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1.
iScience ; 26(8): 107276, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37559905

RESUMO

Globally, human activities impose threats to nature and the provision of ecosystem services, such as pollination. In this context, ecological restoration provides opportunities to create managed landscapes that maximize biodiversity conservation and sustainable agriculture, e.g., via provision of pollination services. Managing pollination services and restoration opportunities requires the engagement of distinct stakeholders embedded in diverse social institutions. Nevertheless, frameworks toward sustainable agriculture often overlook how stakeholders interact and access power in social arenas. We present a perspective integrating pollination services, ecological restoration, and public engagement for biodiversity conservation and agricultural production. We highlight the importance of a comprehensive assessment of pollination services, restoration opportunities identification, and a public engagement strategy anchored in institutional analysis of the social arenas involved in restoration efforts. Our perspective can therefore guide the implementation of practices from local to country scales to enhance biodiversity conservation and sustainable agriculture.

2.
Gigascience ; 112022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35639882

RESUMO

BACKGROUND: Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. RESULTS: Here we present a vocabulary of terms and a data model for sharing plant-pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant-pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant-pollinator interactions. CONCLUSIONS: The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant-pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant-pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of terms.


Assuntos
Ecossistema , Polinização , Animais , Biodiversidade , Filogenia , Padrões de Referência
4.
Insects ; 12(9)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34564206

RESUMO

Although the quality of citizen science (CS) data is often a concern, evidence for high-quality CS data increases in the scientific literature. This study aimed to assess the data reliability of a structured CS protocol for monitoring stingless bees' flight activity. We tested (1) data accuracy for replication among volunteers and for expert validation and (2) precision, comparing dispersion between citizen scientists and expert data. Two distinct activity dimensions were considered: (a) perception of flight activity and (b) flight activity counts (entrances, exits, and pollen load). No significant differences were found among groups regarding entrances and exits. However, replicator citizen scientists presented a higher chance of perceiving pollen than original data collectors and experts, likely a false positive. For those videos in which there was an agreement about pollen presence, the effective pollen counts were similar (with higher dispersion for citizen scientists), indicating the reliability of CS-collected data. The quality of the videos, a potential source of variance, did not influence the results. Increasing practical training could be an alternative to improve pollen data quality. Our study shows that CS provides reliable data for monitoring bee activity and highlights the relevance of a multi-dimensional approach for assessing CS data quality.

5.
Environ Sci Technol ; 55(17): 12043-12053, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34423633

RESUMO

Crop pollination is one of Nature's Contributions to People (NCP) that reconciles biodiversity conservation and agricultural production. NCP benefits vary across space, including among distinct political-administrative levels within nations. Moreover, initiatives to restore ecosystems may enhance NCP provision, such as crop pollination delivered by native pollinators. We mapped crop pollination demand (PD), diversity of pollinator-dependent crops, and vegetation deficit (VD) (vis-a-vis Brazilian legal requirements) across all 5570 municipalities in Brazil. Pollinator-dependent crops represented ∼55% of the annual monetary value of agricultural production and ∼15% of the annual crop production. Municipalities with greater crop PD (i.e., higher degree of pollinator dependence of crop production) also had greater VD, associated with large properties and monocultures. In contrast, municipalities with a greater diversity of pollinator-dependent crops and predominantly small properties presented a smaller VD. Our results support that ecological restoration prompted by legal requirements offers great potential to promote crop productivity in larger properties. Moreover, conservation of vegetation remnants could support food security in small properties. We provided the first steps to identify spatial patterns linking biodiversity conservation and pollination service. Using Brazilian legal requirements as an example, we show that land-use management policies may be successfully used to ensure agricultural sustainability and crop production.


Assuntos
Ecossistema , Polinização , Agricultura , Abelhas , Biodiversidade , Brasil , Produtos Agrícolas , Humanos
6.
Ecology ; 102(8): e03377, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33937987

RESUMO

Bees are a diverse group of insects that have tremendous importance as pollinators. In recent decades, there has been a global decline in bee populations because of land-use change, intensive agriculture, and climate change. Unfortunately, our knowledge of native bees' ecology is rather scarce, and such knowledge gaps are also a major threat to its conservation. In this sense, biological collections are a priceless natural history legacy and an information source for new research and decision making. Chile has a remarkable bee diversity, with 464 species currently known from Chile and a high incidence of endemism and a variety of habitats (including the Mediterranean biodiversity hotspot). The largest wild bee collection in Chile is held at the Pontificia Universidad Católica de Valparaíso (comprising a century of data). This collection has been recently included in GBIF. Here we present a database with 36,010 records, including information on sociality and ecology (including information on floral visitation range, the resource collected, and nesting substrates) for 160 out of the 167 bee species included (36% of the Chilean bee diversity, including 49 genera and five families). All records have the taxonomy resolved, and 83% of them have geographic coordinates, covering a latitudinal range between 18° S and 53° S from the continental and insular territories. This data set is released for noncommercial use only. Credits should be given to this paper (i.e., proper citation), and the products generated with this database should be shared under the same license terms (CC BY-NC-SA).

7.
Artif Organs ; 44(7): E288-E299, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31950507

RESUMO

Human adipose stem/stromal cell (ASC) spheroids were used as a serum-free in vitro model to recapitulate the molecular events and extracellular matrix organization that orchestrate a hypertrophic cartilage phenotype. Induced-ASC spheroids (ø = 450 µm) showed high cell viability throughout the period of culture. The expression of collagen type X alpha 1 chain (COLXA1) and matrix metallopeptidase 13 (MMP-13) was upregulated at week 2 in induced-ASC spheroids compared with week 5 (P < .001) evaluated by quantitative real-time PCR. In accordance, secreted levels of IL-6 (P < .0001), IL-8 (P < .0001), IL-10 (P < .0001), bFGF (P < .001), VEGF (P < .0001), and RANTES (P < .0001) were the highest at week 2. Strong in situ staining for collagen type X and low staining for TSP-1 was associated with the increase of hypertrophic genes expression at week 2 in induced-ASC spheroids. Collagen type I, osteocalcin, biglycan, and tenascin C were detected at week 5 by in situ staining, in accordance with the highest expression of alkaline phosphatase (ALPL) gene and the presence of calcium deposits as evaluated by Alizarin Red O staining. Induced-ASC spheroids showed a higher force required to compression at week 2 (P < .0001). The human ASC spheroids under serum-free inducer medium and normoxic culture conditions were induced to a hypertrophic cartilage phenotype, opening a new perspective to recapitulate endochondral ossification in vivo.


Assuntos
Cartilagem/crescimento & desenvolvimento , Condrogênese/fisiologia , Células-Tronco Mesenquimais/fisiologia , Cultura Primária de Células/métodos , Engenharia Tecidual/métodos , Tecido Adiposo/citologia , Cartilagem/citologia , Cartilagem/ultraestrutura , Diferenciação Celular/fisiologia , Células Cultivadas , Colágeno Tipo X/metabolismo , Meios de Cultura Livres de Soro , Matriz Extracelular/metabolismo , Humanos , Hipertrofia , Metaloproteinase 13 da Matriz/metabolismo , Microscopia Eletrônica de Transmissão , Esferoides Celulares/fisiologia , Esferoides Celulares/ultraestrutura , Células Estromais/fisiologia
8.
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.

9.
Front Microbiol ; 8: 2512, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312213

RESUMO

Escherichia coli is an important microorganism in the gastrointestinal tract of warm-blooded animals. Commensal populations of E. coli consist of stable genetic isolates, which means that each individual has only one phylogenetic group (phylogroup). We evaluated the frequency of human commensal E. coli phylogroups from 116 people and observed that the majority of isolates belonged to group A. We also evaluated the frequency of phylogroups in wastewater samples and found a strong positive correlation between the phylogroup distribution in wastewater and human hosts. In order to find out if some factors, such as geographical location, and climate could influence the worldwide phylogroup distribution, we performed a meta-analysis of 39 different studies and 24 countries, including different climates, living areas, and feeding habits. Unexpectedly, our results showed no substructuring patterns of phylogroups; indicating there was no correlation between phylogroup distribution and geographic location, climate, living area, feeding habits, or date of collection.

10.
PLoS One ; 11(2): e0148295, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26882479

RESUMO

The ecological impacts of alien species invasion are a major threat to global biodiversity. The increasing number of invasion events by alien species and the high cost and difficulty of eradicating invasive species once established require the development of new methods and tools for predicting the most susceptible areas to invasion. Invasive pollinators pose serious threats to biodiversity and human activity due to their close relationship with many plants (including crop species) and high potential competitiveness for resources with native pollinators. Although at an early stage of expansion, the bumblebee species Bombus terrestris is becoming a representative case of pollinator invasion at a global scale, particularly given its high velocity of invasive spread and the increasing number of reports of its impacts on native bees and crops in many countries. We present here a methodological framework of habitat suitability modeling that integrates new approaches for detecting habitats that are susceptible to Bombus terrestris invasion at a global scale. Our approach did not include reported invaded locations in the modeling procedure; instead, those locations were used exclusively to evaluate the accuracy of the models in predicting suitability over regions already invaded. Moreover, a new and more intuitive approach was developed to select the models and evaluate different algorithms based on their performance and predictive convergence. Finally, we present a comprehensive global map of susceptibility to Bombus terrestris invasion that highlights priority areas for monitoring.


Assuntos
Distribuição Animal/fisiologia , Abelhas/fisiologia , Comportamento Competitivo/fisiologia , Espécies Introduzidas , Modelos Estatísticos , Polinização/fisiologia , Animais , Clima , Europa (Continente) , Japão , América Latina , Nova Zelândia , Filogeografia
11.
Science ; 351(6271): 388-91, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26798016

RESUMO

Ecological intensification, or the improvement of crop yield through enhancement of biodiversity, may be a sustainable pathway toward greater food supplies. Such sustainable increases may be especially important for the 2 billion people reliant on small farms, many of which are undernourished, yet we know little about the efficacy of this approach. Using a coordinated protocol across regions and crops, we quantify to what degree enhancing pollinator density and richness can improve yields on 344 fields from 33 pollinator-dependent crop systems in small and large farms from Africa, Asia, and Latin America. For fields less than 2 hectares, we found that yield gaps could be closed by a median of 24% through higher flower-visitor density. For larger fields, such benefits only occurred at high flower-visitor richness. Worldwide, our study demonstrates that ecological intensification can create synchronous biodiversity and yield outcomes.


Assuntos
Abelhas , Biodiversidade , Produção Agrícola , Produtos Agrícolas/crescimento & desenvolvimento , Polinização , África , Animais , Ásia , Flores/crescimento & desenvolvimento
12.
PLoS One ; 10(9): e0137198, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26356234

RESUMO

Supergeneralists, defined as species that interact with multiple groups of species in ecological networks, can act as important connectors of otherwise disconnected species subsets. In Brazil, there are two supergeneralist bees: the honeybee Apis mellifera, a non-native species, and Trigona spinipes, a native stingless bee. We compared the role of both species and the effect of geographic and local factors on networks by addressing three questions: 1) Do both species have similar abundance and interaction patterns (degree and strength) in plant-bee networks? 2) Are both species equally influential to the network structure (nestedness, connectance, and plant and bee niche overlap)? 3) How are these species affected by geographic (altitude, temperature, precipitation) and local (natural vs. disturbed habitat) factors? We analyzed 21 plant-bee weighted interaction networks, encompassing most of the main biomes in Brazil. We found no significant difference between both species in abundance, in the number of plant species with which each bee species interacts (degree), and in the sum of their dependencies (strength). Structural equation models revealed the effect of A. mellifera and T. spinipes, respectively, on the interaction network pattern (nestedness) and in the similarity in bee's interactive partners (bee niche overlap). It is most likely that the recent invasion of A. mellifera resulted in its rapid settlement inside the core of species that retain the largest number of interactions, resulting in a strong influence on nestedness. However, the long-term interaction between native T. spinipes and other bees most likely has a more direct effect on their interactive behavior. Moreover, temperature negatively affected A. mellifera bees, whereas disturbed habitats positively affected T. spinipes. Conversely, precipitation showed no effect. Being positively (T. spinipes) or indifferently (A. mellifera) affected by disturbed habitats makes these species prone to pollinate plant species in these areas, which are potentially poor in pollinators.


Assuntos
Abelhas/fisiologia , Ecossistema , Plantas , Animais , Brasil , Geografia , Modelos Teóricos , Especificidade da Espécie , Temperatura
13.
PLoS One ; 10(6): e0129225, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26091014

RESUMO

Ecosystem services provided by mobile agents are increasingly threatened by the loss and modification of natural habitats and by climate change, risking the maintenance of biodiversity, ecosystem functions, and human welfare. Research oriented towards a better understanding of the joint effects of land use and climate change over the provision of specific ecosystem services is therefore essential to safeguard such services. Here we propose a methodological framework, which integrates species distribution forecasts and graph theory to identify key conservation areas, which if protected or restored could improve habitat connectivity and safeguard ecosystem services. We applied the proposed framework to the provision of pollination services by a tropical stingless bee (Melipona quadrifasciata), a key pollinator of native flora from the Brazilian Atlantic Forest and important agricultural crops. Based on the current distribution of this bee and that of the plant species used to feed and nest, we projected the joint distribution of bees and plants in the future, considering a moderate climate change scenario (following IPPC). We then used this information, the bee's flight range, and the current mapping of Atlantic Forest remnants to infer habitat suitability and quantify local and regional habitat connectivity for 2030, 2050 and 2080. Our results revealed north to south and coastal to inland shifts in the pollinator distribution during the next 70 years. Current and future connectivity maps unraveled the most important corridors, which if protected or restored, could facilitate the dispersal and establishment of bees during distribution shifts. Our results also suggest that coffee plantations from eastern São Paulo and southern Minas Gerais States could suffer a pollinator deficit in the future, whereas pollination services seem to be secured in southern Brazil. Landowners and governmental agencies could use this information to implement new land use schemes. Overall, our proposed methodological framework could help design novel conservational and agricultural practices that can be crucial to conserve ecosystem services by buffering the joint effect of habitat configuration and climate change.


Assuntos
Mudança Climática , Ecossistema , Animais , Abelhas , Brasil , Florestas , Geografia , Humanos , Polinização
14.
Biotechnol Rep (Amst) ; 8: 152-159, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28352585

RESUMO

A gram-positive bacterium, denominated CFA-06, was isolated from Brazilian petroleum in the Campos Basin and is responsible for the degradation of aromatic compounds and petroleum aromatic fractions. The CFA-06 strain was identified as Bacillus safensis using the 16S rRNA and gyrase B sequence. Enzymatic assays revealed the presence of two oxidoreductases: a catalase and a new oxidoreductase. The oxidoreductases were enzymatically digested and analyzed via ESI-LTQ-Orbitrap mass spectrometry. The mass data revealed a novel oxidoreductase (named BsPMO) containing 224 amino acids and 89% homology with a hypothetic protein from B. safensis (CFA-06) and a catalase (named BsCat) with 491 amino acids and 60% similarity with the catalase from Bacillus pumilus (SAFR-032). The new protein BsPMO contains iron atom(s) and shows catalytic activity toward a monooxygenase fluorogenic probe in the presence of cofactors (NADH, NADPH and NAD). This study enhances our knowledge of the biodegradation process of petroleum by B. safensis.

15.
Microb Pathog ; 59-60: 1-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23474016

RESUMO

The 5'-nucleotidases constitute a ubiquitous family of enzymes that catalyze either the hydrolysis or the transfer of esterified phosphate at the 5' position of nucleoside monophosphates. These enzymes are responsible for the regulation of nucleotide and nucleoside levels in the cell and can interfere with the phosphorylation-dependent activation of nucleoside analogs used in therapies targeting solid tumors and viral infections. In the present study, we report the initial biochemical and functional characterization of a 5'-nucleotidase from Xylella fastidiosa that is related to the human cytosolic 5'-nucleotidase I. X. fastidiosa is a plant pathogenic bacterium that is responsible for numerous economically important crop diseases. Biochemical assays confirmed the phosphatase activity of the recombinant purified enzyme and revealed metal ion dependence for full enzyme activity. In addition, we investigated the involvement of Xf5'-Nt in the formation of X. fastidiosa biofilms, which are structures that occlude the xylem vessels of susceptible plants and are strictly associated with bacterial pathogenesis. Using polyclonal antibodies against Xf5'-Nt, we observed an overexpression of Xf5'-Nt during the initial phases of X. fastidiosa biofilm formation that was not observed during X. fastidiosa planktonic growth. Our results demonstrate that the de/phosphorylation network catalyzed by 5'-nucleotidases may play an important role in bacterial biofilm formation, thereby contributing novel insights into bacterial nucleotide metabolism and pathogenicity.


Assuntos
5'-Nucleotidase/metabolismo , Xylella/enzimologia , 5'-Nucleotidase/genética , 5'-Nucleotidase/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Coenzimas/metabolismo , Perfilação da Expressão Gênica , Metais/metabolismo , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/isolamento & purificação , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Xylella/fisiologia
16.
FEBS J ; 279(20): 3828-43, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22889056

RESUMO

Xylella fastidiosa is a Gram-negative bacterium that grows as a biofilm inside the xylem vessels of susceptible plants and causes several economically relevant crop diseases. In the present study, we report the functional and low-resolution structural characterization of the X. fastidiosa disulfide isomerase DsbC (XfDsbC). DsbC is part of the disulfide bond reduction/isomerization pathway in the bacterial periplasm and plays an important role in oxidative protein folding. In the present study, we demonstrate the presence of XfDsbC during different stages of X. fastidiosa biofilm development. XfDsbC was not detected during X. fastidiosa planktonic growth; however, after administering a sublethal copper shock, we observed an overexpression of XfDsbC that also occurred during planktonic growth. These results suggest that X. fastidiosa can use XfDsbC in vivo under oxidative stress conditions similar to those induced by copper. In addition, using dynamic light scattering and small-angle X-ray scattering, we observed that the oligomeric state of XfDsbC in vitro may be dependent on the redox environment. Under reducing conditions, XfDsbC is present as a dimer, whereas a putative tetrameric form was observed under nonreducing conditions. Taken together, our findings demonstrate the overexpression of XfDsbC during biofilm formation and provide the first structural model of a bacterial disulfide isomerase in solution.


Assuntos
Proteínas de Bactérias/química , Isomerases de Dissulfetos de Proteínas/química , Multimerização Proteica , Xylella/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Cobre/farmacologia , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Teste de Complementação Genética , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Oxirredução , Doenças das Plantas/microbiologia , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Estrutura Quaternária de Proteína , Espalhamento a Baixo Ângulo , Homologia de Sequência de Aminoácidos , Difração de Raios X , Xylella/genética , Xylella/fisiologia
17.
FEBS J ; 276(22): 6751-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19843181

RESUMO

The genome data of bacterium Xylella fastidiosa strain 9a5c has identified several orfs related to its phytopathogenic adaptation and survival. Among these genes, the surE codifies a survival protein E (XfSurE) whose function is not so well understood, but functional assays in Escherichia coli revealed nucleotidase and exopolyphosphate activity. In the present study, we report the XfSurE protein overexpression in E. coli and its purification. The overall secondary structure was analyzed by CD. Small-angle X-ray scattering and gel filtration techniques demonstrated that the oligomeric state of the protein in solution is a tetramer. In addition, functional kinetics experiments were carried out with several monophosphate nucleoside substrates and revealed a highly positive cooperativity. An allosteric mechanism involving torsion movements in solution is proposed to explain the cooperative behaviour of XfSurE. This is the first characterization of a SurE enzyme from a phytopathogen organism and, to our knowledge, the first solution structure of a SurE protein to be described.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Espalhamento a Baixo Ângulo , Raios X , Xylella/metabolismo , Regulação Alostérica , Cromatografia em Gel , Dicroísmo Circular , Multimerização Proteica , Estrutura Secundária de Proteína
18.
Rev. bras. farmacogn ; 16(4): 506-509, out.-dez. 2006. tab
Artigo em Inglês | LILACS | ID: lil-451528

RESUMO

Lippia alba (Mill.) N.E. Brown (Verbenaceae) is commonly used in the Brazilian folk medicine to the treatment of gastric illnesses, diarrhea, fever, asthma, and as a tranquilizer. This work evaluated the antimicrobial activity of ethyl acetate, methanol and aqueous extracts from the roots of the L. alba using plates-holes diffusion assay and the phytochemical profile. The results obtained showed that the ethyl acetate and methanol extracts presented antimicrobial activity against Staphylococcus aureus (ATCC 6538P), Staphylococcus aureus (ATCC 6538) and Klebsiella pneumonia (ATCC 10031). Terpenoids, phenylpropanoids and sugars were detected in the phytochemical analysis.


Lippia alba (Mill.) N.E. Brown (Verbenaceae) é geralmente usada na medicina popular brasileira para o tratamento de doenças gástricas, febre, asma e como tranqüilizante. Este trabalho avaliou a atividade antimicrobiana dos extratos acetato de etila, metanol e aquoso das raízes de L. alba usando métodos de difusão em poços e o perfil fitoquímico. Os resultados obtidos mostraram que os extratos acetato de etila e metanol apresentaram atividade antimicrobiana contra Staphylococcus aureus (ATCC 6538P), Staphylococcus aureus (ATCC 6538) e Klebsiella pneumonia (ATCC 10031). Terpenóides, fenilpropanóides e açúcares foram detectados na análise fitoquímica.

19.
Arch Biochem Biophys ; 453(2): 143-50, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16919232

RESUMO

The Xylella fastidiosa genome program generated a large number of gene sequences that belong to pathogenicity, virulence and adaptation categories from this important plant pathogen. One of these genes (XF1729) encodes a protein similar to a superfamily of aldo-keto reductase together with a number of structurally and functionally related NADPH-dependent oxidoreductases. In this work, the similar sequence XF1729 from X. fastidiosa was cloned onto the pET32Xa/LIC vector in order to overexpress a recombinant His-tag fusion protein in Escherichia coli BL21(DE3). The expressed protein in the soluble fraction was purified by immobilized metal affinity chromatography (agarose-IDA-Ni resin). Secondary structure contents were verified by circular dichroism spectroscopy. Small angle X-ray scattering (SAXS) measurements furnish general structural parameters and provide a strong indication that the protein has a monomeric form in solution. Also, ab initio calculations show that the protein has some similarities with a previously crystallized aldo-keto reductase protein. The recombinant XF1729 purified to homogeneity catalyzed the reduction of dl-glyceraldehyde (K(cat) 2.26s(-1), Km 8.20+/-0.98 mM) and 2-nitrobenzaldehyde (K(cat) 11.74 s(-1), Km 0.14+/-0.04 mM) in the presence of NADPH. The amino acid sequence deduced from XF1729 showed the highest identity (40% or higher) with several functional unknown proteins. Among the identified AKRs, we found approximately 29% of identity with YakC (AKR13), 30 and 28% with AKR11A and AKR11B, respectively. The results establish XF1729 as the new member of AKR family, AKR13B1. Finally, the first characterization by gel filtration chromatography assays indicates that the protein has an elongated shape, which generates an apparent higher molecular weight. The study of this protein is an effort to fight X. fastidiosa, which causes tremendous losses in many economically important plants.


Assuntos
Oxirredutases do Álcool/química , Oxirredutases do Álcool/isolamento & purificação , Modelos Químicos , Modelos Moleculares , Xylella/enzimologia , Oxirredutases do Álcool/metabolismo , Aldeído Redutase , Aldo-Ceto Redutases , Sequência de Aminoácidos , Simulação por Computador , Ativação Enzimática , Dados de Sequência Molecular , Peso Molecular , Conformação Proteica , Xylella/genética , Xylella/metabolismo
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