Mansonone accumulation in elm callus induced by elicitors of Ophiostoma ulmi, and general properties of elicitors

1989 ◽  
Vol 67 (12) ◽  
pp. 3490-3497 ◽  
Author(s):  
D. Yang ◽  
R. S. Jeng ◽  
M. Hubbes

Fungal culture filtrates, cytoplasm, and cell walls of Ophiostoma ulmi contain molecules that elicit mansonone (phytoalexin) accumulation in elm calli. The elicitors from nonaggressive isolate Q311 cause a more rapid reaction on bioassays than those from the aggressive isolate MH75. On the callus of a susceptible elm (Ulmus americana), the elicitors from both isolates cause higher amounts of mansonone production than on the callus of a resistant elm (Ulmus pumila). These elicitors are heat stable, and their eliciting activities are partially sensitive to NaIO4, pronase E, proteinase K, and various hydrolytic enzymes. However, β-glucosidase treated elicitors have increased eliciting activities. The binding of Q311 culture filtrate elicitors to a concanavalin A – sepharose 4B column suggests that glycoproteins may be involved in elicitation. Some abiotic factors stimulate only small amounts of mansonone F accumulation in treated elm cells.


2020 ◽  
Vol 21 (5) ◽  
pp. 497-506
Author(s):  
Mayck Silva Barbosa ◽  
Bruna da Silva Souza ◽  
Ana Clara Silva Sales ◽  
Jhoana D’arc Lopes de Sousa ◽  
Francisca Dayane Soares da Silva ◽  
...  

Latex, a milky fluid found in several plants, is widely used for many purposes, and its proteins have been investigated by researchers. Many studies have shown that latex produced by some plant species is a natural source of biologically active compounds, and many of the hydrolytic enzymes are related to health benefits. Research on the characterization and industrial and pharmaceutical utility of latex has progressed in recent years. Latex proteins are associated with plants’ defense mechanisms, against attacks by fungi. In this respect, there are several biotechnological applications of antifungal proteins. Some findings reveal that antifungal proteins inhibit fungi by interrupting the synthesis of fungal cell walls or rupturing the membrane. Moreover, both phytopathogenic and clinical fungal strains are susceptible to latex proteins. The present review describes some important features of proteins isolated from plant latex which presented in vitro antifungal activities: protein classification, function, molecular weight, isoelectric point, as well as the fungal species that are inhibited by them. We also discuss their mechanisms of action.



2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Longfei Li ◽  
Ruirui Shi ◽  
Jianlan Gu ◽  
Yunn Chyn Tung ◽  
Yan Zhou ◽  
...  

AbstractNeurofibrillary tangles (NFTs) made of abnormally hyperphosphorylated tau are a hallmark of Alzheimer’s disease (AD) and related tauopathies. Regional distribution of NFTs is associated with the progression of the disease and has been proposed to be a result of prion-like propagation of misfolded tau. Tau in AD brain is heterogenous and presents in various forms. In the present study, we prepared different tau fractions by sedimentation combined with sarkosyl solubility from AD brains and analyzed their biochemical and pathological properties. We found that tau in oligomeric fraction (O-tau), sarkosyl-insoluble fractions 1 and 2 (SI1-tau and SI2-tau) and monomeric heat-stable fraction (HS-tau) showed differences in truncation, hyperphosphorylation, and resistance to proteinase K. O-tau, SI1-tau, and SI2-tau, but not HS-tau, were hyperphosphorylated at multiple sites and contained SDS- and β-mercaptoethanol–resistant high molecular weight aggregates, which lacked the N-terminal portion of tau. O-tau and SI2-tau displayed more truncation and less hyperphosphorylation than SI1-tau. Resistance to proteinase K was increased from O-tau to SI1-tau to SI2-tau. O-tau and SI1-tau, but not SI2-tau or HS-tau, captured tau from cell lysates and seeded tau aggregation in cultured cells. Heat treatment could not kill the prion-like activity of O-tau to capture normal tau. Hippocampal injection of O-tau into 18-month-old FVB mice induced significant tau aggregation in both ipsilateral and contralateral hippocampi, but SI1-tau only induced tau pathology in the ipsilateral hippocampus, and SI2-tau and HS-tau failed to induce any detectable tau aggregation. These findings suggest that O-tau and SI1-tau have prion-like activities and may serve as seeds to recruit tau and template tau to aggregate, resulting in the propagation of tau pathology. Heterogeneity of tau pathology within AD brain results in different fractions with different biological and prion-like properties, which may pose a major challenge in targeting tau for development of effective therapeutic treatments.



2007 ◽  
Vol 53 (2) ◽  
pp. 284-290 ◽  
Author(s):  
Sonia Chehimi ◽  
François Delalande ◽  
Sophie Sablé ◽  
Mohamed-Rabeh Hajlaoui ◽  
Alain Van Dorsselaer ◽  
...  

We report the isolation and characterization of a new bacteriocin, thuricin S, produced by the Bacillus thuringiensis subsp. entomocidus HD198 strain. This antibacterial activity is sensitive to proteinase K, is heat-stable, and is stable at a variety of pH values (3–10.5). The monoisotopic mass of thuricin S purified by high perfomance liquid chromatography, as determined with mass spectrometry ESI-TOF-MS, is 3137.61 Da. Edman sequencing and NanoESI-MS/MS experiments provided the sequence of the 18 N-terminal amino acids. Interestingly, thuricin S has the same N-terminal sequence (DWTXWSXL) as bacthuricin F4 and thuricin 17, produced by B. thuringiensis strains BUPM4 and NEB17, respectively, and could therefore be classified as a new subclass IId bacteriocin.



Trees ◽  
1990 ◽  
Vol 4 (4) ◽  
Author(s):  
LucC. Duchesne ◽  
R.S. Jeng ◽  
M. Hubbes ◽  
M.B. Sticklen


1963 ◽  
Vol 118 (6) ◽  
pp. 1009-1020 ◽  
Author(s):  
Zanvil A. Cohn ◽  
Edith Wiener

The influence of phagocytosis on the morphological and biochemical properties of macrophage hydrolase-containing granules has been studied in vitro. Following the uptake of large numbers of heat-killed bacteria, an intracellular rearrangement of hydrolytic enzymes occurred. This was associated with the solubilization of 50 to 60 per cent of the total cell content of acid phosphatase, cathepsin, lysozyme, beta glucuronidase, acid ribonuclease, and acid desoxyribonuclease and with a corresponding decrease in granule-bound enzyme. With more prolonged incubation the majority of the soluble intracellular pool of acid ribonuclease and lysozyme was lost to the extracellular medium. No change in the total content of any of the hydrolases was noted during 180 minutes of incubation in vitro. The morphological fate of the granules was studied by a histochemical method for acid phosphatase. After the phagocytosis of yeast cell walls there was a disappearance of acid phosphatase-positive granules and an accumulation of reaction product about the ingested particle. Experiments employing macrophages which were supravitally stained with neutral red also demonstrated the loss of neutral red-positive granules and the accumulation of the dye about the yeast cell walls. These results strongly suggest that lysis of macrophage granules occurs following phagocytosis and that a portion of the granule contents are then resegregated within the newly formed phagocytic vacuole.



2016 ◽  
Vol 15 (2) ◽  
pp. 122-132
Author(s):  
Jana Moravčíková ◽  
Denisa Margetínyová ◽  
Zdenka Gálová ◽  
Iwona Žur ◽  
Zuzana Gregorová ◽  
...  

Abstract The (1,3)-β-D-glucan also referred to as callose is a main component of cell walls of higher plants. Many physiological processes are associated with the changes in callose deposition. Callose is synthesised by the callose synthase complex while its degradation is regulated by the hydrolytic enzymes β-1,3-glucanases. The latter one specifically degrade (1,3)-β-D-glucans. This work is aimed to study β-1,3-glucanase activities in the leaves of plants at two leaf stage in two diploids (Agilops tauschii, Triticum monococcum L.), four tetraploids (Ae. cylindrica, Ae. triuncialis, T. araraticum, T. dicoccum) and two hexaploids (T. aestivum L, T. spelta L.). The leaves were subjected to qualitative and quantitative β-1,3-glucanase activity assays. Our results showed that the total β-1,3-glucanase activities were variable and genotype dependent. No significant correlation between β-1,3-glucanase activities and ploidy level was observed. The gel activity assays revealed a single fraction of ~52 kDa Glu1 that was found in all genotypes. The Glu1 fraction corresponds to a single or two acidic Glu isoforms in dependence on genotype. However, none of the acidic Glu fractions can be assigned as a specific for di-, tetra- or hexaploid genotypes. A single basic GluF isoform was detected and found as present in all genotypes.



1989 ◽  
Vol 35 (3) ◽  
pp. 349-358 ◽  
Author(s):  
Nicole Benhamou

Aplysia gonad lectin, isolated from the mollusc Aplysia depilans, was successfully conjugated to colloidal gold and used for ultrastructural detection of galacturonic acids in some pathogenic fungi. These sugar residues were found to occur in the fibrillar sheath surrounding hyphal cells of Ascocalyx abietina and in intravacuolar dense inclusions of this fungus spores. In hyphae and spores of Ophiostoma ulmi, galacturonic acids were detected mainly in the outermost wall layers. In contrast, these saccharides appeared associated with the innermost wall layers and especially the plasma membrane of Verticillium albo-atrum cells. Galacturonic acids were found to be absent in cells of Fusarium oxysporum f.sp. radicis-lycopersici and Candida albicans. These cytochemical data indicate therefore that a heterogeneity in wall composition exists between ascomycete fungi. The significance of the presence of galacturonic acids in the cell walls of certain fungi is still open to question.Key words: galacturonic acid, fungi, gold labeling, Aplysia depilans gonad lectin.



1995 ◽  
Vol 73 (10) ◽  
pp. 1604-1610 ◽  
Author(s):  
C. Hoffert ◽  
S. Gharibian ◽  
C. Breuil ◽  
D. L. Brown

Polyclonal antibodies were raised against proteinase K and were used to immunolocalize the major extracellular proteinase of the sap-staining fungus Ophiostoma piceae (Münch) H. and P. Sydow. Immunodot blotting showed that the IgG antibodies recognized both enzymes but reacted more strongly with proteinase K than with the O. piceae proteinase. Immunogold labelling and transmission electron microscopy revealed that the O. piceae proteinase was localized in the cell walls of O. piceae grown either in liquid media or wood. Key words: Ophiostoma piceae, proteinase, immunogold labelling, transmission electron microscopy, antibody, proteinase K.



1991 ◽  
Vol 69 (9) ◽  
pp. 2055-2073 ◽  
Author(s):  
Danny Rioux ◽  
G. B. Ouellette

Barrier zone formation was studied in small branches of Ulmus americana L., Prunus pensylvanica L.f., and Populus balsamifera L. following inoculation with Ophiostoma ulmi (Buism.) Nannf. (the Dutch elm disease pathogen). Barrier zones were continuous in the nonhosts whereas they were generally discontinuous in U. americana; barrier zone formation also occurred at a later stage of infection in the latter than in the former. Barrier zones were formed of parenchyma cells and fibers in U. americana, mainly of parenchyma cells in Prunus pensylvanica, and of fibers in Populus balsamifera. Fibers as a principal component of barrier zones are described for the first time. Histochemical tests revealed that the proportion of lignin was higher in barrier zone cell walls than in elements of the noninvaded xylem. Barrier zones contained suberized cells, the number of which was progressively greater in the order U. americana, Prunus pensylvanica, and Populus balsamifera. However, many fibers of U. americana occasionally formed a continuous barrier zone and had an internal layer that was slightly suberized. In addition, phenolic compounds were usually detected within barrier zone cells of these species. Key words: Dutch elm disease, nonhost plants, Ophiostoma ulmi, Ulmus americana, anatomy, histochemistry.



Author(s):  
Rosalind Vivia Tansy ◽  
Agus Budiawan Naro Putra ◽  
Takuya Sugahara

Petis, one of Indonesia’s traditional condiment, is most often made from shrimp and shrimp waste. Thiscondiment becomes popular as a savory flavor additive which is mainly produced in East Java, Indonesia.Despite the unique taste and good nutritional content, any particular study regarding its health benefit inIndonesia has not thoroughly evaluated yet. Therefore, the objective of this research was to explore petispotential towards anti-allergy property in vitro. The potential property was evaluated by determining theconcentration of Immunoglobulin E (IgE) by U266 cells treated with petis extract using ELISA. In result,petis extract could significantly suppressed IgE production up to 2-fold at its highest concentrationcompared to control. Further investigation to extrapolate petis functional bioactive compound wasconducted by treating petis extract with heat and enzyme (proteinase K). Result showed that heat- andenzyme-treated petis extract still have the ability to suppress IgE production by U266 cells. Thus, it couldbe assumed that the functional bioactive compound was a heat-stable non-protein compound. Thesepreliminary findings could conclude that petis extract has a potential anti-allergy property which gives anadded value towards petis product in Indonesia



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