.


Author(s):  
N.K.R. Smith ◽  
K.E. Hunter ◽  
P. Mobley ◽  
L.P. Felpel

Electron probe energy dispersive x-ray microanalysis (XRMA) offers a powerful tool for the determination of intracellular elemental content of biological tissue. However, preparation of the tissue specimen , particularly excitable central nervous system (CNS) tissue , for XRMA is rather difficult, as dissection of a sample from the intact organism frequently results in artefacts in elemental distribution. To circumvent the problems inherent in the in vivo preparation, we turned to an in vitro preparation of astrocytes grown in tissue culture. However, preparations of in vitro samples offer a new and unique set of problems. Generally, cultured cells, growing in monolayer, must be harvested by either mechanical or enzymatic procedures, resulting in variable degrees of damage to the cells and compromised intracel1ular elemental distribution. The ultimate objective is to process and analyze unperturbed cells. With the objective of sparing others from some of the same efforts, we are reporting the considerable difficulties we have encountered in attempting to prepare astrocytes for XRMA.Tissue cultures of astrocytes from newborn C57 mice or Sprague Dawley rats were prepared and cultured by standard techniques, usually in T25 flasks, except as noted differently on Cytodex beads or on gelatin. After different preparative procedures, all samples were frozen on brass pins in liquid propane, stored in liquid nitrogen, cryosectioned (0.1 μm), freeze dried, and microanalyzed as previously reported.


2020 ◽  
Author(s):  
Ian Sims ◽  
K Middleton ◽  
AG Lane ◽  
AJ Cairns ◽  
A Bacic

Microscopic examination of suspension-cultured cells of Phleum pratense L., Panicum miliaceum L., Phalaris aquatica 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%).


2020 ◽  
Author(s):  
Ian Sims ◽  
K Middleton ◽  
AG Lane ◽  
AJ Cairns ◽  
A Bacic

Microscopic examination of suspension-cultured cells of Phleum pratense L., Panicum miliaceum L., Phalaris aquatica 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%).


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii214-ii214
Author(s):  
Jenna Minami ◽  
Nicholas Bayley ◽  
Christopher Tse ◽  
Henan Zhu ◽  
Danielle Morrow ◽  
...  

Abstract Metabolic reprogramming is a hallmark of cancer, and malignant cells must acquire metabolic adaptations to fuel neoplastic progression. Mutations or changes in metabolic gene expression can impose nutrient dependencies in tumors, and even in the absence of metabolic defects, cancer cells can become auxotrophic for particular nutrients or metabolic byproducts generated by other cells in the tumor microenvironment (TME). Conventional cell lines do not recapitulate the metabolic heterogeneity of glioblastoma (GBM), while primary cultured cells do not account for the influences of the microenvironment and the blood brain barrier on tumor biology. Additionally, these systems are under strong selective pressure divergent from that in vivo, leading to reduced heterogeneity between cultured tumor cells. Here, we describe a biobank of direct-from-patient derived orthotopic xenografts (GliomaPDOX) and gliomaspheres that reveal a subset of gliomas that, while able to form in vivo, cannot survive in vitro. RNA sequencing of tumors that can form both in vivo and in vitro (termed “TME-Indifferent”) compared to that of tumors that can only form in vivo (termed “TME-Dependent”) revealed transcriptional changes associated with altered nutrient availability, emphasizing the unique metabolic programs impacted by the tumor microenvironment. Furthermore, TME-dependent tumors lack metabolic signatures associated with nutrient biosynthesis, thus indicating a potential dependency of these tumors on scavenging specific nutrients from the extracellular milieu. Collectively, these data emphasize the metabolic heterogeneity within GBM, and reveal a subset of gliomas that lack metabolic plasticity, indicating a potential brain-microenvironment specific metabolic dependency that can be targeted for therapy.


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