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1.
Sci Total Environ ; 927: 171917, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38580127

RESUMO

Lasiodiplodia hormozganensis, initially recognized as a fungal plant pathogen, is recognized now acknowledged as a potential threat to humans. However, our understanding of the pathogenesis mechanisms of Lasiodiplodia species remains limited, and the impact of temperature on its pathogenicity is unclear. This study aims to elucidate the effects of temperature on the biology of L. hormozganensis, focusing on the expression of pathogenesis-related molecules and its ability to function as a cross-kingdom pathogen. We conducted experiments at two different temperatures, 25 and 37 °C, analyzing the proteome and transcriptome of L. hormozganensis. Using strain CBS339.90, initially identified as L. theobromae but confirmed through ITS and tef1-α sequence analysis to be L. hormozganensis, we aimed to understand the fungus's protein expression under varying temperature conditions. Results from the functional analysis of the secretome at 25 °C showed a noteworthy presence of proteins related to carbohydrate metabolism, catabolism, plant cell wall degradation, and pathogenesis. However, when grown at 37 °C, the fungus exhibited an increased production of stress response and pathogenesis-related proteins. Our findings identified various pathways crucial for pathogenesis in both plants and humans, suggesting that L. hormozganensis possesses the genetic foundation to infect both hosts. Specific pathogenesis-related proteins, including the phytotoxin snodprot1, aspartic protease aspergillopepsin, and virulence protein SSD1, were also identified. Concluding, we propose a possible mechanism of how L. hormozganensis adapts to different temperatures. The shift in temperature results in the expression of genes that favor human related pathogenesis molecules.


Assuntos
Ascomicetos , Temperatura , Ascomicetos/fisiologia , Ascomicetos/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Transcriptoma
2.
J Fungi (Basel) ; 7(12)2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34947073

RESUMO

Aspergillus section Circumdati encompasses several species that express both beneficial (e.g., biochemical transformation of steroids and alkaloids, enzymes and metabolites) and harmful compounds (e.g., production of ochratoxin A (OTA)). Given their relevance, it is important to analyze the genetic and metabolic diversity of the species of this section. We sequenced the genome of Aspergillus affinis CMG 70, isolated from sea water, and compared it with the genomes of species from section Circumdati, including A. affinis's strain type. The A. affinis genome was characterized considering secondary metabolites biosynthetic gene clusters (BGCs), carbohydrate-active enzymes (CAZymes), and transporters. To uncover the biosynthetic potential of A. affinis CMG 70, an untargeted metabolomics (LC-MS/MS) approach was used. Cultivating the fungus in the presence and absence of sea salt showed that A. affinis CMG 70 metabolite profiles are salt dependent. Analyses of the methanolic crude extract revealed the presence of both unknown and well-known Aspergillus compounds, such as ochratoxin A, anti-viral (e.g., 3,5-Di-tert-butyl-4-hydroxybenzoic acid and epigallocatechin), anti-bacterial (e.g., 3-Hydroxybenzyl alcohol, l-pyroglutamic acid, lecanoric acid), antifungal (e.g., lpyroglutamic acid, 9,12,13-Trihydroxyoctadec-10-enoic acid, hydroxyferulic acid), and chemotherapeutic (e.g., daunomycinone, mitoxantrone) related metabolites. Comparative analysis of 17 genomes from 16 Aspergillus species revealed abundant CAZymes (568 per species), secondary metabolite BGCs (73 per species), and transporters (1359 per species). Some BGCs are highly conserved in this section (e.g., pyranonigrin E and UNII-YC2Q1O94PT (ACR toxin I)), while others are incomplete or completely lost among species (e.g., bikaverin and chaetoglobosins were found exclusively in series Sclerotiorum, while asperlactone seemed completely lost). The results of this study, including genome analysis and metabolome characterization, emphasize the molecular diversity of A. affinis CMG 70, as well as of other species in the section Circumdati.

3.
J Fungi (Basel) ; 8(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35049971

RESUMO

The genus Emericellopsis is found in terrestrial, but mainly in marine, environments with a worldwide distribution. Although Emericellopsis has been recognized as an important source of bioactive compounds, the range of metabolites expressed by the species of this genus, as well as the genes involved in their production are still poorly known. Untargeted metabolomics, using UPLC- QToF-MS/MS, and genome sequencing (Illumina HiSeq) was performed to unlock E. cladophorae MUM 19.33 chemical diversity. The genome of E. cladophorae is 26.9 Mb and encodes 8572 genes. A large set of genes encoding carbohydrate-active enzymes (CAZymes), secreted proteins, transporters, and secondary metabolite biosynthetic gene clusters were identified. Our analysis also revealed genomic signatures that may reflect a certain fungal adaptability to the marine environment, such as genes encoding for (1) the high-osmolarity glycerol pathway; (2) osmolytes' biosynthetic processes; (3) ion transport systems, and (4) CAZymes classes allowing the utilization of marine polysaccharides. The fungal crude extract library constructed revealed a promising source of antifungal (e.g., 9,12,13-Trihydroxyoctadec-10-enoic acid, hymeglusin), antibacterial (e.g., NovobiocinA), anticancer (e.g., daunomycinone, isoreserpin, flavopiridol), and anti-inflammatory (e.g., 2'-O-Galloylhyperin) metabolites. We also detected unknown compounds with no structural match in the databases used. The metabolites' profiles of E. cladophorae MUM 19.33 fermentations were salt dependent. The results of this study contribute to unravel aspects of the biology and ecology of this marine fungus. The genome and metabolome data are relevant for future biotechnological exploitation of the species.

4.
Int J Syst Evol Microbiol ; 70(10): 5337-5354, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32845832

RESUMO

Fungi are ubiquitous organisms with a wide distribution in almost all ecosystems, including marine environments. Coastal and estuarine ecosystems remain poorly unexplored as fungal habitats, potentially harbouring a hidden diversity with important ecological roles. During an extensive survey of marine fungi in coastal and estuarine Portuguese environments, a collection of 612 isolates was obtained from water, algae, sponges and driftwood. From these, 282 representative isolates were selected through microsatellite-primed PCR (MSP-PCR) fingerprinting analysis, which were identified based on DNA sequence data. The collection yielded 117 taxa from 38 distinct genera, which were identified using DNA sequence analysis. Overall, fungal community composition varied with host/substrate, but the most abundant taxa in the collection were Cladosporium cladosporioides, Penicillium terrigenum, Penicillium brevicompactum and Fusarium equiseti/incarnatum complex. The occurrence of a high fungal diversity harbouring novel species was disclosed. Through a multilocus phylogeny based on ITS, tub2 and tef1-α sequences, in conjunction with morphological and physiological data, we propose Neoascochyta fuci sp. nov. and Paraconiothyrium salinum sp. nov.


Assuntos
Ascomicetos/classificação , Filogenia , Água do Mar/microbiologia , Ascomicetos/isolamento & purificação , DNA Fúngico/genética , Ecossistema , Técnicas de Tipagem Micológica , Portugal , Análise de Sequência de DNA
5.
Mycologia ; 112(1): 154-171, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31829905

RESUMO

Macroalgae of the genera Fucus, Ulva, and Enteromorpha are typically abundant in estuaries. Endophytic fungi may have beneficial effects on the hosts affecting their ability to cope with stress. They are also a source of biologically active compounds. However, little is known about the endophytic fungi that colonize these macroalgae. Endophytic isolates were obtained from macroalgae from various sites in the estuary Ria de Aveiro (Portugal), as well as from saline water and sponges. Six Acremonium-like species could not be affiliated to any known species. Phylogenetic analyses based on internal transcribed spacer (ITS) region of the ribosomal DNA and ß-tubulin (tub2) and actin (act1) genes placed these species in the genera Emericellopsis and Parasarocladium, but distinct from all currently known species. Although sharing morphological characteristics with the most closely related species, these genera differ in micromorphological and molecular characters. Thus, three novel species of Emericellopsis (E. cladophorae, sp. nov., E. enteromorphae, sp. nov., and E. phycophila, sp. nov.) and three novel species of Parasarocladium (P. aestuarinum, sp. nov., P. alavariense, sp. nov., and P. fusiforme, sp. nov.) are proposed.


Assuntos
Estuários , Hypocreales/classificação , Alga Marinha/microbiologia , Animais , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Genes Fúngicos/genética , Hypocreales/citologia , Hypocreales/genética , Hypocreales/crescimento & desenvolvimento , Filogenia , Poríferos/microbiologia , Portugal , Água do Mar/microbiologia , Análise de Sequência de DNA
6.
Int J Mol Sci ; 20(23)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31816814

RESUMO

Lasiodiplodia theobromae is one of the most aggressive agents of the grapevine trunk disease Botryosphaeria dieback. Through a dual RNA-sequencing approach, this study aimed to give a broader perspective on the infection strategy deployed by L. theobromae, while understanding grapevine response. Approximately 0.05% and 90% of the reads were mapped to the genomes of L. theobromae and Vitis vinifera, respectively. Over 2500 genes were significantly differentially expressed in infected plants after 10 dpi, many of which are involved in the inducible defense mechanisms of grapevines. Gene expression analysis showed changes in the fungal metabolism of phenolic compounds, carbohydrate metabolism, transmembrane transport, and toxin synthesis. These functions are related to the pathogenicity mechanisms involved in plant cell wall degradation and fungal defense against antimicrobial substances produced by the host. Genes encoding for the degradation of plant phenylpropanoid precursors were up-regulated, suggesting that the fungus could evade the host defense response using the phenylpropanoid pathway. The up-regulation of many distinct components of the phenylpropanoid pathway in plants supports this hypothesis. Moreover, genes related to phytoalexin biosynthesis, hormone metabolism, cell wall modification enzymes, and pathogenesis-related proteins seem to be involved in the host responses observed. This study provides additional insights into the molecular mechanisms of L. theobromae and V. vinifera interactions.


Assuntos
Ascomicetos/fisiologia , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Análise de Sequência de RNA , Vitis/genética , Vitis/microbiologia , Sinalização do Cálcio , Ciclopentanos/metabolismo , Regulação para Baixo/genética , Etilenos/biossíntese , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Genes de Plantas , Modelos Biológicos , Oxilipinas/metabolismo , Fatores de Tempo , Regulação para Cima/genética
7.
MycoKeys ; 60: 31-44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31723336

RESUMO

A collection of fungi was isolated from macroalgae of the genera Gracilaria, Enteromorpha and Ulva in the estuary Ria de Aveiro in Portugal. These isolates were characterized through a multilocus phylogeny based on ITS region of the ribosomal DNA, beta-tubulin (tub2) and translation elongation factor 1 alpha (tef1-α) sequences, in conjunction with morphological and physiological data. These analyses showed that the isolates represented an unknown fungus for which a new genus, Neptunomyces gen. nov. and a new species, Neptunomyces aureus sp. nov. are proposed. Phylogenetic analyses supported the affiliation of this new taxon to the family Didymosphaeriaceae.

8.
Sci Rep ; 9(1): 13144, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511626

RESUMO

Lasiodiplodia theobromae (Botryosphaeriaceae, Ascomycota) is a plant pathogen and human opportunist whose pathogenicity is modulated by temperature. The molecular effects of temperature on L. theobromae are mostly unknown, so we used a multi-omics approach to understand how temperature affects the molecular mechanisms of pathogenicity. The genome of L. theobromae LA-SOL3 was sequenced (Illumina MiSeq) and annotated. Furthermore, the transcriptome (Illumina TruSeq) and proteome (Orbitrap LC-MS/MS) of LA-SOL3 grown at 25 °C and 37 °C were analysed. Proteins related to pathogenicity (plant cell wall degradation, toxin synthesis, mitogen-activated kinases pathway and proteins involved in the velvet complex) were more abundant when the fungus grew at 25 °C. At 37 °C, proteins related to pathogenicity were less abundant than at 25 °C, while proteins related to cell wall organisation were more abundant. On the other hand, virulence factors involved in human pathogenesis, such as the SSD1 virulence protein, were expressed only at 37 °C. Taken together, our results showed that this species presents a typical phytopathogenic molecular profile that is compatible with a hemibiotrophic lifestyle. We showed that L. theobromae is equipped with the pathogenesis toolbox that enables it to infect not only plants but also animals.


Assuntos
Ascomicetos/genética , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica , Proteômica/métodos , Temperatura , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/metabolismo , Humanos , Doenças das Plantas/microbiologia , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Vitis/microbiologia
9.
Int J Syst Evol Microbiol ; 69(12): 3769-3776, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31464661

RESUMO

The genus Verrucoconiothyrium was erected to accommodate Coniothyrium-like species with verruculose conidia. So far, it includes only four species, which have been found in association with plants, and very little is known about their distribution and host preferences. In this study, a Coniothyrium-like fungus isolated from sea water from the north of Portugal was characterised. Phylogenetic analysis, based on sequence data of the internal transcribed spacer and beta-tubulin loci, placed this fungus within the genus Verrucoconiothyrium but clearly distinct from the other known species. A novel species Verrucoconiothyrium ambiguumsp. nov. is described and illustrated. The taxonomic affiliation of the genus Verrucoconiothyrium at the family level was addressed through individual and combined gene genealogies. Our results show that the genus Verrucoconiothyrium is a member of the family Didymellaceae.


Assuntos
Ascomicetos/classificação , Filogenia , Água do Mar/microbiologia , Ascomicetos/isolamento & purificação , DNA Fúngico , Técnicas de Tipagem Micológica , Portugal , Análise de Sequência de DNA , Esporos Fúngicos
10.
Int J Syst Evol Microbiol ; 69(10): 3014-3021, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31219416

RESUMO

During an extensive survey of marine fungi in coastal marine environments from Portugal, a collection of Penicillium isolates were obtained from sea water, macroalgae and driftwood. Sixteen distinct Penicillium species were identified with Penicillium terrigenum and Penicillium brevicompactum being the most frequent. A Penicillium species isolated from sea water could not be affiliated to any known species. Phylogenetic analyses based on the ITS region of the rDNA and the beta-tubulin (benA) gene placed it into Penicillium section Ramosa, distinct from all currently known species and with Penicillium tunisiense as its closest relative. Although having similar morphological characteristics, these species differ in micromorphological and molecular characters. Thus, Penicillium lusitanum sp. nov. is proposed as a novel species.


Assuntos
Penicillium/classificação , Filogenia , Água do Mar/microbiologia , Biodiversidade , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Penicillium/isolamento & purificação , Portugal , Alga Marinha/microbiologia , Análise de Sequência de DNA , Tubulina (Proteína)/genética , Madeira/microbiologia
11.
Mycologia ; 111(3): 466-476, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31025901

RESUMO

Lasiodiplodia theobromae is a fungal plant pathogen that has been associated with Botryosphaeria dieback of grapevine. Despite several studies on L. theobromae, until now the production of secondary metabolites by strains isolated from grapevines has not been reported. The ability of two strains of L. theobromae isolated from grapevine to produce lipophilic metabolites was studied. Although many typical compounds of low molecular weight were identified from the crude extracts of both strains (e.g., lasiolactols, substituted 2-dihydrofuranones, melleins, jasmonic acid, 3-indolcarboxylic acid, botryodiplodins), (2R/2S,3S,4S)-3-epi-botryodiplodin was isolated for the first time as a natural compound. Furthermore, a comparative study of metabolite production was conducted at 25 and 37 C to understand temperature effects on metabolite profiles. Some metabolites were produced only by one strain (e.g., (3S,4S)-4-acetyl-3-methyl-2-dihydrofuranone produced by LA-SOL3) and others only at a specific temperature (e.g., jasmonic acid at 25 C, botryodiplodins at 37 C). Phytotoxicity and cytotoxicity of pure compounds were evaluated to clarify the influence of lipophilic metabolites on the biological activities of culture filtrates of both strains. The most toxic compound for Vero and 3T3 cells was (2R/2S,3S,4S)-3-epi-botryodiplodin.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Metabolismo Secundário , Temperatura , Vitis/microbiologia , Ascomicetos/química , Filogenia
12.
Mycologia ; 110(4): 642-653, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30062925

RESUMO

Lasiodiplodia theobromae is a phytopathogenic fungus that causes diseases not only in a broad number of plant hosts but also occasionally in humans. The capacity of L. theobromae to produce bioactive metabolites at 25 C (environmental mean temperature) and at 37 C (body mean temperature) was investigated. Two strains, CAA019 and CBS339.90, isolated respectively from a coconut tree and a human patient were characterized. The phytotoxicity and cytotoxicity (on mammalian cells) of the secretomes of both strains of L. theobromae were investigated. Also, phytotoxicity and cytotoxicity of pure compounds were evaluated. The phytotoxicity of the secretome of strain CAA019 was higher than the phytotoxicity of the secretome of strain CBS339.90 at 25 C. However, the phytotoxicity for both strains decreased when they were grown at 37 C. Only the secretome of strain CBS339.90 grown at 37 C induced up to 90% Vero and 3T3 cell mortality. This supports the presence of different metabolites in the secretome of strains CAA019 and CBS339.90. Metabolites typical of L. theobromae were isolated and identified from organic extracts of the secretome of both strains (e.g., 3-indolecarboxylic acid, jasmonic acid, lasiodiplodin, four substituted 2-dihydrofuranones, two melleins, and cyclo-(Trp-Ala)). Also, metabolites such as scytalone, not previously reported for this species, were isolated and identified. Metabolite production is affected by strain and temperature. In fact, some metabolites are strain specific (e.g., lasiodiplodin) and some metabolites are temperature specific (e.g., jasmonic acid). Although more strains should be characterized, it may be anticipated that temperature tuning of secondary-metabolite production emerges as a putative contributing factor in the modulation of L. theobromae pathogenicity towards plants, and also towards mammalian cells.


Assuntos
Ascomicetos/química , Ascomicetos/metabolismo , Metabolismo Secundário , Temperatura , Árvores/microbiologia , Animais , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Linhagem Celular , Chlorocebus aethiops , Cocos/microbiologia , Ciclopentanos/metabolismo , Ciclopentanos/toxicidade , Humanos , Metaboloma , Micotoxinas/biossíntese , Micotoxinas/metabolismo , Oxilipinas/metabolismo , Oxilipinas/toxicidade , Filogenia , Células Vero , Zearalenona/análogos & derivados , Zearalenona/metabolismo , Zearalenona/toxicidade
13.
Int J Mol Sci ; 19(2)2018 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-29360737

RESUMO

Phytopathogenic fungi are known to produce several types of enzymes usually involved in plant cell wall degradation and pathogenesis. The increasing of global temperature may induce fungi, such as Lasiodiplodia theobromae (L. theobromae), to alter its behavior. Nonetheless, there is only limited information regarding the effect of temperature on L. theobromae production of enzymes. The need for new, thermostable enzymes, that are biotechnologically relevant, led us to investigate the effect of temperature on the production of several extracellular enzymatic activities by different L. theobromae strains. Fungi were grown at 25 °C, 30 °C and 37 °C and the enzymatic activities were detected by plate assays, quantified by spectrophotometric methods and characterized by zymography. The thermostability (25-80 °C) of the enzymes produced was also tested. Strains CAA019, CBS339.90, LA-SOL3, LA-SV1 and LA-MA-1 produced amylases, gelatinases, caseinases, cellulases, lipases, laccases, xylanases, pectinases and pectin liases. Temperature modulated the expression of the enzymes, and this effect was more visible when fungi were grown at 37 °C than at lower temperatures. Contrary to proteolytic and endoglucanolytic activities, whose highest activities were detected when fungi were grown at 30 °C, lipolytic activity was not detected at this growth temperature. Profiles of proteases and endoglucanases of fungi grown at different temperatures were characterized by zymography. Enzymes were shown to be more thermostable when fungi were grown at 30 °C. Proteases were active up to 50 °C and endoglucanases up to 70 °C. Lipases were the least stable, with activities detected up to 45 °C. The enzymatic profiles detected for L. theobromae strains tested showed to be temperature and strain-dependent, making this species a good target for biotechnological applications.


Assuntos
Ascomicetos/metabolismo , Biotecnologia , Enzimas/biossíntese , Ascomicetos/enzimologia , Biotecnologia/métodos , Celulase , Ativação Enzimática , Ensaios Enzimáticos , Estabilidade Enzimática , Espaço Extracelular , Fermentação , Lipase , Peptídeo Hidrolases , Temperatura
14.
Front Plant Sci ; 7: 1096, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27536303

RESUMO

Environmental alterations modulate host-microorganism interactions. Little is known about how climate changes can trigger pathogenic features on symbiont or mutualistic microorganisms. Current climate models predict increased environmental temperatures. The exposing of phytopathogens to these changing conditions can have particularly relevant consequences for economically important species and for humans. The impact on pathogen/host interaction and the shift on their biogeographical range can induce different levels of virulence in new hosts, allowing massive losses in agricultural and health fields. Lasiodiplodia theobromae is a phytopathogenic fungus responsible for a number of diseases in various plants. It has also been described as an opportunist pathogen in humans, causing infections with different levels of severity. L. theobromae has a high capacity of adaptation to different environments, such as woody plants, moist argillaceous soils, or even humans, being able to grow and infect hosts in a wide range of temperatures (9-39°C). Nonetheless, the effect of an increase of temperature, as predicted in climate change models, on L. theobromae is unknown. Here we explore the effect of temperature on two strains of L. theobromae - an environmental strain, CAA019, and a clinical strain, CBS339.90. We show that both strains are cytotoxic to mammalian cells but while the environmental strain is cytotoxic mainly at 25°C, the clinical strain is cytotoxic mainly at 30 and 37°C. Extracellular gelatinolytic, xylanolytic, amylolytic, and cellulolytic activities at 25 and 37°C were characterized by zymography and the secretome of both strains grown at 25, 30, and 37°C were characterized by electrophoresis and by Orbitrap LC-MS/MS. More than 75% of the proteins were identified, mostly enzymes (glycosyl hydrolases and proteases). The strains showed different protein profiles, which were affected by growth temperature. Also, strain specific proteins were identified, such as a putative f5/8 type c domain protein - known for being involved in pathogenesis - by strain CAA019 and a putative tripeptidyl-peptidase 1 protein, by strain CBS339.90. We showed that temperature modulates the secretome of L. theobromae. This modulation may be associated with host-specificity requirements. We show that the study of abiotic factors, such as temperature, is crucial to understand host/pathogen interactions and its impact on disease.

15.
Proteomics ; 10(4): 873-87, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19953548

RESUMO

The growing interest in the application of proteomic technologies to solve toxicology issues and its relevance in ecotoxicology research has resulted in the emergence of "ecotoxicoproteomics". There is a general consensus that ecotoxicoproteomics is a powerful tool to spot early molecular events involved in toxicant responses, which are responsible for the adverse effects observed at higher levels of biological organization, thus contributing to elucidate the mode of action of stressors and to identify specific biomarkers. Ultimately, early-warning indicators can then be developed and deployed in "in situ" bioassays and in environmental risk assessment. The number of field experiments or laboratory trials using ecologically relevant test-species and involving proteomics has been, until recently, insufficient to allow a critical analysis of the real benefits of the application of this approach to ecotoxicology. This article intends to present an overview on the applications of proteomics in the context of ecotoxicology, focusing mainly on the prospective research to be done in invertebrates. Although these represent around 95% of all animal species and in spite of the key structural and functional roles they play in ecosystems, proteomic research in invertebrates is still in an incipient stage. We will review applications of ecotoxicoproteomics by evaluating the technical methods employed, the organisms and the contexts studied, the advances achieved until now and lastly the limitations yet to overcome will be discussed.


Assuntos
Ecotoxicologia , Invertebrados/fisiologia , Proteínas/análise , Proteômica/métodos , Animais , Monitoramento Ambiental , Modelos Animais , Proteínas/genética , Proteínas/metabolismo
16.
Small ; 3(7): 1230-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17534990

RESUMO

We report the synthesis of CdS quantum dot (QD)-poly(acrylate) nanocomposites using a recently developed catalytic system where activators are generated by electron transfer for atom-transfer radical polymerization (ATRP) in a miniemulsion. The QD surface was functionalized with a tris(alkyl)phosphine, previously modified with an ATRP chlorine initiator, and subsequent controlled polymerization was carried out from the functionalized surface of nanoparticles. The final material showed a high homogeneity and the QDs were evenly dispersed. The optical-absorption edge in the visible spectra of the nanocomposites attests the presence of the CdS QDs. Quantum confinement effects were assigned, though a blue shift in relation to the optical spectrum of the initial QDs has been observed.


Assuntos
Compostos de Cádmio , Nanocompostos , Polímeros , Pontos Quânticos , Sulfetos , Acrilatos/síntese química , Emulsões , Polímeros/síntese química
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