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1.
Molecules ; 26(17)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34500820

RESUMO

Raman spectroscopy is a useful method in biological, biomedical, food, and agricultural studies, allowing the simultaneous examination of various chemical compounds and evaluation of molecular changes occurring in tested objects. The purpose of our research was to explain how the elimination of ω-fractions from the wheat gliadin complex influences the secondary structures of the remaining αßγ-gliadins. To this aim, we analyzed the endosperm of wheat kernels as well as gliadin proteins extracted from two winter wheat genotypes: wasko.gl+ (control genotype containing the full set of gliadins) and wasko.gl- (modified genotype lacking all ω-gliadins). Based on the decomposition of the amide I band, we observed a moderate increase in ß-forms (sheets and turns) at the expense of α-helical and random coil structures for gliadins isolated from the flour of the wasko.gl- line. Since ω-gliadins contain no cysteine residues, they do not participate in the formation of the disulfide bridges that stabilize the protein structure. However, they can interact with other proteins via weak, low-energetic hydrogen bonds. We conclude that the elimination of ω-fractions from the gliadin complex causes minor modifications in secondary structures of the remaining gliadin proteins. In our opinion, these small, structural changes of proteins may lead to alterations in gliadin allergenicity.

2.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445145

RESUMO

The main goal of growing plants under various photoperiods is to optimize photosynthesis for using the effect of day length that often acts on plants in combination with biotic and/or abiotic stresses. In this study, Brassica juncea plants were grown under four different day-length regimes, namely., 8 h day/16 h night, 12 h day/12 h night, 16 h day/8 h night, and continuous light, and were infected with a necrotrophic fungus Alternaria brassicicola. The development of necroses on B. juncea leaves was strongly influenced by leaf position and day length. The largest necroses were formed on plants grown under a 16 h day/8 h night photoperiod at 72 h post-inoculation (hpi). The implemented day-length regimes had a great impact on leaf morphology in response to A. brassicicola infection. They also influenced the chlorophyll and carotenoid contents and photosynthesis efficiency. Both the 1st (the oldest) and 3rd infected leaves showed significantly higher minimal fluorescence (F0) compared to the control leaves. Significantly lower values of other investigated chlorophyll a fluorescence parameters, e.g., maximum quantum yield of photosystem II (Fv/Fm) and non-photochemical quenching (NPQ), were observed in both infected leaves compared to the control, especially at 72 hpi. The oldest infected leaf, of approximately 30% of the B. juncea plants, grown under long-day and continuous light conditions showed a 'green island' phenotype in the form of a green ring surrounding an area of necrosis at 48 hpi. This phenomenon was also reflected in changes in the chloroplast's ultrastructure and accelerated senescence (yellowing) in the form of expanding chlorosis. Further research should investigate the mechanism and physiological aspects of 'green islands' formation in this pathosystem.


Assuntos
Alternaria/patogenicidade , Mostardeira/microbiologia , Mostardeira/fisiologia , Necrose/microbiologia , Necrose/patologia , Fotossíntese/fisiologia , Doenças das Plantas/microbiologia , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Fluorescência , Mostardeira/metabolismo , Necrose/metabolismo , Fotoperíodo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia
3.
Plants (Basel) ; 10(1)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418897

RESUMO

Alnus viridis (Chaix) DC., green alder, is a fast-growing shrub that grows expansively in the European mountainside. In Poland, A. viridis naturally occurs only in the Bieszczady Mountains (south-eastern part of the country), above the upper forest border. In this study, we assessed the potential of green alder to expand in post-farming areas in the Bieszczady Mountains. We investigated the effects of topographical, climatic, and edaphic characteristics of four various study sites on the physiological and morphological properties of A. viridis leaves in order to answer the question whether the growth of plants in lower positions improves their physiological condition to such an extent that it increases the species invasiveness. This is the first comprehensive ecophysiological study of this species to be carried out in this part of Europe. The photochemical efficiency of PSII, the chlorophyll content, and leaf 13C and 15N discrimination were analyzed. On the basis of leaf radiation reflection, coefficients such as reflectance indices of anthocyanins, carotenoids, flavonoids (ARI2, CRI1, FRI), photochemical index of reflection (PRI), and the water band index (WBI) were calculated. We observed favorable physiological effects in A. viridis plants growing in locations below the upper forest border compared to plants growing in higher locations. As a result, A. viridis may become an invasive species and disturb the phytocoenotic balance of plant communities of the altitudinal zones in the Polish Western Carpathians.

4.
Cells ; 9(10)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33092216

RESUMO

Black spot disease, caused by Alternaria brassicicola in Brassica species, is one of the most devastating diseases all over the world, especially since there is no known fully resistant Brassica cultivar. In this study, the visualization of black spot disease development on Brassica oleracea var. capitata f. alba (white cabbage) leaves and subsequent ultrastructural, molecular and physiological investigations were conducted. Inter- and intracellular hyphae growth within leaf tissues led to the loss of host cell integrity and various levels of organelle disintegration. Severe symptoms of chloroplast damage included the degeneration of chloroplast envelope and grana, and the loss of electron denseness by stroma at the advanced stage of infection. Transcriptional profiling of infected leaves revealed that photosynthesis was the most negatively regulated biological process. However, in infected leaves, chlorophyll and carotenoid content did not decrease until 48 hpi, and several chlorophyll a fluorescence parameters, such as photosystem II quantum yield (Fv/Fm), non-photochemical quenching (NPQ), or plant vitality parameter (Rdf) decreased significantly at 24 and 48 hpi compared to control leaves. Our results indicate that the initial stages of interaction between B. oleracea and A. brassicicola are not uniform within an inoculation site and show a complexity of host responses and fungal attempts to overcome host cell defense mechanisms. The downregulation of photosynthesis at the early stage of this susceptible interaction suggests that it may be a part of a host defense strategy, or, alternatively, that chloroplasts are targets for the unknown virulence factor(s) of A. brassicicola. However, the observed decrease of photosynthetic efficiency at the later stages of infection is a result of the fungus-induced necrotic lesion expansion.


Assuntos
Alternaria/ultraestrutura , Brassica/genética , Brassica/microbiologia , Regulação para Baixo , Interações Hospedeiro-Patógeno/genética , Fotossíntese , Doenças das Plantas/microbiologia , Transcrição Genética , Alternaria/fisiologia , Brassica/fisiologia , Brassica/ultraestrutura , Clorofila A/metabolismo , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Suscetibilidade a Doenças , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Células do Mesofilo/microbiologia , Células do Mesofilo/ultraestrutura , Fotossíntese/genética , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Fatores de Tempo
5.
Insects ; 11(8)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722420

RESUMO

Despite many studies of the aging process, questions about key factors ensuring longevity have not yet found clear answers. Temperature seems to be one of the most important factors regulating lifespan. However, the genetic background may also play a key role in determining longevity. The aim of this study was to investigate the relationship between the temperature, genetic background (fruit fly origin), and metabolic rate on lifespan. Experiments were performed with the use of the wild type Drosophila melanogaster fruit flies originating from Australia, Canada, and Benin and the reference OregonR strain. The metabolic rate of D. melanogaster was measured at 20 °C, 25 °C, and 28 °C in an isothermal calorimeter. We found a strong negative relationship between the total heat flow and longevity. A high metabolic rate leads to increased aging in males and females in all strains. Furthermore, our results showed that temperature has a significant effect on fecundity and body weight. We also showed the usefulness of the isothermal calorimetry method to study the effect of environmental stress conditions on the metabolic activity of insects. This may be particularly important for the forecasting of impact of global warming on metabolic activity and lifespan of various insects.

6.
Int J Mol Sci ; 21(12)2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32630603

RESUMO

The present work focused on the characterization of some physiological mechanisms activated upon powdery mildew inoculation of the susceptible barley cultivar Ingrid and its near-isogenic lines (NILs) carrying various resistant genes (Mla, Mlg and mlo). After inoculation with Blumeria graminis f. sp. hordei (Bgh), measurements of leaf reflectance and chlorophyll a fluorescence were performed 3 and 7 day post-inoculation (dpi), while hormone assays were made 7 dpi. Bgh-inoculated resistant genotypes were characterized by lowered leaf reflectance parameters that correlated with carotenoids (CRI) and water content (WBI) in comparison to inoculated Ingrid. The PSII activity (i.e., Fv/Fm, ETo/CSm and P.I.ABS) strongly decreased in susceptible Ingrid leaves when the disease symptoms became visible 7 dpi. In Mla plants with visible hypersensitive spots the PSII activity decreased to a lesser extent. Inoculation resulted in a very slight decrease of photosynthesis at later stage of infection in Mlg plants, whereas in resistant mlo plants the PSII activity did not change. Chlorophyll a fluorescence measurements allowed presymptomatic detection of infection in Ingrid and Mla. Changes in the homeostasis of 22 phytohormones (cytokinins, auxins, gibberellins and the stress hormones JA, SA and ABA) in powdery mildew inoculated barley are discussed in relation to resistance against this biotrophic pathogen.


Assuntos
Ascomicetos/patogenicidade , Hordeum/metabolismo , Doenças das Plantas/genética , Ascomicetos/efeitos dos fármacos , Clorofila A/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/genética , Hordeum/genética , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo
7.
Biol Futur ; 70(3): 185-197, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34554449

RESUMO

BACKGROUND AND AIMS: High light causes disturbances in photosynthetic phosphorylation or damage to the photosystem II (PSII) structure or even assimilation tissues. The value of the red/ far-red ratio (R/FR) provides the plant with information on the environmental light conditions, regulating, among others, photosynthetic activity and pigment composition of the plant. The response of the photosynthetic apparatus of the sporotrophophylls and nest leaves of Platycerium bifurcatum, grown for 6 months at the low or high R/FR ratio, were studied. Later, the plants were transferred to high light (1,200 µmol quantum • m-2 • s-1). METHODS: Changes in PSII photochemical activity were determined based on non-destructive methods of chlorophyll a fluorescence kinetics analysis. The measurement of radiation reflectance from the leaves allowed to determine the content of selected pigments related to the photosynthesis process and to assess changes in the Photochemical Reflectance Index. The calculation of reflectance difference and sensitivity analysis was used to identify so-called "stress-sensitive wavelengths". RESULTS AND DISCUSSION: Plant growth at high R/FR ratio prepares photosynthetic apparatus of ferns to high light and enables more efficient conversion of absorbed photons. The increase in the amount of photoprotective compounds allows the protection against photoinhibition in the sporotrophophyll leaves that play key roles in plant nutrition and reproduction.

8.
Ann Agric Environ Med ; 24(2): 229-236, 2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28664699

RESUMO

[b]Abstract Introduction and objective[/b]. Gluten proteins (gliadins and glutenins) are polymorphic wheat storage proteins of allergenic properties. Significant differences in chemical composition between both protein groups allow to expect highly specific immunological response of individual subunits and fractions in reactions with IgE sera of people allergic to wheat. The aim of these studies was to identify and characterize the most allergenic gluten proteins (GP) and nongluten proteins (NGP) occurred in two closely related wheat hybrid genotypes. [b]Materials and method.[/b] 3xC and 3xN wheat hybrids, which differ strongly in regard of gliadin composition, were analyzed. Seven people manifesting different symptoms of wheat allergy donated sera for the experiment. The technique of immunoblotting after SDS-PAGE was used for identification of allergenic subunits and fractions among GP and NGP. Immunologically active protein bands were visualized by chemiluminescence. [b]Results[/b]. Great variation of immunodetection spectra was observed. Results of immunoblotting showed LMW glutenins to be of highest, gliadins of medium, while NGP of lowest allergenicity for selected patients. The 43-kDa and 47-kDa LMW glutenin subunits, 40-kDa and 43-kDa γ-gliadin fractions and 49-kDa NGP can be considered as the most immunoreactive among all protein bands [b]separated by SDS-PAGE. CONCLUSION: [/b] The observed differentiation of immunodetection spectra allows to model highly specific IgE-binding profiles of allergenic wheat proteins attributed to individual patients with symptoms of gluten intolerance. Highly immunoreactive subunits and fractions among GP and NGP were identified. The observed immunoreactivity of 49 kDa NGP is worth to emphasize, as it has never been reported as wheat allergenic protein before.


Assuntos
Gliadina/imunologia , Glutens/imunologia , Imunoglobulina E/imunologia , Triticum/genética , Triticum/imunologia , Hipersensibilidade a Trigo/imunologia , Adulto , Idoso , Feminino , Genótipo , Gliadina/análise , Gliadina/genética , Glutens/análise , Glutens/genética , Humanos , Masculino , Pessoa de Meia-Idade , Triticum/química
9.
Plant Physiol Biochem ; 109: 355-364, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27810675

RESUMO

Phytohormone levels and the expression of genes encoding key enzymes participating in hormone biosynthetic pathways were investigated in pepper leaves inoculated with two different tobamoviruses. Obuda pepper virus (ObPV) inoculation led to the development of hypersensitive reaction (incompatible interaction), while Pepper mild mottle virus (PMMoV) inoculation resulted in a systemic, compatible interaction. ObPV-inoculation markedly increased not only the levels of salicylic acid (SA) (73-fold) and jasmonic acid (8-fold) but also those of abscisic acid, indole-3-acetic acid, indole-3-butyric acid, cis-zeatin, cis-zeatin-9-riboside and trans-zeatin-9-riboside in the inoculated pepper leaves 3 days post inoculation. PMMoV infection increased only the contents of gibberellic acid and SA. Hormone contents did not change significantly after ObPV or PMMoV infection in non-infected upper leaves 20 days post inoculation. Concentrations of some brassinosteroids (BRs) and progesterone increased both in ObPV- and PMMoV inoculated leaves. ObPV inoculation markedly induced the expression of three phenylalanine ammonia-lyase (PAL) and a 1-aminocyclopropane-1-carboxylate oxidase (ACO) genes, while that of an isochorismate synthase (ICS) gene was not modified. PMMoV inoculation did not alter the expression of PAL and ICS genes but induced the transcript abundance of ACO although later than ObPV. Pre-treatment of pepper leaves with exogenous 24-epi-brassinolide (24-epi-BR) prior to ObPV-inoculation strongly mitigated the visible symptoms caused by ObPV. In addition, 24-epi-BR pre-treatment markedly altered the level of several hormones in pepper leaves following ObPV-inoculation. These data indicate that ObPV- and PMMoV-inoculations lead to intricate but well harmonized hormonal responses that are largely determined by the incompatible or compatible nature of plant-virus interactions.


Assuntos
Capsicum/metabolismo , Capsicum/virologia , Interações Hospedeiro-Patógeno/fisiologia , Doenças das Plantas/virologia , Tobamovirus/patogenicidade , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Capsicum/genética , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Interações Hospedeiro-Patógeno/genética , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Progesterona/metabolismo , Transdução de Sinais , Especificidade da Espécie , Tobamovirus/classificação
10.
J Plant Physiol ; 204: 36-43, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27500555

RESUMO

Photosynthetic processes in the leaf lamina and midribs of Plantago media were investigated using plants grown in high light (HL) or low light (LL) conditions. The fluorescence parameters, which indicate photochemical/photosynthetic activity, were different in HL and LL grown plants, but no major differences between lamina and midribs were found. An OJIP test (chlorophyll a fluorescence transient induction) of LL grown plants, indicative of the chloroplast electron transport chain, also showed both tissues to be similar. In HL plants, a partial blockage of electron flow between QA (the primary plastoquinone electron acceptor of PSII) and QB (the secondary plastoquinone acceptor of PSII) was found, and this was less visible in midribs. The effective dissipation of quantum energy per reaction center (DI0/RC) was similar in both tissues of HL grown plants, while in the midribs of LL leaves, this process seemed to be less effective. Measurements of 13C discrimination showed that the midrib tissues of LL and HL leaves effectively used ß-carboxylation products to accumulate their biomass. Thus, the well protected activity of electron transport in midribs with their limited capacity to fix CO2 from the air may indicate the involvement of this tissue in ß-carboxylation, transport or signaling. Carbon accumulated in roots showed a lower 13C discrimination value (more negative) than the values observed in lamina. This could indicate that roots are supplied with assimilates mostly during the light phase of the day cycle with intensive C3 photosynthesis.


Assuntos
Fotossíntese , Folhas de Planta/fisiologia , Feixe Vascular de Plantas/fisiologia , Plantago/fisiologia , Isótopos de Carbono , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A , Fluorescência , Peróxido de Hidrogênio/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
11.
Age (Dordr) ; 38(1): 11, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26783001

RESUMO

Despite many controversies, the yeast Saccharomyces cerevisiae continues to be used as a model organism for the study of aging. Numerous theories and hypotheses have been created for several decades, yet basic mechanisms of aging have remained unclear. Therefore, the principal aim of this work is to propose a possible mechanism leading to increased longevity in yeast. In this paper, we suggest for the first time that there is a link between decreased metabolic activity, fertility and longevity expressed as time of life in yeast. Determination of reproductive potential and total lifespan with the use of fob1Δ and sfp1Δ mutants allows us to compare the "longevity" presented as the number of produced daughters with the longevity expressed as the time of life. The results of analyses presented in this paper suggest the need for a change in the definition of longevity of yeast by taking into consideration the time parameter. The mutants that have been described as "long-lived" in the literature, such as the fob1Δ mutant, have an increased reproductive potential but live no longer than their standard counterparts. On the other hand, the sfp1Δ mutant and the wild-type strain produce a similar number of daughter cells, but the former lives much longer. Our results demonstrate a correlation between the decreased efficiency of the translational apparatus and the longevity of the sfp1Δ mutant. We suggest that a possible factor regulating the lifespan is the rate of cell metabolism. To measure the basic metabolism of the yeast cells, we used the isothermal microcalorimetry method. In the case of sfp1Δ, the flow of energy, ATP concentration, polysome profile and translational fitness are significantly lower in comparison with the wild-type strain and the fob1Δ mutant.


Assuntos
Envelhecimento/metabolismo , DNA/genética , Longevidade/fisiologia , Saccharomyces cerevisiae/metabolismo , Envelhecimento/genética , Meios de Cultura , Genótipo , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
12.
Plant Physiol Biochem ; 83: 267-78, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25194777

RESUMO

Leaves of a pepper cultivar harboring the L(3) resistance gene were inoculated with Obuda pepper virus (ObPV), which led to the appearance of hypersensitive necrotic lesions approx. 72 h post-inoculation (hpi) (incompatible interaction), or with Pepper mild mottle virus (PMMoV) that caused no visible symptoms on the inoculated leaves (compatible interaction). ObPV inoculation of leaves resulted in ion leakage already 18 hpi, up-regulation of a pepper carotenoid cleavage dioxygenase (CCD) gene from 24 hpi, heat emission and declining chlorophyll a content from 48 hpi, and partial desiccation from 72 hpi. After the appearance of necrotic lesions a strong inhibition of photochemical energy conversion was observed, which led to photochemically inactive leaf areas 96 hpi. However, leaf tissues adjacent to these inactive areas showed elevated ΦPSII and Fv/Fm values proving the advantage of chlorophyll a imaging technique. PMMoV inoculation also led to a significant rise of ion leakage and heat emission, to the up-regulation of the pepper CCD gene as well as to decreased PSII efficiency, but these responses were much weaker than in the case of ObPV inoculation. Chlorophyll b and total carotenoid contents as measured by spectrophotometric methods were not significantly influenced by any virus inoculations when these pigment contents were calculated on leaf surface basis. On the other hand, near-infrared FT-Raman spectroscopy showed an increase of carotenoid content in ObPV-inoculated leaves suggesting that the two techniques detect different sets of compounds.


Assuntos
Capsicum , Clorofila , Fluorescência , Folhas de Planta , Tobamovirus , Capsicum/química , Capsicum/metabolismo , Capsicum/virologia , Clorofila/química , Clorofila/metabolismo , Clorofila A , Dioxigenases/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/virologia , Proteínas de Plantas/metabolismo , Análise Espectral Raman , Tobamovirus/química , Tobamovirus/metabolismo
13.
J Plant Physiol ; 170(14): 1259-66, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23773692

RESUMO

The growth response and antioxidant capacity of Brassica oleracea var. capitata f. alba plants treated with 70ppb of ozone was examined. Four week old cabbage seedlings were fumigated with O3 for 3 days before being transplanted into the growing field. The effect of O3 treatment was determined directly after fumigation and over the course of field cultivation. Plants subjected to O3 treatment had an increased diameter of rosettes and number of leaves after 3 and 7 weeks in agriculture, respectively. In addition, the vast majority of fumigated plants reached marketable quality faster than control plants, indicating a positive role of episodes of increased O3 concentrations during vegetation on growth and yielding. Our analysis revealed that by fumigating juvenile white cabbage plants with moderate doses of O3 the activity of catalases (CAT) and peroxidases was elevated. The activity of the examined enzymes was not affected directly after fumigation, but it increased after several weeks in the experimental field. Increased CAT activity was accompanied by changes in 2 out of the 3 CAT genes CAT1 and CAT2, where CAT2 seemed to be responsible for the induced CAT activity. The biosynthesis of low-molecular stress protectants - tocopherols and the glucosinolate (GLS) sinigrin was transiently affected by ozone. γ-Tocopherol (γ-toc) content significantly increased directly after fumigation, but after 3 weeks of vegetation in the field its concentration reached values similar to control. The biosynthesis of α-tocopherol (α-toc) and sinigrin seemed to be upregulated in fumigated plants. However, the response was delayed; no differences were registered directly after treatment, but 3 weeks after transplanting the concentration of sinigrin and α-toc was elevated.


Assuntos
Antioxidantes/metabolismo , Brassica/crescimento & desenvolvimento , Brassica/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ozônio/farmacologia , Brassica/metabolismo , Relação Dose-Resposta a Droga , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
14.
Przegl Lek ; 70(12): 1043-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24720124

RESUMO

Gliadins and glutenins--the main components of wheat gluten--are highly complex and polymorphic proteins of wheat kernels. They are also allergenic proteins causing a range of food allergies. We hypothesized that the diversity of chemical structures and properties may relate to the diversification of immunoreactive properties of various subunits and fractions of gluten proteins. In the present study we used IgE sera, obtained from patients manifesting different symptoms of wheat allergies, for immunobloting analysis, to prove the specificity of immunological reaction between IgE antibodies and individual gliadins and glutenins, separated by SDS-PAGE. The results suggest that patients have different characteristics of IgE binding to the separated protein subunits and fractions. Sera of two patients showed strong binding of omega-gliadins, while alpha-gliadins and LMW glutenin subunits of MW = 43 and 45 kDa were highly allergenic for two other subjects in the test group of patients.


Assuntos
Epitopos/imunologia , Galectina 3/imunologia , Hipersensibilidade a Trigo/imunologia , Adulto , Alérgenos/imunologia , Feminino , Gliadina/imunologia , Humanos , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Triticum/imunologia
15.
Acta Biochim Pol ; 55(4): 707-11, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19081853

RESUMO

The presence and location of specific binding sites for progesterone and 17beta-estradiol in cells of wheat were estimated using radioligand binding assay. Membrane and cytosolic fractions of non-vernalized and vernalized plants were tested using tritium-labelled ligands. Specific binding of [(3)H]progesterone and [(3)H]17beta-estradiol occurs in wheat cells. The binding sites are located in membranes and in the cytosol. Specific binding of [(3)H]17beta-estradiol is higher in the membranes than in the cytosol. Specific binding of both ligands in the cytosolic fraction is higher in vernalized plants than in non-vernalized ones. The possibility of the occurrence of steroid binding proteins specific for progesterone and 17beta-estradiol, putative steroid receptors for these steroids in Triticum aestivum L., is discussed.


Assuntos
Estradiol/metabolismo , Progesterona/metabolismo , Triticum/metabolismo , Animais , Sítios de Ligação , Feminino , Ligantes , Ratos , Triticum/citologia , Útero/metabolismo
16.
New Phytol ; 180(2): 501-510, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18681935

RESUMO

The root endophytic basidiomycete Piriformospora indica has been shown to increase resistance against biotic stress and tolerance to abiotic stress in many plants. Biochemical mechanisms underlying P. indica-mediated salt tolerance were studied in barley (Hordeum vulgare) with special focus on antioxidants. Physiological markers for salt stress, such as metabolic activity, fatty acid composition, lipid peroxidation, ascorbate concentration and activities of catalase, ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase and glutathione reductase enzymes were assessed. Root colonization by P. indica increased plant growth and attenuated the NaCl-induced lipid peroxidation, metabolic heat efflux and fatty acid desaturation in leaves of the salt-sensitive barley cultivar Ingrid. The endophyte significantly elevated the amount of ascorbic acid and increased the activities of antioxidant enzymes in barley roots under salt stress conditions. Likewise, a sustained up-regulation of the antioxidative system was demonstrated in NaCl-treated roots of the salt-tolerant barley cultivar California Mariout, irrespective of plant colonization by P. indica. These findings suggest that antioxidants might play a role in both inherited and endophyte-mediated plant tolerance to salinity.


Assuntos
Antioxidantes/metabolismo , Basidiomycota/metabolismo , Hordeum/metabolismo , Micorrizas/metabolismo , Tolerância ao Sal/fisiologia , Análise de Variância , Ácido Ascórbico/metabolismo , Ácidos Graxos/análise , Hordeum/crescimento & desenvolvimento , Temperatura Alta , Peroxidação de Lipídeos/fisiologia , Raízes de Plantas/metabolismo , Cloreto de Sódio/farmacologia
17.
J Biol Inorg Chem ; 13(6): 909-18, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18438690

RESUMO

A systematic study of the reduction of (ImH)[trans-RuCl(4)(dmso)(Im)] (NAMI-A; dmso is dimethyl sulfoxide, Im is imidazole), a promising antimetastasing agent, by L-ascorbic acid under physiological conditions is reported. Under blood plasma conditions (pH 7.4, 0.1-0.15 M NaCl , 37 degrees C) the rapid reduction of trans-[Ru(III)Cl(4)(dmso)(Im)](-) results in the formation of trans-[Ru(II)Cl(4)(dmso)(Im)](2-) within seconds, and is followed by successive dissociation of the chloride ligands, whereas neither dmso nor imidazole ligands are released during the reaction. Under our experimental conditions, the formation of the ascorbate dianion is the rate-determining step, and once it has formed it reacts rapidly with NAMI-A. Moreover, the NAMI-A complex is very unstable at physiological pH (7.4); therefore, the hydrolysis of NAMI-A cannot be excluded as a competing reaction. During hydrolysis, aquated derivatives via stepwise dissociation of chloride and dmso ligands are formed, and most of these species have a higher redox potential and are expected to be even more easily reduced by ascorbic acid. Thus, it is very likely that the reduced form of NAMI-A or the reduction products of its hydrolytic derivatives react with albumin. The reaction of reduced NAMI-A with human serum albumin leads to the formation of stable adducts, with a binding efficiency very similar to that of the parent complex, viz., 3.2+/-0.3 and 4.0+/-0.4 mol of Ru(II) and Ru(III) per mole of albumin, respectively, however with a significantly higher reactivity.


Assuntos
Dimetil Sulfóxido/análogos & derivados , Compostos Organometálicos/química , Albumina Sérica/química , Ácido Ascórbico/química , Dimetil Sulfóxido/química , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Oxirredução , Compostos de Rutênio , Fatores de Tempo
18.
J Chem Ecol ; 32(12): 2569-83, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17131190

RESUMO

One commonly observed effect of phytotoxic compounds is the inhibition or delay of germination of sensitive seeds. Mustard (Sinapis alba L.) seeds were incubated with aqueous extracts of sunflower (Helianthus annuus L.) leaves. Although sunflower phytotoxins did not influence seed viability, extracts completely inhibited seed germination. Inhibition of germination was associated with alterations in reserve mobilization and generation of energy in the catabolic phase of germination. Degradation of lipids was suppressed by sunflower foliar extracts resulting in insufficient carbohydrate supply. The lack of respiratory substrates and decrease in energy (ATP) generation resulted in suppression of the anabolic phase of seed germination and ultimately growth inhibition.


Assuntos
Germinação/efeitos dos fármacos , Helianthus/química , Extratos Vegetais/farmacologia , Sinapis/efeitos dos fármacos , Toxinas Biológicas/farmacologia , Trifosfato de Adenosina/biossíntese , Metabolismo Energético/efeitos dos fármacos , Metabolismo dos Lipídeos , Sementes/efeitos dos fármacos , Sementes/fisiologia , Sinapis/crescimento & desenvolvimento
19.
Folia Histochem Cytobiol ; 43(2): 71-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16044944

RESUMO

The occurrence of mammalian sex hormones and their physiological role in plants is reviewed. These hormones, such as 17beta-estradiol, androsterone, testosterone or progesterone, were present in 60-80% of the plant species investigated. Enzymes responsible for their biosynthesis and conversion were also found in plants. Treatment of the plants with sex hormones or their precursors influenced plant development: cell divisions, root and shoot growth, embryo growth, flowering, pollen tube growth and callus proliferation. The regulatory abilities of mammalian sex hormones in plants makes possible their use in practice, especially in plant in vitro culture.


Assuntos
Hormônios Esteroides Gonadais/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Fenômenos Fisiológicos Vegetais , Animais , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/metabolismo , Mamíferos , Desenvolvimento Vegetal , Reprodução
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