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1.
Microb Biotechnol ; 17(1): e14371, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38064205

RESUMO

Saprophytic fungi are able to catabolize many plant-derived aromatics, including, for example, gallate. The catabolism of gallate in fungi is assumed to depend on the five main central pathways, i.e., of the central intermediates' catechol, protocatechuate, hydroxyquinol, homogentisate and gentisate, but a definitive demonstration is lacking. To shed light on this process, we analysed the transcriptional reprogramming of the growth of Aspergillus terreus on gallate compared with acetate as the control condition. Surprisingly, the results revealed that the five main central pathways did not exhibit significant positive regulation. Instead, an in-depth analysis identified four highly expressed and upregulated genes that are part of a conserved gene cluster found in numerous species of fungi, though not in Aspergilli. The cluster comprises a monooxygenase gene and a fumarylacetoacetate hydrolase-like gene, which are recognized as key components of catabolic pathways responsible for aromatic compound degradation. The other two genes encode proteins with no reported enzymatic activities. Through functional analyses of gene deletion mutants in Aspergillus nidulans, the conserved short protein with no known domains could be linked to the conversion of the novel metabolite 5-hydroxydienelatone, whereas the DUF3500 gene likely encodes a ring-cleavage enzyme for 1,2,3,5-tetrahydroxybenzene. These significant findings establish the existence of a new 1,2,3,5-tetrahydroxybenzene central pathway for the catabolism of gallate and related compounds (e.g. 2,4,6-trihydroxybenzoate) in numerous fungi where this catabolic gene cluster was observed.


Assuntos
Fungos , Gentisatos , Fenóis , Fungos/genética
2.
Microbiol Spectr ; 11(4): e0066723, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37284774

RESUMO

Organic pollutants are omnipresent and can penetrate all environmental niches. We evaluated the hypothesis that short-term (acute) exposure to aromatic hydrocarbon pollutants could increase the potential for fungal virulence. Specifically, we analyzed whether pentachlorophenol and triclosan pollution results in the production of airborne fungal spores with greater virulence than those derived from an unpolluted (Control) condition. Each pollutant altered the composition of the community of airborne spores compared to the control, favoring an increase in strains with in vivo infection capacity (the wax moth Galleria mellonella was used as an infection model). Fungi subsisting inside larvae at 72 h postinjection with airborne spore inocula collected in polluted and unpolluted conditions exhibited comparable diversity (mainly within Aspergillus fumigatus). Several virulent Aspergillus strains were isolated from larvae infected with the airborne spores produced in a polluted environment. Meanwhile, strains isolated from larvae injected with spores from the control, including one A. fumigatus strain, showed no virulence. Potential pathogenicity increased when two Aspergillus virulent strains were assembled, suggesting the existence of synergisms that impact pathogenicity. None of the observed taxonomic or functional traits could separate the virulent from the avirulent strains. Our study emphasizes pollution stress as a possible driver of phenotypic adaptations that increase Aspergillus pathogenicity, as well as the need to better understand the interplay between pollution and fungal virulence. IMPORTANCE Fungi colonizing soil and organic pollutants often meet. The consequences of this encounter constitute an outstanding question. We scrutinized the potential for virulence of airborne fungal spores produced under unpolluted and polluted scenarios. The airborne spores showed increased diversity of strains with higher infection capacity in Galleria mellonella whenever pollution is present. Inside the larvae injected with either airborne spore community, the surviving fungi demonstrated a similar diversity, mainly within Aspergillus fumigatus. However, the isolated Aspergillus strains greatly differ since virulence was only observed for those associated with a polluted environment. The interplay between pollution and fungal virulence still hides many unresolved questions, but the encounter is costly: pollution stress promotes phenotypic adaptations that may increase Aspergillus pathogenicity.


Assuntos
Aspergilose , Poluentes Ambientais , Mariposas , Animais , Esporos Fúngicos , Aspergilose/microbiologia , Solo , Aspergillus fumigatus , Aspergillus , Mariposas/microbiologia , Larva/microbiologia
3.
Insects ; 14(6)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37367387

RESUMO

Anthonomus grandis Boheman (Coleoptera: Curculionidae) survives on alternative diets; however, this induces reproductive diapause. The objective was to evaluate the morphology and morphometry of the reproductive tract of this weevil after feeding on alternative diets. The experimental design was completely randomized with 160 replications and treatments arranged in a factorial design 3 × 3, represented by A. grandis adults fed on 3 food types (fragments of banana (T1) or orange (T2) endocarp, or with cotton squares of cultivar BRS 286 (T3, control)) and three evaluation periods (30, 60, and 90 days) and after each of these periods they were fed with cotton squares for 10 days. The reproductive tract of 100% of A. grandis females fed banana endocarp, orange endocarp, and cotton squares for 30 and 60 days and then cotton squares were morphologically adequate for reproduction, and after 90 days, only 50% of those fed cotton squares were in this condition. The length of the ovarioles and the width of the mature oocyte were greater for A. grandis fed on cotton squares and smaller in those with banana and orange endocarps. Histological sections reveal that male testes even with strong degenerative signals are already producing spermatozoa. On the other hand, females displayed ovaries with nurse cells in the tropharium and some maturing oocytes in the vitellarium. The body length was longer and the testis area and diameter smaller in males fed on cotton squares than in those with banana and orange endocarp. Anthonomus grandis females fed for ≥90 days with alternative food sources do not recover the functionality of their reproductive tract, even after consuming, for 10 days, a diet that favors reproduction. On the other hand, the males remain with their reproductive organs functional with this condition.

4.
Sci Total Environ ; 802: 149671, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34454147

RESUMO

The usage of reclaimed wastewater (RWW) for irrigation of agricultural soils is increasingly being acknowledged for reducing water consumption by promoting reuse of treated wastewater, and for the delivery of extant nutrients in the soil. The downside is that RWW may be a vector for contamination of soils with contaminants of emerging concern (CECs), if left uncontrolled. Its usage is anticipated to alter the soil properties, consequently also the soil microbial community. In the present study, soil microcosms were set to monitor how short periods (up to fourteen days) of RWW irrigation influence the soil ecosystem, namely its physicochemical properties, functioning, and colonising microbiota (differentiating fungi from bacteria). Two scenarios were studied: clean soil and soil contaminated (spiked) with 9 CECs, at conditions that limit any abiotic decay processes, monitoring along time fluctuations in the taxonomic and functional microbiota diversity. As shortly as fourteen days, the irrigation of either soil with RWW did not significantly (p > 0.05) alter its physicochemical properties and scarcely impacted the bioremediation processes of the CECs that showed decay levels ranging from 24% to 100%. Bacillus spp. dominance was enhanced along time in all the soil microcosms (reaching over 70% of the total abundance on the 7th day) but the RWW help to preserve, to some extent, high bacterial diversity. Besides, irrigation with RWW acted as a buffer of the soil mycobiota, limiting alterations in its composition caused either along time (to a minor degree) or due to contamination with CECs (to a great degree). This includes limiting the rise of Rhizopus sp. relative abundance. Collectively, our data support the utility of short-term periods of RWW irrigation for preserving the soil microbial diversity and functioning, especially when fungi are considered.


Assuntos
Microbiota , Águas Residuárias , Irrigação Agrícola , Solo , Microbiologia do Solo , Águas Residuárias/análise
5.
mBio ; 12(4): e0145821, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34372704

RESUMO

Aspergillus fumigatus is an important fungal pathogen and the main etiological agent of aspergillosis, a disease characterized by a noninvasive process that can evolve to a more severe clinical manifestation, called invasive pulmonary aspergillosis (IPA), in immunocompromised patients. The antifungal arsenal to threat aspergillosis is very restricted. Azoles are the main therapeutic approach to control IPA, but the emergence of azole-resistant A. fumigatus isolates has significantly increased over recent decades. Therefore, new strategies are necessary to combat aspergillosis, and drug repurposing has emerged as an efficient and alternative approach for identifying new antifungal drugs. Here, we used a screening approach to analyze A. fumigatus in vitro susceptibility to 1,127 compounds. A. fumigatus was susceptible to 10 compounds, including miltefosine, a drug that displayed fungicidal activity against A. fumigatus. By screening an A. fumigatus transcription factor null library, we identified a single mutant, which has the smiA (sensitive to miltefosine) gene deleted, conferring a phenotype of susceptibility to miltefosine. The transcriptional profiling (RNA-seq) of the wild-type and ΔsmiA strains and chromatin immunoprecipitation coupled to next-generation sequencing (ChIP-Seq) of an SmiA-tagged strain exposed to miltefosine revealed genes of the sphingolipid pathway that are directly or indirectly regulated by SmiA. Sphingolipid analysis demonstrated that the mutant has overall decreased levels of sphingolipids when growing in the presence of miltefosine. The identification of SmiA represents the first genetic element described and characterized that plays a direct role in miltefosine response in fungi. IMPORTANCE The filamentous fungus Aspergillus fumigatus causes a group of diseases named aspergillosis, and their development occurs after the inhalation of conidia dispersed in the environment. Very few classes of antifungal drugs are available for aspergillosis treatment, e.g., azoles, but the emergence of global resistance to azoles in A. fumigatus clinical isolates has increased over recent decades. Repositioning or repurposing drugs already available on the market is an interesting and faster opportunity for the identification of novel antifungal agents. By using a repurposing strategy, we identified 10 different compounds that impact A. fumigatus survival. One of these compounds, miltefosine, demonstrated fungicidal activity against A. fumigatus. The mechanism of action of miltefosine is unknown, and, aiming to get more insights about it, we identified a transcription factor, SmiA (sensitive to miltefosine), important for miltefosine resistance. Our results suggest that miltefosine displays antifungal activity against A. fumigatus, interfering in sphingolipid biosynthesis.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Ensaios de Triagem em Larga Escala , Fosforilcolina/análogos & derivados , Bibliotecas de Moléculas Pequenas/farmacologia , Esfingolipídeos/metabolismo , Animais , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Aspergillus fumigatus/química , Aspergillus fumigatus/patogenicidade , Farmacorresistência Fúngica , Larva/efeitos dos fármacos , Larva/microbiologia , Testes de Sensibilidade Microbiana , Mariposas/efeitos dos fármacos , Mariposas/microbiologia , Fenótipo , Fosforilcolina/farmacologia , Fosforilcolina/uso terapêutico , Virulência
6.
mSystems ; 6(1)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500329

RESUMO

In fungi, salicylate catabolism was believed to proceed only through the catechol branch of the 3-oxoadipate pathway, as shown, e.g., in Aspergillus nidulans However, the observation of a transient accumulation of gentisate upon the cultivation of Aspergillus terreus in salicylate medium questions this concept. To address this, we have run a comparative analysis of the transcriptome of these two species after growth in salicylate using acetate as a control condition. The results revealed the high complexity of the salicylate metabolism in A. terreus with the concomitant positive regulation of several pathways for the catabolism of aromatic compounds. This included the unexpected joint action of two pathways-3-hydroxyanthranilate and nicotinate-possibly crucial for the catabolism of aromatics in this fungus. Importantly, the 3-hydroxyanthranilate catabolic pathway in fungi is described here for the first time, whereas new genes participating in the nicotinate metabolism are also proposed. The transcriptome analysis showed also for the two species an intimate relationship between salicylate catabolism and secondary metabolism. This study emphasizes that the central pathways for the catabolism of aromatic hydrocarbons in fungi hold many mysteries yet to be discovered.IMPORTANCE Aspergilli are versatile cell factories used in industry for the production of organic acids, enzymes, and pharmaceutical drugs. To date, bio-based production of organic acids relies on food substrates. These processes are currently being challenged to switch to renewable nonfood raw materials-a reality that should inspire the use of lignin-derived aromatic monomers. In this context, aspergilli emerge at the forefront of future bio-based approaches due to their industrial relevance and recognized prolific catabolism of aromatic compounds. Notwithstanding considerable advances in the field, there are still important knowledge gaps in the central catabolism of aromatic hydrocarbons in fungi. Here, we disclose a novel central pathway, 3-hydroxyanthranilate, defying previously established ideas on the central metabolism of the aromatic amino acid tryptophan in Ascomycota We also observe that the catabolism of the aromatic salicylate greatly activated the secondary metabolism, furthering the significance of using lignin-derived aromatic hydrocarbons as a distinctive biomass source.

7.
Front Fungal Biol ; 2: 689900, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37744107

RESUMO

Invasive pulmonary aspergillosis is a life-threatening fungal infection especially in the immunocompromised patients. The low diversity of available antifungal drugs coupled with the emergence of antifungal resistance has become a worldwide clinical concern. The echinocandin Caspofungin (CSP) is recommended as a second-line therapy but resistance and tolerance mechanisms have been reported. However, how the fungal cell articulates the response to CSP is not completely understood. This work provides a detailed characterization of ZnfA, a transcription factor (TF) identified in previous screening studies that is involved in the A. fumigatus responses to calcium and CSP. This TF plays an important role in the regulation of iron homeostasis and cell wall organization in response to high CSP concentrations as revealed by Chromatin Immunoprecipitation coupled to DNA sequencing (ChIP-seq) analysis. Furthermore, ZnfA acts collaboratively with the key TF CrzA in modulating the response to calcium as well as cell wall and osmotic stresses. This study therefore describes the existence of an additional, previously unknown TF that bridges calcium signaling and the CSP cellular response and further exposes the complex connections that exist among different pathways which govern stress sensing and signaling in A. fumigatus.

8.
Microb Biotechnol ; 13(6): 1983-1996, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32813320

RESUMO

Hydroxymethylfurfural (HMF) is a promising lignocellulosic-derived source for the generation of diverse chemical building blocks constituting an alternative to fossil fuels. However, it remains unanswered if ubiquitous fungi can ensure their efficient decay, similar to that observed in highly specialised fungi. To disclose the genetic basis of HMF degradation in aspergilli, we performed a comprehensive analysis of Aspergillus nidulans ability to tolerate and to degrade HMF and its derivatives (including an HMF-dimer). We identified the degradation pathway using a suite of metabolomics methods and showed that HMF was modified throughout sequential reactions, ultimately yielding derivatives subsequently channelled to the TCA cycle. Based on the previously revealed hmfFGH gene cluster of Cupriavidus basilensis, we combined gene expression of homologous genes in Aspergillus nidulans and functional analyses in single-deletion mutants. Results were complemented with orthology analyses across the genomes of twenty-five fungal species. Our results support high functional redundancy for the initial steps of the HMF degradation pathway in the majority of the analysed fungal genomes and the assignment of a single-copy furan-2,5-dicarboxylic acid decarboxylase gene in A. nidulans. Collectively our data made apparent the superior capacity of aspergilli to mineralise HMF, furthering the environmental sustainability of a furan-based chemistry.


Assuntos
Aspergillus nidulans , Aspergillus nidulans/genética , Cupriavidus , Furaldeído/análogos & derivados , Furanos
9.
Adv Microb Physiol ; 75: 177-203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31655737

RESUMO

The diversity and abundance of aromatic compounds in nature is crucial for proper metabolism in all biological systems, and also impacts greatly the development of many industrial processes. Naturally, understanding their catabolism becomes fundamental for many scientific fields of research, from clinical and environmental to technological. The genetic basis of the central pathways for the catabolism of aromatic compounds in fungi, particularly of benzene derivatives, remains however poorly understood largely overlooking their significance. In some Dikarya species the genes of the central pathways are clustered in the genome, often in an array with peripheral pathway genes, even if the existence of a specific pathway does not necessarily mean that the composing genes are clustered. The current availability of many annotated fungal genomes in the postgenomic era creates conditions to reach a more holistic view of these processes through target analysis of the central pathways gene clusters. Inspired by this, we have critically analyzed the established biochemical and genetic data on the catabolism of aromatic compounds in Dikarya after dissecting the presence and distribution of central catabolic gene clusters (at times including also details on gene diversity, order and orientation) and of peripheral genes. Our methodological approach illustrates the multiple degrees of separation in these central pathways gene clusters across Dikarya. Surprisingly, they show a great degree of similarity irrespectively of the Dikarya division, emphasizing that knowledge established on either phyla can guide the identification of clusters of comparable composition (in-cluster plus peripheral genes) in uncharacterized species.


Assuntos
Fungos/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/classificação , Fungos/genética , Hidrocarbonetos Aromáticos/química , Família Multigênica , Filogenia
10.
Evol Appl ; 12(6): 1164-1177, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31293629

RESUMO

Habitat degradation and climate change are currently threatening wild pollinators, compromising their ability to provide pollination services to wild and cultivated plants. Landscape genomics offers powerful tools to assess the influence of landscape modifications on genetic diversity and functional connectivity, and to identify adaptations to local environmental conditions that could facilitate future bee survival. Here, we assessed range-wide patterns of genetic structure, genetic diversity, gene flow, and local adaptation in the stingless bee Melipona subnitida, a tropical pollinator of key biological and economic importance inhabiting one of the driest and hottest regions of South America. Our results reveal four genetic clusters across the species' full distribution range. All populations were found to be under a mutation-drift equilibrium, and genetic diversity was not influenced by the amount of reminiscent natural habitats. However, genetic relatedness was spatially autocorrelated and isolation by landscape resistance explained range-wide relatedness patterns better than isolation by geographic distance, contradicting earlier findings for stingless bees. Specifically, gene flow was enhanced by increased thermal stability, higher forest cover, lower elevations, and less corrugated terrains. Finally, we detected genomic signatures of adaptation to temperature, precipitation, and forest cover, spatially distributed in latitudinal and altitudinal patterns. Taken together, our findings shed important light on the life history of M. subnitida and highlight the role of regions with large thermal fluctuations, deforested areas, and mountain ranges as dispersal barriers. Conservation actions such as restricting long-distance colony transportation, preserving local adaptations, and improving the connectivity between highlands and lowlands are likely to assure future pollination services.

11.
Microbiome ; 6(1): 208, 2018 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-30466483

RESUMO

BACKGROUND: The impacts of man-made chemicals, in particular of persistent organic pollutants, are multifactorial as they may affect the integrity of ecosystems, alter biodiversity and have undesirable effects on many organisms. We have previously demonstrated that the belowground mycobiota of forest soils acts as a buffer against the biocide pollutant pentachlorophenol. However, the trade-offs made by mycobiota to mitigate this pollutant remain cryptic. RESULTS: Herein, we demonstrate using a culture-dependent approach that exposure to pentachlorophenol led to alterations in the composition and functioning of the metacommunity, many of which were not fully alleviated when most of the biocide was degraded. Proteomic and physiological analyses showed that the carbon and nitrogen metabolisms were particularly affected. This dysregulation is possibly linked to the higher pathogenic potential of the metacommunity following exposure to the biocide, supported by the secretion of proteins related to pathogenicity and reduced susceptibility to a fungicide. Our findings provide additional evidence for the silent risks of environmental pollution, particularly as it may favour the development of pathogenic trade-offs in fungi, which may impose serious threats to animals and plant hosts.


Assuntos
Poluentes Ambientais/toxicidade , Poluição Ambiental/análise , Fungos/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Pentaclorofenol/toxicidade , Esporos Fúngicos/crescimento & desenvolvimento , Carbono/metabolismo , Florestas , Fungos/genética , Fungos/metabolismo , Nitrogênio/metabolismo , Proteoma/genética
12.
J Ethnobiol Ethnomed ; 14(1): 47, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005687

RESUMO

BACKGROUND: According to the biophilia hypothesis, an emotional affiliation with nature has been inherited during human biocultural evolution. Research on beekeeping can contribute to the scientific understanding of the influence of emotions in the human-nature relationship, since this activity provides concrete experiences of beneficial interaction between the human being and the environment by stimulating conservation-friendly values among practitioners. In this study, we investigated motivations and preferences driving beekeepers' choices. We hypothesized that emotional criteria would be the main motivators in choosing to include beekeeping into small-scale farming systems. We also assumed that, once beekeeping has been chosen, the preference among species of bees for raising would also be influenced mainly by emotional criteria. METHODS: Data were collected from free lists and semi-structured interviews with 52 keepers of stingless bees from Sítio Xixá in the state of Pernambuco, Brazil. The content analysis technique was used to analyze data from interviews. The underlying criteria for motivation and preference quoted in the free lists were analyzed with Smith's Salience Index. RESULTS: Emotional and esthetic criteria were the most salient motivations for choosing beekeeping as one of the activities in small-scale farming systems. On the other hand, honey productivity and bee behavior were the most salient criteria for the preference for certain bee species to be kept. CONCLUSIONS: Emotional criterion had an especially notable influence on the motives for practicing beekeeping, but not on the preference of species to be raised. This demonstrates that the scenario under study represents a panorama of multiple influences in which emotions are one, but not the only, important component. Finally, our results indicate that the emotional domain should be taken into account in environmental education efforts and in the planning of bee management and nature conservation policies.


Assuntos
Criação de Abelhas , Comportamento de Escolha , Emoções , Motivação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Biota Neotrop. (Online, Ed. ingl.) ; 18(2): e20170410, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951169

RESUMO

Abstract: In detritus-based trophic systems, springtails, dung beetles, saprophagous calyptrate flies and termites consume and fragment organic matter and control populations of decomposer microorganisms, exerting a strong influence on energy and nutrient fluxes. A faunal inventory of these four groups of hexapods was performed in Serra de Santa Catarina (SSC), an area of arboreal-shrub caatinga located in the state of Paraíba, with the purpose of characterizing the assemblages of these taxa, and highlighting their unique links to the local ecosystem. Samplings were performed in May, 2014, and April, 2015, both during the rainy season. Standard sampling protocols for biodiversity inventory of the various taxa were used, including both active and passive sampling methods. In general, 114 species of hexapods were captured, with 26 species of springtails, 20 dung beetles, 30 saprophagous calyptrate flies and 38 termites, with sampling sufficiency varying from 69.5 to 96.8% of total estimated richness. Species richness of the groups are among the highest recorded for a single area of Caatinga, with some taxa being recorded for the first time for the domain. Several morphospecies had indeterminate taxonomic status, especially springtails and termites, and are quite likely new species to science. The structure of the assemblages of springtails, dung beetles, saprophagous calyptrate flies and termites recorded in SSC, suggest that this conserved area is unique within the highly impacted landscape of Caatinga, and has great potential for the conservation of biodiversity of this domain in the Northeast Region of Brazil.


Resumo: No sistema trófico baseado em detritos, os colêmbolos, besouros escarabeíneos, moscas saprófagas e térmitas atuam no consumo e fragmentação da matéria orgânica e no controle das populações de microrganismos decompositores, exercendo forte influência nos fluxos de energia e nutrientes. Um inventário faunístico desses quatro grupos de hexápodes foi realizado na Serra de Santa Catarina (SSC), uma área de Caatinga arbóreo-arbustiva localizada no Estado da Paraiba, com intuito de caracterizar as taxocenoses desses táxons, salientando as suas peculiaridades ligadas ao ecossistema local. As coletas foram realizadas em maio/2014 e abril/2015, durante o período chuvoso na região. De acordo com o táxon, foram utilizados protocolos amostrais padronizados para inventários de biodiversidade, com métodos passivos e ativos de coleta. No geral, 114 espécies de hexápodes foram capturadas, sendo 26 de colêmbolos, 20 de besouros escarabeíneos, 30 de dípteros e 38 de térmitas, com suficiência amostral variando de 69,5 a 96.8% da total estimada. A riqueza de espécies por grupo está entre as maiores para uma única área de Caatinga, com alguns táxons sendo registrados pela primeira vez para o domínio. Especialmente para os colêmbolos e térmitas, várias morfoespécies tiveram seus status taxonômicos indeterminados, havendo elevada possibilidade de serem nova para a ciência. As estruturas e funcionalidades das taxocenoses de colêmbolos, besouros escarabeíneos, moscas saprófagas e térmitas registradas na SSC, sugerem que esse ecossistema é singular, dentro de um cenário generalizado de impacto antrópico presente na Caatinga, e possui um elevado potencial para a conservação da biodiversidade desse domínio no nordeste brasileiro.

14.
Ecotoxicology ; 26(9): 1157-1169, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28828683

RESUMO

Metal contamination is still a major environmental issue due to their continuous deposition and persistence. In this work we intended to assess the impact that Copper (Cu) and Zinc (Zn) exert in life-history parameters of Daphnia longispina, a common cladoceran in freshwater environments. Thus, we studied the effects of Cu (20-300 µg/L) and Zn (500-4000 µg/L) on the survival, growth, reproduction, feeding rate and population growth rate of D. longispina. Though survival was only reduced for the highest concentration of each metal, other endpoints were strongly affected by lower concentrations. Growth was affected by both metals, especially in the period 0-7 d, being significant for Cu ≥ 40 µg/L and Zn ≥ 500 µg/L. Indeed, growth endpoints at day 7 (body length and growth rate) were equally or more sensitive than the corresponding endpoints at day 21. The size at first reproduction decreased (significant for Cu ≥ 40 µg/L and Zn ≥ 500 µg/L). Reproduction decreased, which was partially explained by the reduced growth, but additional effects were supported by a direct effect of metals on reproduction (based on the relationship body length-brood size). Reduced growth and reproduction are likely a food mediated effect due to feeding inhibition caused by the metals. Globally, the studied endpoints were affected by Cu and Zn differently, supporting a chemical-specificity of the effects, with Zn causing more pronounced effects than Cu. This work presents an innovative approach to the effects of Cu and Zn to D. longispina, giving a general and comprehensive overview of those effects.


Assuntos
Cobre/toxicidade , Daphnia/fisiologia , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Animais , Daphnia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estágios do Ciclo de Vida/efeitos dos fármacos , Reprodução/efeitos dos fármacos
15.
Curr Opin Microbiol ; 37: 142-149, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28704686

RESUMO

Atmospheric release of persistent organic pollutants (POPs) constitutes a silent threat through chronic contamination of soils at global scale; yet fundamental understanding of their occurrence, sources and fate is still largely lacking. Similar to a three act play, this review comprises Setup, Confrontation and Resolution. The first emphasises the eighty years of the history of pentachlorophenol (PCP) usage, only recently classified as POP. The second focus on active sources of PCP pollution, including inside cork oak forests in N.W. Tunisia; a threat partially neutralised by the soil microbial diversity, especially fungi. As Resolution, the need for improved knowledge on the global distribution and impacts of PCP in soil microbial diversity as means to preserve the multi-functionality of terrestrial ecosystem is emphasised.


Assuntos
Antifúngicos/metabolismo , Poluentes Ambientais/metabolismo , Fungos/efeitos dos fármacos , Micobioma/efeitos dos fármacos , Pentaclorofenol/metabolismo , Quercus/crescimento & desenvolvimento , Microbiologia do Solo , Florestas , Tunísia
16.
PLoS One ; 12(4): e0175725, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28410408

RESUMO

Partamona seridoensis is an endemic stingless bee from the Caatinga, a Neotropical dry forest in northeastern Brazil. Like other stingless bees, this species plays an important ecological role as a pollinator. The aim of the present study was to investigate the genetic structure and evolutionary history of P. seridoensis across its current geographic range. Workers from 84 nests from 17 localities were analyzed for COI and Cytb genic regions. The population structure tests (Bayesian phylogenetic inference, AMOVA and haplotype network) consistently characterized two haplogroups (northwestern and eastern), with little gene flow between them, generating a high differentiation between them as well as among the populations within each haplogroup. The Mantel test revealed no isolation by distance. No evidence of a potential geographic barrier in the present that could explain the diversification between the P. seridoensis haplogroups was found. However, Pleistocene climatic changes may explain this differentiation, since the initial time for the P. seridoensis lineages diversification took place during the mid-Pleistocene, specifically the interglacial period, when the biota is presumed to have been more associated with dry conditions and had more restricted, fragmented geographical distribution. This event may have driven diversification by isolating the two haplogroups. Otherwise, the climatic changes in the late Pleistocene must not have drastically affected the population dynamics of P. seridoensis, since the Bayesian Skyline Plot did not reveal any substantial fluctuation in effective population size in either haplogroup. Considering its importance and the fact that it is an endemic bee from a very threatened Neotropical dry forest, the results herein could be useful to the development of conservation strategies for P. seridoensis.


Assuntos
Abelhas/genética , Mudança Climática , Animais , Teorema de Bayes , Abelhas/classificação , Evolução Biológica , DNA Mitocondrial/química , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Florestas , Fluxo Gênico , Variação Genética , Haplótipos , Filogenia , Filogeografia , Dinâmica Populacional , Análise de Sequência de DNA
17.
Springerplus ; 4: 382, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26240780

RESUMO

BACKGROUND: The search for new antimicrobial compounds able to overcome the global issue of microbial resistance to antibiotics is a priority worldwide. Moreover, several commensal microorganisms have been increasingly associated to opportunistic microbial infections. Having previously disclosed the green synthesis and preliminary characterization of the oligomers [linear oligo(ethylenimine) hydrochloride and oligo(2-methyl-2-oxazoline) quaternized with N,N-dimethyldodecylamine] we herein report on the screening of these oligomers against a battery of 69 clinical isolates of Aerococcus spp., Candida spp., Staphylococcus spp. and Streptococcus spp. FINDINGS: The isolates' susceptibility to both oligomers was evaluated by determining their minimal inhibitory concentration (MIC) and the biocidal effectiveness of each compound was further confirmed through spectrophotometric measurements and fluorescence microscopy. The MIC values of the 69 isolates were highly variable, yet favourably comparable with those of other antimicrobial polymers. The viability assays resulted in 100% of microbial killing rate after only 5 min, highlighting the promising antimicrobial action of these oligomers. CONCLUSIONS: Though further studies are required, evidence suggests that a strong effort should be done in order to confirm these compounds as valid alternatives for several clinical applications. This is reinforced by their well described biocompatibility with human tissues and by their proposed mechanism of action which difficult the development of microbial resistance to these compounds.

18.
Environ Microbiol ; 17(8): 2922-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25753337

RESUMO

Pentachlorophenol (PCP) is globally dispersed and contamination of soil with this biocide adversely affects its functional biodiversity, particularly of fungi - key colonizers. Their functional role as a community is poorly understood, although a few pathways have been already elucidated in pure cultures. This constitutes here our main challenge - elucidate how fungi influence the pollutant mitigation processes in forest soils. Circumstantial evidence exists that cork oak forests in N. W. Tunisia - economically critical managed forests are likely to be contaminated with PCP, but the scientific evidence has previously been lacking. Our data illustrate significant forest contamination through the detection of undefined active sources of PCP. By solving the taxonomic diversity and the PCP-derived metabolomes of both the cultivable fungi and the fungal community, we demonstrate here that most strains (predominantly penicillia) participate in the pollutant biotic degradation. They form an array of degradation intermediates and by-products, including several hydroquinone, resorcinol and catechol derivatives, either chlorinated or not. The degradation pathway of the fungal community includes uncharacterized derivatives, e.g. tetrachloroguaiacol isomers. Our study highlights fungi key role in the mineralization and short lifetime of PCP in forest soils and provide novel tools to monitor its degradation in other fungi dominated food webs.


Assuntos
Florestas , Fungos/metabolismo , Pentaclorofenol/metabolismo , Quercus/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biodiversidade , Poluição Ambiental , Fungos/isolamento & purificação , Solo/química , Tunísia
19.
BMC Genomics ; 15: 613, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25043916

RESUMO

BACKGROUND: Lipid polymers in plant cell walls, such as cutin and suberin, build recalcitrant hydrophobic protective barriers. Their degradation is of foremost importance for both plant pathogenic and saprophytic fungi. Regardless of numerous reports on fungal degradation of emulsified fatty acids or cutin, and on fungi-plant interactions, the pathways involved in the degradation and utilisation of suberin remain largely overlooked. As a structural component of the plant cell wall, suberin isolation, in general, uses harsh depolymerisation methods that destroy its macromolecular structure. We recently overcame this limitation isolating suberin macromolecules in a near-native state. RESULTS: Suberin macromolecules were used here to analyse the pathways involved in suberin degradation and utilisation by Aspergillus nidulans. Whole-genome profiling data revealed the complex degrading enzymatic machinery used by this saprophytic fungus. Initial suberin modification involved ester hydrolysis and ω-hydroxy fatty acid oxidation that released long chain fatty acids. These fatty acids were processed through peroxisomal ß-oxidation, leading to up-regulation of genes encoding the major enzymes of these pathways (e.g. faaB and aoxA). The obtained transcriptome data was further complemented by secretome, microscopic and spectroscopic analyses. CONCLUSIONS: Data support that during fungal growth on suberin, cutinase 1 and some lipases (e.g. AN8046) acted as the major suberin degrading enzymes (regulated by FarA and possibly by some unknown regulatory elements). Suberin also induced the onset of sexual development and the boost of secondary metabolism.


Assuntos
Aspergillus nidulans/genética , Carbono/metabolismo , Lipídeos/química , Aspergillus nidulans/enzimologia , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/metabolismo , Ácidos Graxos/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genoma Fúngico , Lipase/genética , Lipase/metabolismo , Oxirredução , Poliésteres/química , Poliésteres/metabolismo , Transcriptoma
20.
Rev. adm. saúde ; 16(63): 61-66, abr.-maio 2014.
Artigo em Português | LILACS | ID: lil-771428

RESUMO

Nos últimos anos, o desenvolvimento da tecnologia tem modificado a sociedade em todos os setores. Na área da saúde, especificamente a informática tem contribuído de forma significativa, proporcionando resultados favoráveis para profissionais da saúde, usuários e gestão. Este estudo, de caráter exploratório descritivo, pautado em pesquisa bibliográfica, analisando artigos, teses e dissertações, pretende verificar e avaliar a contribuição da implantação de prontuário eletrônico do paciente (PEP), identificando suas vantagens e desvantagens para a instituição de saúde. Pode-se concluir que, embora haja necessidade de um grande investimento inicial na implantação do prontuário eletrônico, no decorrer do tempo a implantação do PEP pode se traduzir em vantagens para a gestão hospitalar.


In recent years, the development of technology has changed the society in all sectors. In the health area, specifically information technology has contributed significantly, providing favorable results for health professionals, users and administration. This study, a descriptive exploratory one, based on literature review, analyzes articles, theses and dissertations to assess and evaluate the contribution of the implementationof electronic health record, and to identify its advantages and disadvantages for health institution. It can be concluded that although there is need for a large initial investment in the implementation of electronic health record, over time its implementation can be translated into advantages for hospital administration.


Assuntos
Humanos , Masculino , Feminino , Sistemas de Informação em Atendimento Ambulatorial , Eficiência , Registros de Saúde Pessoal , Projetos de Tecnologias de Informação e Comunicação , Sistemas de Registro de Ordens Médicas , Sistemas Computadorizados de Registros Médicos , Pessoal de Saúde , Política Pública , Gestão da Qualidade Total
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