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1.
Sci Total Environ ; 572: 1322-1328, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26822471

RESUMO

The management of maritime pine in fire-prone habitats is a challenging task and fine-scale population genetic analyses are necessary to check if different fire recurrences affect genetic variability. The objective of this study was to assess the effect of fire recurrence on maritime pine genetic diversity using inter-simple sequence repeat markers (ISSR). Three maritime pine (Pinus pinaster Ait.) populations from Northern Portugal were chosen to characterize the genetic variability among populations. In relation to fire recurrence, Seirós population was affected by fire both in 1990 and 2005 whereas Vila Seca-2 population was affected by fire just in 2005. The Vila Seca-1 population has been never affected by fire. Our results showed the highest Nei's genetic diversity (He=0.320), Shannon information index (I=0.474) and polymorphic loci (PPL=87.79%) among samples from twice burned populations (Seirós site). Thus, fire regime plays an important role affecting genetic diversity in the short-term, although not generating maritime pine genetic erosion.


Assuntos
Incêndios , Variação Genética , Repetições de Microssatélites , Pinus/genética , Portugal
2.
Plant Biol (Stuttg) ; 13(2): 297-303, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21309976

RESUMO

Plants have developed many mechanisms to protect themselves against most potential microbial pathogens and diseases. Among these mechanisms, pathogenesis-related proteins are produced as part of the active defence to prevent attack. In this study, a full-length cDNA encoding the CsPR10 protein was identified in fresh saffron stigmas (Crocus sativus). The deduced amino acid sequence from the nucleotide sequence of the coding region showed homology with PR10 proteins. The clone expressed as a protein in fusion with a GST tag produced a 47-kDa protein in E. coli. CsPR10 had ribonuclease activity, with features common to class II-type ribonucleases; its specific activity was quantified as 68.8 U·mg(-1) protein, thus falling within the range of most PR10 proteins exhibiting RNase activity. Antifungal activity of CsPR10 was assayed against Verticillium dahliae, Penicillium sp. and Fusarium oxysporum. CsPR10 inhibited only F. oxysporum growth, and antifungal potency was reflected in a IC(50) of 8.3 µm. Expression analysis showed the presence of high transcript levels in anther and tepal tissues, low levels in stigmas and roots, and no signal detected in leaves. This protein seems to be involved in the active defence response through activation of the jasmonic acid pathway.


Assuntos
Crocus/genética , Proteínas de Plantas/metabolismo , Ribonucleases/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Crocus/metabolismo , Crocus/microbiologia , DNA Complementar/genética , DNA de Plantas/genética , Flores/genética , Flores/metabolismo , Fusarium/patogenicidade , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Penicillium/patogenicidade , Filogenia , Proteínas de Plantas/genética , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Ribonucleases/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Verticillium/patogenicidade
3.
J Investig Allergol Clin Immunol ; 20(5): 407-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20945607

RESUMO

BACKGROUND: Lipid transfer proteins (LTPs) are relevant allergens, and have recently been proposed as model plant allergens from fruit, vegetables, seeds, and pollens. However, no LTP spice allergen has been characterized to date. OBJECTIVES: To identify and isolate saffron LTPs and to explore their relevance in saffron allergy. METHODS: Six patients with rhinitis and positive skin prick test (SPT) results to saffron extract were selected. Two recombinant LTPs from saffron were isolated, cloned into pPIC9 plasmid, and produced in Pichia pastoris. Immunoglobulin (Ig) E immunodetection and enzyme-linked immunosorbent assays were performed with the 2 purified allergens and with the major peach allergen Pru p 3. RESULTS: Full cDNA corresponding to 2 saffron LTP variants was isolated and expressed in P pastoris. The molecular weight of rCro s 3.01 and rCro s 3.02 was 9.15 kDa and 9.55 kDa, respectively. The sequences obtained had a 47% identity with each other and 51% and 43% with Pru p 3. Both proteins were recognized by anti-Pru p 3 antibodies. Specific IgE to the purified allergens was found in 50% of patients for rCro s 3.01 and 33% for rCro s 3.02 and Pru p 3 in the saffron-allergic patients. CONCLUSIONS: Our results indicated that rCro s 3.01 and rCro s 3.02 are minor allergens of saffron, at least in the study patients. To our knowledge, this is the first report on the implication of LTPs in spice allergy.


Assuntos
Alérgenos/metabolismo , Antígenos de Plantas/metabolismo , Proteínas de Transporte/metabolismo , Hipersensibilidade Imediata/imunologia , Proteínas de Plantas/metabolismo , Alérgenos/genética , Alérgenos/imunologia , Alérgenos/isolamento & purificação , Sequência de Aminoácidos , Anticorpos/metabolismo , Antígenos de Plantas/genética , Antígenos de Plantas/imunologia , Antígenos de Plantas/isolamento & purificação , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Proteínas de Transporte/isolamento & purificação , Clonagem Molecular , Crocus , Humanos , Hipersensibilidade Imediata/sangue , Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/fisiopatologia , Imunoglobulina E/sangue , Dados de Sequência Molecular , Pichia , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Proteínas de Plantas/isolamento & purificação , Prunus , Rinite , Homologia de Sequência de Aminoácidos
4.
Int Arch Allergy Immunol ; 144(1): 39-43, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17496425

RESUMO

We report on a patient with anaphylaxis from mandarin. Temporal relationship between consumption of the fruit, the presence of positive specific IgE, the positive skin test and the basophil activation test for mandarin strongly supported the diagnosis of an IgE-mediated allergy from mandarin. The lipid transfer protein allergen from mandarin fruit was isolated and characterized. Specific IgE levels and IgE immunodetection data indicated the patient's sensitization to orange (Cit s 3) and mandarin (Cit r 3) lipid transfer protein allergens, as well as to germin-like (Cit s 1) allergen. These results were fully confirmed by skin prick test and basophil activation test (BAT) for lipid transfer proteins, and a BAT for Cit s 1. This case report has several particularities. First, in Central and Northern Europe, it is not widely appreciated that citrus fruits, particularly mandarin, can elicit anaphylaxis. Second, this case report re-emphasizes sensitization from lipid transfer proteins to predispose for severe allergic reactions. Finally, it provides an opportunity to summarize the applications of flow cytometry-assisted analysis and quantification of in vitro activated basophils in the diagnostic approach of anaphylaxis from food.


Assuntos
Alérgenos/imunologia , Alérgenos/isolamento & purificação , Anafilaxia/imunologia , Antígenos de Plantas/imunologia , Citrus/imunologia , Hipersensibilidade Alimentar/imunologia , Adulto , Sequência de Aminoácidos , Anafilaxia/patologia , Antígenos de Plantas/isolamento & purificação , Citrus/química , Feminino , Hipersensibilidade Alimentar/patologia , Humanos , Dados de Sequência Molecular
5.
Allergy ; 62(4): 408-14, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17362252

RESUMO

BACKGROUND: Peach allergy has two different patterns: central Europe with oral allergy syndrome (OAS) related to a primary sensitization to birch pollen Bet v 1 and profilins and southern Europe with mostly systemic symptoms, in many cases due to sensitization to lipid-transfer proteins. METHODS: Thirty peach-allergic patients with positive skin and food challenge tests and 29 control subjects were included. Skin prick tests (SPT) with inhalant allergens, commercial peach and apple extracts and native Pru p 3 were performed. In vitro specific immunoglobulin (Ig) E to grass pollen, birch pollen, peach, apple, rBet v 1, rBet v 2 and rPhl p 12 was determined by CAP, and rBet v 1, rMal d 1, rMal d 4, rMal d 3 and rPru p 3 using the ADVIA-Centaur platform. Basophil activation test (BAT) with commercial peach extract, commercial apple extract, nPru p 3, rMal d 3, rMal d 1 and rMal d 4 was also performed. RESULTS: Pru p 3 was the major allergen in the patient group from northern Spain. Sensitization to this allergen was found in 100% of the patients with systemic symptoms or contact urticaria. Only 60% of OAS patients were sensitized to Pru p 3, being all of them sensitized to profilins and 60% of them to allergens of the Bet v 1 family. Specific IgE determination and BAT using recombinant allergens (rPru p 3) show specificity and sensitivity values close to 100%. CONCLUSIONS: Most peach-allergic patients coming from the north of Spain present systemic symptoms after ingestion of peach, Pru p 3 being the main allergen. Patients with OAS present profilin-Bet v 1-related sensitization. Thus, in the north of Spain our patients show a mixed central-south Europe pattern with LTP-profilin-Bet v 1 sensitization depending on the symptoms presented. The use of natural and recombinant plant allergens, allows establishing the sensitization patterns to the different allergens studied.


Assuntos
Alérgenos/administração & dosagem , Antígenos de Plantas/administração & dosagem , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Imediata/imunologia , Adulto , Alérgenos/imunologia , Antígenos CD/imunologia , Antígenos de Plantas/imunologia , Basófilos/imunologia , Feminino , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/epidemiologia , Humanos , Hipersensibilidade Imediata/sangue , Hipersensibilidade Imediata/epidemiologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Proteínas de Plantas , Glicoproteínas da Membrana de Plaquetas/imunologia , Prunus/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Testes Cutâneos , Espanha/epidemiologia , Tetraspanina 30
6.
Allergy ; 60(11): 1424-9, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16197476

RESUMO

BACKGROUND: Orange is among the most widely consumed fruits, and among the plant food sources causing allergic reactions according to popular perception. However, its relevant allergenic components are virtually unknown. Profilin is a well-defined minor plant panallergen, showing prevalences around 30% in fruits and vegetables. METHODS: Twenty-three orange-allergic patients were studied. Natural orange profilin, named Cit s 2, was purified by affinity chromatography and characterized by N-terminal amino acid sequencing, matrix-assisted laser desorption/ionization mass spectrometry analysis and isolation of its coding cDNA. Reactivity to Cit s 2 was analyzed in vivo by skin prick tests (SPT) and in vitro by IgE immunodetection, specific IgE determination in individual sera and enzyme-linked immunosorbent assay-inhibition assays. RESULTS: The N-terminal amino acid sequence and molecular mass of natural Cit s 2, both fully in agreement with the complete amino acid sequence deduced from its coding cDNA, demonstrated its profilin nature. An unexpectedly high reactivity to Cit s 2 was found in vivo (78% of positive SPT responses) and in vitro (87% of sera from orange allergic patients had specific IgE to Cit s 2). The purified allergen inhibited around 50% of the IgE binding to an orange pulp extract. CONCLUSION: Orange profilin Cit s 2, unlike other plant food profilins, is a major and highly prevalent allergen.


Assuntos
Alérgenos/genética , Alérgenos/imunologia , Citrus sinensis/efeitos adversos , Hipersensibilidade Alimentar/etiologia , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Profilinas/genética , Profilinas/imunologia , Adolescente , Adulto , Alérgenos/isolamento & purificação , Sequência de Aminoácidos , Especificidade de Anticorpos , Antígenos de Plantas , Criança , Cromatografia de Afinidade , Citrus sinensis/química , Citrus sinensis/imunologia , Feminino , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/diagnóstico , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Lactente , Masculino , Dados de Sequência Molecular , Peso Molecular , Proteínas de Plantas/isolamento & purificação , Profilinas/isolamento & purificação , Alinhamento de Sequência , Testes Cutâneos
7.
Med Mycol ; 43(2): 153-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15832558

RESUMO

The water-soluble polysaccharide fraction of the cell wall alkali extract (F1SS) from the mycelial phase of the dimorphic fungus Paracoccidioides brasiliensis is compared with F1SS polysaccharides obtained from the Onygenalean mycelial fungi Ascocalvatia alveolata, Onygena equina and Aphanoascus terreus. These polymers were exclusively composed of mannose and galactose. Data from methylation and NMR analyses reveal that F1SS polysaccharides from the four fungi contain the same residues although in different proportions: [-->2,6)-alpha-D-Manp-(1 -->]; [2)-alpha-D-Manp-(1 -->]; [ -->6)-alpha-D-Manp-(1 -->]; and [alpha-D-Galf-(1 -->]. In P. brasiliensis, the repeating unit of the polysaccharide consists of a backbone of [(1 -->6)-alpha-D-Manp] substituted at the 0-2 position by the disaccharide [alpha-D-Galf-(1 -->6)-alpha-D-Manp-(1 -->], while the remaining 0-2 positions are substituted by single residues of mannose or short chains of (1 -->2)-mannose. The other species had a lower proportion of galactofuranose-containing side chains and higher proportion of mannose-containing side chains. The similarities found among the F1SS polysaccharides from P. brasiliensis and the Onygenalean A. alveolata, A. terreus and O. equina, reveal the close relatedness of all these fungi, show differences with polysaccharides from other fungal genera and agree with the molecular evidence provided in the scientific literature for the placement of P. brasiliensis within the Onygenales.


Assuntos
Parede Celular/química , Mananas/química , Onygenales/química , Paracoccidioides/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Mananas/isolamento & purificação , Dados de Sequência Molecular , Micélio/química
8.
Carbohydr Res ; 336(4): 325-8, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11728402

RESUMO

The structure of a cell wall alkali-extractable and water-soluble polysaccharide isolated from two species of Arachniotus has been established by reductive cleavage and NMR spectroscopy. The linear polysaccharide consists of a regular disaccharide-repeating unit with the structure: [-->6)-beta-D-Galf-(1-->5)-beta-D-Galf-(1-->](n)-->mannan core.


Assuntos
Ascomicetos/química , Parede Celular/química , Polissacarídeos/química , Dissacarídeos/química , Espectroscopia de Ressonância Magnética , Polissacarídeos/análise , Polissacarídeos/isolamento & purificação , Solubilidade
9.
Carbohydr Res ; 333(2): 173-8, 2001 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-11448679

RESUMO

The structure of a polysaccharide isolated from the cell wall of Hypocrea gelatinosa has been investigated by means of chemical analyses and 1D and 2D NMR spectroscopy. The polysacharide has an irregular structure, idealized as follows: [carbohydrate structure in text].


Assuntos
Parede Celular/química , Hypocreales/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular
10.
Arch Microbiol ; 173(4): 296-302, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10816049

RESUMO

The polysaccharides obtained from the alkali-extractable, water-soluble fraction (F1SS) from the cell wall of Myrothecium verrucaria and Myrothecium atroviride were shown to be composed of beta-(1-->6)-galactofuranose fully substituted at O-2 by terminal residues of alpha-glucopyranose and alpha-glucuronic acid. Glucuronic acid was substituted at O-4 by glucopyranose in the Myrothecium species M. inundatum, M. setiramosum, M. prestonii, M. tongaense and M. roridum. The acidic polysaccharides from Phaeostilbella atra (=Myrothecium atrum) and Myrothecium gramineum lacked the backbone of 2,6 di-O-substituted galactofuranose and contained a high amount of O-5-substituted beta-galactofuranose. The structures of the polysaccharides isolated from Myrothecium cinctum and Myrothecium penicilloides were unrelated to each other and to the polysaccharides from the other species analysed. The usefulness of these polysaccharides as a characteristic for delimitation of the genus Myrothecium is discussed.


Assuntos
Ascomicetos/classificação , Ascomicetos/genética , Parede Celular/química , Variação Genética , Polissacarídeos/química , Ascomicetos/química , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Polissacarídeos/análise
11.
Can J Microbiol ; 46(2): 101-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10721477

RESUMO

The chemical structure of cell walls and fractions of Verticillium fungicola, a pathogen of Agaricus bisporus, as well as their corresponding ultrastructures were studied. There are at least three chemically distinct types of carbohydrate polymers: one yielding mannose with lower amounts of galactose and glucose (glucogalactomannan), another one composed mainly of glucose (glucan), and a third one containing only N-acetylglucosamine (chitin). Attempts were made to locate these materials in situ by comparing electron micrographs of shadowed and sectioned cell walls, and also by indirect immunofluorescence. It was shown that none of these polymers constituted a completely physically distinct layer, but there seem to be different solubility properties in the outer, inner, and intermediate layers. It was also shown that fibrillar material (chitin) embedded in cementing glucan constituted the residual inner fraction of the original wall material. Indirect immunofluorescence showed the location of a significant amount of glucogalactomannan on the surface of the walls in which rodlet structures were visualized by electron microscopy.


Assuntos
Verticillium/química , Parede Celular/química , Parede Celular/ultraestrutura , Técnica Indireta de Fluorescência para Anticorpo , Metilação , Microscopia Eletrônica , Monossacarídeos/análise , Monossacarídeos/química , Polissacarídeos/análise , Polissacarídeos/química , Espectrofotometria Infravermelho , Verticillium/ultraestrutura
12.
Carbohydr Res ; 303(1): 67-72, 1997 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-9345753

RESUMO

The structure of acidic fungal polysaccharides, isolated from the cell wall of Cylindrocladium and Calonectria species, has been investigated by chemical analysis, methylation and reductive cleavage analyses, and 1D and 2D 1H and 13C NMR spectroscopy. The polysaccharides have an idealized repeating unit: [formula: see text] linked to a small mannan core (< 5%), with n = 3 for Cylindrocladium penicilloides and C. quinqueseptatum and n = 5 for Calonectria theae, C. crotalariae, and C. colhounii.


Assuntos
Ácidos Carboxílicos/química , Parede Celular/química , Fungos/química , Polissacarídeos/isolamento & purificação , Sequência de Carboidratos , Isótopos de Carbono , Fungos/ultraestrutura , Espectroscopia de Ressonância Magnética/métodos , Metilação , Dados de Sequência Molecular , Prótons
13.
Carbohydr Res ; 304(3-4): 281-91, 1997 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-9468630

RESUMO

The structure of fungal polysaccharides isolated from the cell wall of Trichoderma reesei, T. koningii, and Hypocrea psychrophila, have been investigated by means of chemical analyses and 1D and 2D NMR spectroscopy. The polysaccharides have an irregular structure, idealized as follows: [formula: see text] The proportions of the different side chains vary from a species to another, being n above some three times larger in H. psychrophila than in T. reesei or T. koningii.


Assuntos
Hypocreales/química , Polissacarídeos/química , Trichoderma/química , Configuração de Carboidratos , Sequência de Carboidratos , Parede Celular/química , Hypocreales/crescimento & desenvolvimento , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Polissacarídeos/isolamento & purificação , Trichoderma/crescimento & desenvolvimento
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