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1.
Braz. j. microbiol ; 49(4): 685-694, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974282

RESUMO

ABSTRACT To mitigate the deleterious effects of abiotic stress, the use of plant growth-promoting bacteria along with diazotrophic bacteria has been increasing. The objectives of this study were to investigate the key enzymes related to nitrogen and carbon metabolism in the biological nitrogen fixation process and to elucidate the activities of these enzymes by the synergistic interaction between Bradyrhizobium and plant growth-promoting bacteria in the absence and presence of salt stress. Cowpea plants were cultivated under axenic conditions, inoculated with Bradyrhizobium and co-inoculated with Bradyrhizobium sp. and Actinomadura sp., Bradyrhizobium sp. and Bacillus sp., Bradyrhizobium sp. and Paenibacillus graminis, and Bradyrhizobium sp. and Streptomycessp.; the plants were also maintained in the absence (control) and presence of salt stress (50 mmolL-1 NaCl). Salinity reduced the amino acids, free ammonia, ureides, proteins and total nitrogen content in nodules and increased the levels of sucrose and soluble sugars. The co-inoculations responded differently to the activity of glutamine synthetase enzymes under salt stress, as well as glutamate synthase, glutamate dehydrogenase aminating, and acid invertase in the control and salt stress. Considering the development conditions of this experiment, co-inoculation with Bradyrhizobium sp. and Bacillus sp. in cowpea provided better symbiotic performance, mitigating the deleterious effects of salt stress.


Assuntos
Carbono/metabolismo , Cloreto de Sódio/metabolismo , Vigna/metabolismo , Nitrogênio/metabolismo , Microbiologia do Solo , Cloreto de Sódio/análise , Actinobacteria/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Bradyrhizobium/fisiologia , Inoculantes Agrícolas/fisiologia , Vigna/crescimento & desenvolvimento , Vigna/microbiologia , Aminoácidos/metabolismo , Fixação de Nitrogênio
2.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 55(3): e141243, Outubro 25, 2018. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-969229

RESUMO

Actinobacteria have been researched as a source that produces crude extracts, which contain bioactive compounds able to act as antimicrobial agents. The present investigation evaluated the dose-response effect of two crude extracts, obtained at Caatinga rhizosphere (Caat) and Rhizophora mangle (AMC), on in vitro ruminal fermentation by:cumulative gas production, digestibility of dry (IVDMD) and organic matter (IVOMD), and short-chain fatty acids concentration (SCFA). Three multiparous Holstein dairy cows with ruminal fistula were used as the inoculum donors and fed a basal diet consisting of corn silage, soybean meal, urea, ground corn and mineral supplement. Ruminal fluid samples were incubated in glass bottles with 1 g of the dried and milled diet, a buffer solution, and the crude extracts evaluated in four doses (0.3, 0.6, 0.9 and 1.20 mg/10 mL inoculum) in a randomized block design, and the donators were considered as blocks with random effects. Additionally, negative controls were used. The results were expressed as average values based on triplicate analyses. Decreased cumulative gas production was observed according to linear dose response at 24, 48 and 72 h of incubation with the addition of Caat extract. The IVOMD showed a linear decrease at 72 h of incubation with dose Caat inclusion. Furthermore, the inclusion of Caat extract linearly reduced butyric and isovaleric acid concentrations, as well as acetate:propionate ratio. Finally, the Caat inclusion increased the propionic acid concentration in comparison to AMC extract. However, the inclusion of AMC extract did not affect any of the analyzed variables at the used doses. The Caat extract could be used as a modulator of in vitro ruminal fermentation, since it reduced acetate:propionate ratio and cumulative gas production.(AU)


As actinobactérias têm sido pesquisadas como fonte produtoras de extratos brutos que contêm compostos bioativos capazes de atuar como agentes antimicrobianos. O presente trabalho investigou o efeito dose-resposta de dois extratos brutos, AMC e Caat, na fermentação ruminal in vitro por: produção cumulativa de gás, digestibilidade in vitro da matéria seca (IVDMD) e matéria orgânica (IVOMD) e concentração de ácidos graxos de cadeia curta (SCFA). Três vacas leiteiras da raça Holandesa, multíparas e portadoras de fístula ruminal foram utilizadas como doadoras de inóculo ruminal e foram alimentadas com uma dieta basal composta por silagem de milho, farelo de soja, ureia, milho moído e suplemento mineral. As amostras de inóculo ruminal foram incubadas em garrafas de vidro com 1 g da dieta seca e moída, solução tampão e os extratos brutos avaliados em quatro doses (0,3, 0,6, 0,9 e 1,20 mg/10 mL de inóculo) em delineamento em blocos casualizados, sendo as doadoras consideradas os blocos como efeito aleatório. Além disso, foram utilizados controles negativos para a correção da produção de gás. Os resultados foram expressos como valores médios com base em análises triplicadas. A diminuição da produção cumulativa de gás foi observada de acordo com a dose em resposta linear às 24, 48 e 72 h de incubação com a adição de extrato de Caat. A IVOMD mostrou uma diminuição linear com 72 h de incubação com inclusão de Caat. Além disso, a inclusão do Caat reduziu linearmente as concentrações de ácido butírico e isovalérico, bem como a proporção de acetato/propionato. Diferentemente, a inclusão do extrato de AMC não afetou nenhuma das variáveis analisadas nas doses utilizadas. O extrato de Caat pode ser usado como um modulador da fermentação ruminal in vitro, uma vez que reduziu a proporção de acetato/propionato e a produção de gás acumulada. (AU)


Assuntos
Actinobacteria/química , Fermentação , Ionóforos/síntese química
3.
Braz. j. microbiol ; 49(2): 258-268, Apr.-June 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889233

RESUMO

Abstract Cellulosimicrobium cellulans CWS2, a novel strain capable of utilizing benzo(a)pyrene (BaP) as the sole carbon and energy source under nitrate-reducing conditions, was isolated from PAH-contaminated soil. Temperature and pH significantly affected BaP biodegradation, and the strain exhibited enhanced biodegradation ability at temperatures above 30 °C and between pH 7 and 10. The highest BaP removal rate (78.8%) was observed in 13 days when the initial BaP concentration was 10 mg/L, and the strain degraded BaP at constant rate even at a higher concentration (50 mg/L). Metal exposure experimental results illustrated that Cd(II) was the only metal ion that significantly inhibited biodegradation of BaP. The addition of 0.5 and 1.0 g/L glucose enhanced BaP biodegradation, while the addition of low-molecular-weight organic acids with stronger acidity reduced BaP removal rates during co-metabolic biodegradation. The addition of phenanthrene and pyrene, which were degraded to some extent by the strain, showed no distinct effect on BaP biodegradation. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the five rings of BaP opened, producing compounds with one to four rings which were more bioavailable. Thus, the strain exhibited strong BaP degradation capability and has great potential in the remediation of BaP-/PAH-contaminated environments.


Assuntos
Microbiologia do Solo , Poluentes do Solo/metabolismo , Benzo(a)pireno/metabolismo , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Temperatura , Cádmio/metabolismo , Carbono/metabolismo , Ácidos Carboxílicos/metabolismo , Biotransformação , Actinobacteria/classificação , Meios de Cultura/química , Inibidores Enzimáticos/metabolismo , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Anaerobiose , Cromatografia Gasosa-Espectrometria de Massas
4.
Braz. j. microbiol ; 49(1): 79-86, Jan.-Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889208

RESUMO

ABSTRACT Repeated application of pesticides disturbs microbial communities and cause dysfunctions on soil biological processes. Granstar® 75 DF is one of the most used sulfonylurea herbicides on cereal crops; it contains 75% of tribenuron-methyl. Assessing the changes on soil microbiota, particularly on the most abundant bacterial groups, will be a useful approach to determine the impact of Granstar® herbicide. For this purpose, we analyzed Actinobacteria, which are known for their diversity, abundance, and aptitude to resist to xenobiotic substances. Using a selective medium for Actinobacteria, 42 strains were isolated from both untreated and Granstar® treated soils. The number of isolates recovered from the treated agricultural soil was fewer than that isolated from the corresponding untreated soil, suggesting a negative effect of Granstar® herbicide on Actinobacteria community. Even so, the number of strains isolated from untreated and treated forest soil was quite similar. Among the isolates, resistant strains, tolerating high doses of Granstar® ranging from 0.3 to 0.6% (v/v), were obtained. The two most resistant strains (SRK12 and SRK17) were isolated from treated soils showing the importance of prior exposure to herbicides for bacterial adaptation. SRK12 and SRK17 strains showed different morphological features. The phylogenetic analysis, based on 16S rRNA gene sequencing, clustered the SRK12 strain with four Streptomyces type strains (S. vinaceusdrappus, S. mutabilis, S. ghanaensis and S. enissocaesilis), while SRK17 strain was closely related to Streptomyces africanus. Both strains were unable to grow on tribenuron methyl as unique source of carbon, despite its advanced dissipation. On the other hand, when glucose was added to tribenuron methyl, the bacterial development was evident with even an improvement of the tribenuron methyl degradation. In all cases, as tribenuron methyl disappeared, two compounds were detected with increased concentrations. These by-products appeared to be persistent and were not degraded either chemically or by the studied strains. Based on these observations, we suggested that bacterial activity on carbon substrates could be directly involved in the partial breakdown of tribenuron methyl, by generating the required acidity for the first step of the hydrolysis. Such a process would be interesting to consider in bioremediation of neutral and alkaline tribenuron methyl-polluted soils.


Assuntos
Actinobacteria/efeitos dos fármacos , Actinobacteria/crescimento & desenvolvimento , Sulfonatos de Arila/farmacologia , Actinobacteria/genética , Actinobacteria/metabolismo , Sulfonatos de Arila/metabolismo
5.
Braz. j. microbiol ; 48(4): 637-647, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889185

RESUMO

ABSTRACT Role of microbes in bioremediation of oil spills has become inevitable owing to their eco friendly nature. This study focused on the isolation and characterization of bacterial strains with superior oil degrading potential from crude-oil contaminated soil. Three such bacterial strains were selected and subsequently identified by 16S rRNA gene sequence analysis as Corynebacterium aurimucosum, Acinetobacter baumannii and Microbacterium hydrocarbonoxydans respectively. The specific activity of catechol 1,2 dioxygenase (C12O) and catechol 2,3 dioxygenase (C23O) was determined in these three strains wherein the activity of C12O was more than that of C23O. Among the three strains, Microbacterium hydrocarbonoxydans exhibited superior crude oil degrading ability as evidenced by its superior growth rate in crude oil enriched medium and enhanced activity of dioxygenases. Also degradation of total petroleum hydrocarbon (TPH) in crude oil was higher with Microbacterium hydrocarbonoxydans. The three strains also produced biosurfactants of glycolipid nature as indicated d by biochemical, FTIR and GCMS analysis. These findings emphasize that such bacterial strains with superior oil degrading capacity may find their potential application in bioremediation of oil spills and conservation of marine and soil ecosystem.


Assuntos
Poluentes do Solo/metabolismo , Tensoativos/metabolismo , Proteínas de Bactérias/metabolismo , Petróleo/microbiologia , Actinobacteria/metabolismo , Corynebacterium/metabolismo , Acinetobacter baumannii/metabolismo , Dioxigenases/metabolismo , Filogenia , Microbiologia do Solo , Tensoativos/química , Proteínas de Bactérias/genética , Biodegradação Ambiental , Petróleo/análise , Poluição por Petróleo/análise , Actinobacteria/crescimento & desenvolvimento , Actinobacteria/enzimologia , Actinobacteria/genética , Corynebacterium/crescimento & desenvolvimento , Corynebacterium/enzimologia , Corynebacterium/genética , Acinetobacter baumannii/crescimento & desenvolvimento , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Dioxigenases/genética , Índia
6.
Rev. méd. hered ; 28(4): 236-241, oct.-dic. 2017. graf
Artigo em Espanhol | LILACS, LIPECS | ID: biblio-991434

RESUMO

Objetivos: Determinar la frecuencia de microorganismos y el patrón de susceptibilidad antimicrobiana en aislamientos de cultivos de secreción endotraqueal en la unidad de cuidados intensivos de un hospital nacional de Lima. Material y métodos: Estudio observacional, descriptivo. Se incluyeron 195 cultivos positivos de secreción endotraqueal de pacientes en ventilación mecánica durante el periodo enero a diciembre del 2016. Resultados: Acinetobacter sp. fue la bacteria más frecuentemente aislada (28%) seguido por Pseudomonas aeruginosa (22%) y Klebsiella pneumoniae (14%), Los aislamientos con Acinetobacter sp. presentaron una elevada resistencia a antibióticos carbapenémicos (meropenem 90% eimipenem 88%). Conclusiones: Se identificó una elevada frecuencia de Acinetobacter sp. En cultivos de secreción traqueal en la unidad de cuidados intensivos, con un patrón de multirresistencia. (AU)


Objectives: To determine the prevalence of micro-organisms and their susceptibility pattern among endotracheal isolates in an intensive care unit in national hospital in Lima. Methods: An observational, descriptive study was carried-out from January to December 2016, 195 positive isolates from endotracheal aspirates of patients under mechanical ventilation were analyzed. Results: Acinetobacter spp. was the most common bacteria isolates (28%), followed by Pseudomonas aeruginosa (22%) and Klebsiella pneumoniae (14%). Acinetobacter spp. was highly resistant to carbapenems (90% to meropenem and 88% to imipenem). Conclusions: Multi-drug resistant Acinetobacter spp. was the most common pathogen isolated in this setting. (AU)


Assuntos
Humanos , Traqueia , Actinobacteria , Secreções Corporais , Unidades de Terapia Intensiva , Epidemiologia Descritiva , Estudos Observacionais como Assunto
7.
Braz. dent. j ; 28(3): 372-379, May-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888654

RESUMO

Abstract Psidium cattleianum (PC) has been displaying inhibitory effect against a variety of microorganisms, but this effect has not yet been tested against endodontic pathogens. The aim of this study was to evaluate the antimicrobial activity and biocompatibility of the aqueous (PCAE) and hydroethanolic (PCHE) extracts from Psidium cattleianum (PC) leaves. Minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were determined using the microdilution broth method in order to analyze the antimicrobial effect against Enterococcus faecalis, Pseudomonas aeruginosa, Actinomyces israelii and Candida albicans in planktonic conditions. Biofilm assays were conducted only with the extracts that were able to determine the MLC for microorganisms in planktonic conditions. Immediate and late tissue reactions against PC extracts were evaluated using edemogenic test and histological analysis of subcutaneous implants in Wistar rats. The results showed that the MIC and MLC values ranged between 0.25 and 4 mg/mL. The MLC obtained for PCHE inhibited 100% growth of all the tested strains, except for C. albicans. PCAE had the same effect for E. faecalis and P. aeruginosa. Both PC extracts were able to eliminate E. faecalis biofilms and only the PCHE eliminated P. aeruginosa biofilms. The positive controls inhibited the growth of all tested strains in MIC and MLC essays, but no CHX tested concentrations were able to eliminate A. israelii biofilm. PCAE caused a discrete increase in the edema over time, while PCHE caused a higher initial edema, which decreased progressively. Both PCAE and PCHE extracts were biocompatible, but PCHE showed better results with slight levels of inflammation at 28 days. In conclusion, PCHE was biocompatible and presented better antimicrobial effect against important pathogens associated with persistent endodontic infections


Resumo Psidium cattleianum (PC) tem apresentado atividade inibitória frente diversos microrganismos, entretanto esse efeito ainda não foi testado contra microrganismos de interesse endodôntico. O objetivo desse estudo foi avaliar a atividade antimicrobiana e a biocompatibilidade dos extratos aquoso (EAPC) e hidroetanólico (EHPC) das folhas de Psidium cattleianum. As concentrações inibitória mínima (CIM) e letal mínima (CLM) foram determinadas pelo método de microdiluição em caldo, com o objetivo de analisar o efeito antimicrobiano frente Enterococcus faecalis, Pseudomonas aeruginosa, Actinomyces israelii e Candida albicans em condições planctônicas. Os ensaios de biofilme foram realizados somente com os extratos em que se determinou a CLM frente os microrganismos em condições planctônicas. Respostas teciduais imediata e tardia frente aos extratos de Psidium cattleianum foram avaliadas por teste edemogênico e análise histológica de implantes subcutâneos em ratos Wistar. Os resultados mostraram que CIM e CLM variaram entre 0,25 e 4 mg/mL. As CLMs determinadas pelo EHPC inibiram 100% do crescimento de todas as cepas testadas, exceto Candida albicans. EAPC apresentou o mesmo efeito para E. faecalis e P. aeruginosa. Ambos os extratos de PC conseguiram eliminar o biofilme de E. faecalis, e somente o EHPC eliminou o biofilme de P. aeruginosa. Os controles positivos inibiram o crescimento de todos os microrganismos testados nos ensaios de CIM e CLM, mas nenhuma das concentrações de clorexidina testadas foi capaz de eliminar o biofilme de A. israelii. O EAPC provocou um discreto aumento de edema com o tempo, enquanto EHPC provocou um edema inicial severo, que diminuiu progressivamente. Ambos os extratos EAPC e EHPC foram biocompatíveis, entretanto, EHPC apresentou melhores resultados com baixos níveis de inflamação em 28 dias. Pode-se concluir que EHPC foi biocompatível e apresentou melhor efeito antimicrobiano frente importantes patógenos associados a infecções endodônticas persistentes.


Assuntos
Animais , Masculino , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis , Extratos Vegetais/farmacologia , Psidium/química , Tratamento do Canal Radicular , Actinobacteria/efeitos dos fármacos , Biofilmes , Candida albicans/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos Wistar
8.
Braz. j. microbiol ; 48(1): 32-36, Jan.-Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839352

RESUMO

Abstract Actinobacteria occur in many environments and have the capacity to produce secondary metabolites with antibiotic potential. Identification and taxonomy of actinobacteria that produce antimicrobial substances is essential for the screening of new compounds, and sequencing of the 16S region of ribosomal DNA (rDNA), which is conserved and present in all bacteria, is an important method of identification. Melanized fungi are free-living organisms, which can also be pathogens of clinical importance. This work aimed to evaluate growth inhibition of melanized fungi by actinobacteria and to identify the latter to the species level. In this study, antimicrobial activity of 13 actinobacterial isolates from the genus Streptomyces was evaluated against seven melanized fungi of the genera Exophiala, Cladosporium, and Rhinocladiella. In all tests, all actinobacterial isolates showed inhibitory activity against all isolates of melanized fungi, and only one actinobacterial isolate had less efficient inhibitory activity. The 16S rDNA region of five previously unidentified actinobacterial isolates from Ilha do Mel, Paraná, Brazil, was sequenced; four of the isolates were identified as Streptomyces globisporus subsp. globisporus, and one isolate was identified as Streptomyces aureus. This work highlights the potential of actinobacteria with antifungal activity and their role in the pursuit of novel antimicrobial substances.


Assuntos
Actinobacteria/fisiologia , Fungos/fisiologia , Antibiose , Filogenia , Streptomyces/classificação , Streptomyces/genética , Brasil , RNA Ribossômico 16S/genética , Actinobacteria/isolamento & purificação , Actinobacteria/classificação , Actinobacteria/genética
9.
Electron. j. biotechnol ; 25: 21-27, ene. 2017. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1008381

RESUMO

Background: Biomineralization is a significant process performed by living organisms in which minerals are produced through the hardening of biological tissues. Herein, we focus on calcium carbonate precipitation, as part of biomineralization, to be used in applications for environmental protection, material technology, and other fields. A strain GM-1, Microbacterium sp. GM-1, isolated from active sludge, was investigated for its ability to produce urease and induce calcium carbonate precipitation in a metabolic process. Results: It was discovered that Microbacterium sp. GM-1 resisted high concentrations of urea up to 60 g/L. In order to optimize the calcification process of Microbacterium sp. GM-1, the concentrations of Ni2+ and urea, pH value, and culture time were analyzed through orthogonal tests. The favored calcite precipitation culture conditions were as follows: the concentration of Ni2+ and urea were 50 µM and 60 g/L, respectively, pH of 10, and culture time of 96 h. Using X-ray diffraction analysis, the calcium carbonate polymorphs produced by Microbacterium sp. GM-1 were proven to be mainly calcite. Conclusions: The results of this research provide evidence that Microbacterium sp. GM-1 can biologically induce calcification and suggest that strain GM-1 may play a potential role in the synthesis of new biominerals and in bioremediation or biorecovery.


Assuntos
Actinobacteria/metabolismo , Precipitação Química , Ureia/metabolismo , Calcificação Fisiológica , Carbonato de Cálcio/metabolismo , Actinobacteria/isolamento & purificação , Actinobacteria/química , Hidrólise , Níquel/metabolismo
10.
Biosci. j. (Online) ; 32(5): 1314-1323, sept./oct 2016. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-965726

RESUMO

The most practical approach to reduce morbidity and mortality of coronary heart disease (CHD) is to delay the process of thrombus by usage of clot-dissolving agents. The necessities of such safer compounds are to be critically examined for thrombolytic activity especially, from marine sources. Thrombolytic agents have been investigated as a possible treatment for thrombus. The aim of this study was to investigate the in vitro thrombolytic potential of Streptomyces sp.VITJS4 (NCIM No. 5574); (ACC No: JQ234978.1) active compounds. The fibrin degradation revealed a clear transparent zone of clearance with 500µg/mL concentration showing 24mm hydrolysis. The thrombolytic effect of Streptomyces sp.VITJS4 compounds was also demonstrated in vitro clot lysis assay where The percent of thrombolysis by the crude extract showed 90±1.7% at the concentration of 1000µg/mL, whereas percent of thrombolysis by streptokinase was found 100± 00%%. The bioactive compounds were further studied for spectrophotometric analysis. The UV-VIS profile showed different peaks ranging from 400-700 nm with different absorption respectively. The data confirmed the presence of both analogues with absorption maxima at 210 and 310 nm. A sensitive method using LC-MS technique was optimized for the separation and identification of bioactive metabolites which was indicated by the fingerprints. The results of the LC-MS analysis provided different peaks determining the presence of compounds with different therapeutic activities. The current study refers the bioactive compound as impressive thrombolytic agent for further laboratory study. Further studies should be conducted to ensure the efficacy and safety of different concentration of bioactive compounds for drug development. Hence the results reported perhaps useful for the discovery of novel thrombolytic drugs from marine origin.


A abordagem mais prática para reduzir a morbidade e a mortalidade da doença arterial coronariana (CHD, do inglês coronary heart disease) consiste em retardar o processo de trombo através da utilização de agentes de dissolução de coágulos. As necessidades de tais compostos mais seguros devem ser criticamente examinadas para a atividade trombolítica, especialmente de fontes marinhas. Agentes trombolíticos tem sido estudados como um possível tratamento para o trombo. O objetivo deste estudo foi investigar o potencial trombolítico in vitro dos compostos ativos do Streptomyces sp.VITJS4 (NCIM No. 5574); (ACC No: JQ234978.1). A degradação da fibrina revelou um clara zona livre transparente com concentração de 500µg/mL mostrando uma hidrólise de 24mm. O efeito trombolítico dos compostos de Streptomyces sp.VITJS4 também foi demonstrado no ensaio in vitro de lise dos coágulos em que a percentagem de trombólise pelo extrato bruto mostrou 90±1.7% a uma concentração de 1000µg/mL, enquanto que a percentagem de trombólise pela estreptoquinase foi de 100± 00%. Os compostos bioativos foram estudados posteriormente através da análise espectrofotométrica. O perfil ultra violeta visível (UV-VIS profile, em inglês) mostrou diferentes picos variando entre 400-700 nm com diferentes absorções respectivamente. Os dados confirmaram a presença de ambos os análogos com absorção máxima em 210 e 300 nm. Um método sensível usando a técnica LC-MS (Liquid chromatography­mass spectrometry) foi otimizado para a separação e identificação metabólitos bioativos que foram indicados pelas impressões digitais (?). Os resultados da análise LC-MS forneceram diferentes picos determinando a presença de compostos com diferentes atividades terapêuticas. O estudo atual refere-se ao composto bioativo como um agente trombolítico impressionante para futuros estudos em laboratório. Estudos futuros devem ser conduzidos para assegurar a eficácia e segurança de diferentes concentrações dos compostos bioativos para o desenvolvimento de drogas. Assim, os resultados reportados talvez sejam úteis para a descoberta de novas drogas trombolíticas de origem marinha.


Assuntos
Streptomyces , Trombose , Técnicas In Vitro , Actinobacteria , Fibrinolíticos
11.
Pesqui. vet. bras ; 36(7): 587-590, jul. 2016. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: lil-794767

RESUMO

The caudal vena cava thrombosis, or pulmonary thromboembolism, in cattle is correlated with lactic acidosis, caused by diets rich in grains and highly fermentable, associated or not to septic situations, used in feedlots of beef or high-producing dairy cattle. This paper reports an unusual caudal vena cava thrombosis in a cow, secondary to Trueperella (Arcanobacterium) pyogenes infection, resulting in reduced milk production, anorexia, pale mucous membranes, ruminal atony, sternal decubitus and autoauscultation position. The heart was enlarged at necropsy, presence of clots distributed along the thoracic cavity, adherence between lung and pleura, abscesses, emphysema, petechiae, suffusions and ecchymosis in lungs, thickening of the caudal vena cava wall, hepatomegaly with chronic passive congestion ("nutmeg" aspect), and rumenitis. In lab, the actinomycete Trueperella (Arcanobacterium) pyogenes was isolated from liver and lung samples, probably resulting through dissemination of the bacteria of the rumen content, what reaffirms the opportunistic behavior of this actinomycete.(AU)


A síndrome da veia cava caudal ou tromboembolismo pulmonar bovino está relacionada à acidose láctica causada por dietas ricas em grãos e altamente fermentáveis, associados ou não a quadros sépticos, usadas em confinamentos de bovinos de corte ou para vacas leiteiras de alta produção. O presente artigo reporta caso raro de trombose da veia cava caudal em uma vaca, secundária a infecção por Trueperella (Arcanobacterium) pyogenes, apresentando reduzida produção de leite, anorexia, palidez de mucosas, atonia ruminal, decúbito esternal e posição de autoauscultação. À necrópsia observou-se coração aumentado de tamanho, coágulos distribuídos por toda cavidade torácica, aderência entre os pulmões e pleura, abscessos, enfisema, petéquias, sufusões, equimoses nos pulmões, espessamento da parede da veia cava caudal com trombo, hepatomegalia com congestão passiva crônica (aspecto de "noz moscada"), e ruminite. Em laboratório isolou-se o actinomiceto Trueperella (Arcanobacterium) pyogenes a partir de amostras de fígado e pulmão, provavelmente resultando da disseminação da bactéria proveniente do conteúdo ruminal, e reafirma o comportamento oportunista deste actinomiceto.(AU)


Assuntos
Animais , Feminino , Bovinos , Actinobacteria/isolamento & purificação , Arcanobacterium/patogenicidade , Embolia Pulmonar/veterinária , Veias Cavas/patologia , Abscesso/veterinária , Acidose Láctica/veterinária
12.
Braz. j. microbiol ; 47(1): 85-95, Jan.-Mar. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-775117

RESUMO

Abstract The main objective of the present study was to isolate and characterize actinomycetes for their plant growth-promotion in chickpea. A total of 89 actinomycetes were screened for their antagonism against fungal pathogens of chickpea by dual culture and metabolite production assays. Four most promising actinomycetes were evaluated for their physiological and plant growth-promotion properties under in vitro and in vivo conditions. All the isolates exhibited good growth at temperatures from 20 °C to 40 °C, pH range of 7–11 and NaCl concentrations up to 8%. These were also found highly tolerant to Bavistin, slightly tolerant to Thiram and Captan (except VAI-7 and VAI-40) but susceptible to Benlate and Ridomil at field application levels and were found to produce siderophore, cellulase, lipase, protease, chitinase (except VAI-40), hydrocyanic acid (except VAI-7 and VAI-40), indole acetic acid and β-1,3-glucanase. When the four actinomycetes were evaluated for their plant growth-promotion properties under field conditions on chickpea, all exhibited increase in nodule number, shoot weight and yield. The actinomycetes treated plots enhanced total N, available P and organic C over the un-inoculated control. The scanning electron microscope studies exhibited extensive colonization by actinomycetes on the root surface of chickpea. The expression profiles for indole acetic acid, siderophore and β-1,3-glucanase genes exhibited up-regulation for all three traits and in all four isolates. The actinomycetes were identified as Streptomyces but different species in the 16S rDNA analysis. It was concluded that the selected actinomycetes have good plant growth-promotion and biocontrol potentials on chickpea.


Assuntos
Actinobacteria/crescimento & desenvolvimento , Cicer/crescimento & desenvolvimento , Microbiologia do Solo , Actinobacteria/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Filogenia , Reguladores de Crescimento de Planta/metabolismo , Rizosfera , /genética , Análise de Sequência de DNA , Solo , Cloreto de Sódio/metabolismo , Temperatura
13.
Braz. j. microbiol ; 46(4): 1037-1044, Oct.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769646

RESUMO

In a previous study, three bacterial strains isolated from tropical hydrocarbon-contaminated soils and phylogenetically identified as Achromobacter sp. strain SL1, Pseudomonas sp. strain SL4 and Microbacterium esteraromaticum strain SL6 displayed angular dioxygenation and mineralization of carbazole in batch cultures. In this study, the ability of these isolates to survive and enhance carbazole degradation in soil were tested in field-moist microcosms. Strain SL4 had the highest survival rate (1.8 x 107 cfu/g) after 30 days of incubation in sterilized soil, while there was a decrease in population density in native (unsterilized) soil when compared with the initial population. Gas chromatographic analysis after 30 days of incubation showed that in sterilized soil amended with carbazole (100 mg/kg), 66.96, 82.15 and 68.54% were degraded by strains SL1, SL4 and SL6, respectively, with rates of degradation of 0.093, 0.114 and 0.095 mg kg−1 h−1. The combination of the three isolates as inoculum in sterilized soil degraded 87.13% carbazole at a rate of 0.121 mg kg−1 h−1. In native soil amended with carbazole (100 mg/kg), 91.64, 87.29 and 89.13% were degraded by strains SL1, SL4 and SL6 after 30 days of incubation, with rates of degradation of 0.127, 0.121 and 0.124 mg kg−1 h−1, respectively. This study successfully established the survivability (> 106 cfu/g detected after 30 days) and carbazole-degrading ability of these bacterial strains in soil, and highlights the potential of these isolates as seed for the bioremediation of carbazole-impacted environments.


Assuntos
Achromobacter/química , Achromobacter/genética , Achromobacter/isolamento & purificação , Achromobacter/metabolismo , Actinobacteria/química , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Biodegradação Ambiental/química , Biodegradação Ambiental/genética , Biodegradação Ambiental/isolamento & purificação , Biodegradação Ambiental/metabolismo , Carbazóis/química , Carbazóis/genética , Carbazóis/isolamento & purificação , Carbazóis/metabolismo , Filogenia/química , Filogenia/genética , Filogenia/isolamento & purificação , Filogenia/metabolismo , Pseudomonas/química , Pseudomonas/genética , Pseudomonas/isolamento & purificação , Pseudomonas/metabolismo , Microbiologia do Solo/química , Microbiologia do Solo/genética , Microbiologia do Solo/isolamento & purificação , Microbiologia do Solo/metabolismo , Poluentes do Solo/química , Poluentes do Solo/genética , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/metabolismo
14.
Braz. j. microbiol ; 45(2): 447-456, Apr.-June 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-723116

RESUMO

The interest in production of natural colorants by microbial fermentation has been currently increased. The effects of D-glucose concentration (3.18-36.82 g/L), inoculum size (12.5 x 10(9)-49.5 x 10(9) cfu cells/mL) and air-flow rate (1.95-12.05 L/L min) on the biomass, total carotenoid and canthaxanthin (CTX) accumulation of Dietzia natronolimnaea HS-1 in a batch bioreactor was scrutinized using a response surface methodology-central composite rotatable design (RSM-CCRD). Second-order polynomial models with high R² values ranging from 0.978 to 0.990 were developed for the studied responses using multiple linear regression analysis. The models showed the maximum cumulative amounts of biomass (7.85 g/L), total carotenoid (5.48 mg/L) and CTX (4.99 mg/L) could be achieved at 23.38 g/L of D-glucose, 31.2 x 10(9) cfu cells/mL of inoculation intensity and air-flow rate of 7.85 L/L min. The predicted values for optimum conditions were in good agreement with experimental data.


Assuntos
Actinobacteria/crescimento & desenvolvimento , Actinobacteria/metabolismo , Cantaxantina/biossíntese , Aerobiose , Ar , Carga Bacteriana , Técnicas de Cultura Celular por Lotes , Biomassa , Reatores Biológicos/microbiologia , Glucose/metabolismo , Modelos Estatísticos
15.
Rev. estomat. salud ; 21(2): 37-45, 20130000.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-877875

RESUMO

Introducción: Los sistemas de secreción bacterianos tipo IV tienen una variedad de funciones biológicas como el intercambio de material genético con otras bacterias y la translocación de ADN virulento, con sus proteínas efectoras, dentro de las células del huésped. Acinetobacter baumannii es un patógeno que causa infecciones en humanos y registra porcentajes altos de multiresistencia a fármacos. Objetivo: Relacionar el conocimiento so- bre los sistemas de secreción tipo IV con los patrones de resistencia y virulencia de Acinetobacter baumannii. Materiales y Métodos: Se realizó una buscada en PMC (NCBI) utilizando un conjunto de palabras claves. Resultados: De 133 artículos se analiza - ron 14 para establecer la relación entre los sistemas de secreción microbiano y la resistencia y virulencia de A. baumannii . Conclusiones: Los sistemas de secreción bacterianos tipo IV presentes en A. bau - mannii son una pieza clave en el enten - dimiento de los patrones de virulencia y resistencia...(Au)


Introduction: Type IV Bacterial Secretion Systems (TFSS) have a variety of biolo- gical functions such as the exchange of genetic material with other bacteria and virulent translocation of DNA with its effector proteins into host cells. A. bauman - nii is a pathogen that causes infections in humans and exhibits high rates of multidrug resistance to drugs. Objective: To relate how type IV secretion systems is associated with patterns of resistance and virulence in A. baumannii. Materials and Methods: Exhaustive search in PMC (NCBI) using a set of keywords was performed. Results: The search yielded 133 articles. Fourteen articles were analysed to deter - mine the bacterial secretion system and the resistant and virulence of AA. baumannii. Conclusions: Systems of bacterial type IV secretion present in A. baumannii are crucial in understanding the patterns of virulence and resistance...(Au)


Assuntos
Humanos , Actinobacteria , Odontologia , Diagnóstico Bucal , Transferência Genética Horizontal , Microbiologia , Medicina Bucal , Patologia Bucal , Revisão , Virulência , Fatores de Virulência , Acinetobacter baumannii , Farmacorresistência Bacteriana , Sistemas de Secreção Tipo IV
17.
Braz. j. microbiol ; 44(1): 325-328, 2013.
Artigo em Inglês | LILACS | ID: lil-676913

RESUMO

Bacteria associated with the parthenogenetic troglobiont sand fly Deanemyia maruaga were characterized by sequencing cloned 16S rDNA PCR products. Eleven novel partial 16S rDNA sequences, with varying degrees of similarity to Actinobacteria, were identified. None of the sequences identified had homology to those known from parthenogenesis-inducing bacteria.


Assuntos
Actinobacteria/genética , Actinobacteria/isolamento & purificação , Sequência de Bases , Clonagem Molecular , Dípteros/genética , Técnicas In Vitro , Microbiologia Industrial , Reação em Cadeia da Polimerase , Quirópteros , Métodos , Virulência
18.
Rev. colomb. biotecnol ; 14(2): 70-80, dic. 2012. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-671882

RESUMO

Las características fisicoquímicas de la lignina y su compactación con la celulosa han dificultado la explotación biotecnológica de enormes cantidades de biomasa vegetal. Las lacasas constituyen una subfamilia de oxidasas multicobre que intervienen en la despolimerización de la lignina. Si bien han sido ampliamente caracterizadas en los hongos, los estudios de la diversidad y las funcionalidades de las lacasas en los procariotas se han centrado especialmente en isoformas enzimáticas de Streptomyces sp. En este trabajo se aislaron 20 cepas de actinobacterias del suelo. La actividad lacasa de 17 de ellas fue evidenciada en ensayos cualitativos con guayacol y dos cepas seleccionadas fueron caracterizadas en detalle. Las pruebas morfológicas y el análisis de las secuencias del gen 16S rRNA apuntan a que estos dos aislados pertenecen a los géneros Tsukamurella y Cellulosimicrobium. En cultivo sumergido con agitación, AC01 (Tsukamurella sp.) expresó una máxima actividad de oxidación de ABTS (2,2’-azino-bis-(3-etilbenzotiazolin-6-sulfonato) de 108 U/L. Por otra parte, AC18 (Cellulosimicrobium sp.) que había exhibido una actividad oxidativa de guayacol superior a las 16 cepas restantes y demostró ser resistente a niveles tóxicos de cobre, logró un valor máximo de oxidación del ABTS de 0,56 U/L. Estos resultados sugieren que en el aislado AC18 operaría un fenómeno de especificidad de sustrato o de inductor, regulador de la expresión y de la actividad lacasa cuantificable. La caracterización genómica y funcional de las lacasas de nuevas actinobacterias lignocelulósicas ampliará la gama de centros redox con aplicaciones biotecnológicas específicas, además de facilitar el establecimiento de sus relaciones evolutivas con las eucariotas.


The physicochemical characteristics of lignin and its compaction with cellulose have restricted the biotechnological exploitation of enormous amounts of plant biomass. Laccases are a subfamily of multicopper oxidases involved in lignin depolymerization. Although they have been extensively characterized in fungi, studies of the diversity and functions of laccases in prokaryotes are mainly on enzyme isoforms of Streptomyces sp. In this work we isolated 20 strains of soil actinomycetes. The laccase activity of 17 of them was evidenced in qualitative assays with guaiacol, and two selected strains were characterized in detail. The morphological evidence and the analysis of the 16S rRNA gene sequences suggest that these two isolates belong to the genera Tsukamurella and Cellulosimicrobium. In submerged cultures with shaking, AC01 (Tsukamurella sp.) exhibited a maximal oxidation activity of ABTS (2,2 '-azino-bis-(3-ethylbenzthiazoline-6-sulfonate) of 108 U/L. On the other hand, AC18 (Cellulosimicrobium sp.) that exhibited a higher oxidative activity of guaiacol than the other 16 isolated strains and showed resistance to toxic levels of copper, reached a maximum ABTS oxidation rate of 0.56 U/L. These results suggest that in AC18 operates a mechanism of substrate or inducer specificity, regulating the measurable laccase activity and laccase gene expression. Genomic and functional characterization of laccases of new ligninolytic actinomycetes may help to extend the range of redox centers with specific biotechnological applications, as well as establishing their evolutionary relationships with eukaryotes.


Assuntos
Actinobacteria , Enzimas , Lacase , Lignina , Biomassa , Celulose , Fungos
19.
Braz. j. microbiol ; 43(4): 1545-1552, Oct.-Dec. 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-665842

RESUMO

Agro-industrial wastes such as sugarcane bagasse, wheat bran, rice bran, corn cob and wheat straw are cheapest and abundantly available natural carbon sources. The present study was aimed to production of amylase and xylanase simultaneously using agro-industrial waste as the sole carbon source. Seven thermophilic strains of actinomycete were isolated from the mushroom compost. Among of these, strain designated MSC702 having high potential to utilize agro-industrial wastes for the production of amylase and xylanase. Strain MSC702 was identified as novel species of Streptomyces through morphological characterization and 16S rRNA gene sequence. Enzyme production was determined using 1% (w/v) of various agro-industrial waste in production medium containing (g/100mL): K2HPO4(0.1), (NH4)2SO4(0.1), NaCl (0.1), MgSO4(0.1) at pH 7.0 after incubation of 48 h at 50°C. The amylase activity (373.89 IU/mL) and xylanase activity (30.15 IU/mL) was maximum in rice bran. The decreasing order of amylase and xylanase activity in different type of agro-industrial wastes were found rice bran (RB) > corn cob (CC) > wheat bran (WB) > wheat straw (WS) > sugarcane bagasse (SB) and rice bran (RB) > wheat bran (WB) > wheat straw (WS) > sugarcane bagasse (SB) > corn cob (CC), respectively. Mixed effect of different agro-industrial wastes was examined in different ratios. Enzyme yield of amylase and xylanase was ~1.3 and ~2.0 fold higher with RB: WB in 1:2 ratio.


Assuntos
Actinobacteria/isolamento & purificação , Amilases/análise , Amilases/isolamento & purificação , Sequência de Bases , Ativação Enzimática , Resíduos Industriais/análise , Streptomyces/isolamento & purificação , Xilanos/análise , Xilanos/isolamento & purificação , Microbiologia Industrial , Métodos
20.
Braz. j. microbiol ; 43(3): 909-916, July-Sept. 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-656652

RESUMO

The aim of the present study was to evaluate the presence of the periodontal pathogens that form the red complex (Tannerella forsythia, Porphyromonas gingivalis and Treponema denticola) and Aggregatibacter actinomycetemcomitans in patients with chronic periodontitis. The sample consisted of 29 patients with a clinical and radiographic diagnosis of chronic periodontitis based on the criteria of the American Academy of Periodontology (3). Samples for microbiological analysis were collected from the four sites of greatest probing depth in each patient, totaling 116 samples. These samples were processed using conventional polymerase chain reaction, which achieved the following positive results: 46.6% for P. gingivalis, 41.4% for T. forsythia, 33.6% for T. denticola and 27.6% for A. actinomycetemcomitans. P. gingivalis and T. forsythia were more prevalent (p < 0.05) in periodontal pockets ≥ 8 mm. The combinations T. forsythia + P. gingivalis (23.2%) and T. forsythia + P. gingivalis + T. denticola (20.0%) were more frequent in sites with a probing depth ≥ 8 mm. Associations with the simultaneous presence of A. actinomycetemcomitans + P. gingivalis, A. actinomycetemcomitans + T. forsythia, P. gingivalis + T. forsythia and T. forsythia + T. denticola were statistically significant (p < 0.05). It was concluded that the red complex pathogens are related to chronic periodontitis, presenting a higher occurrence in deep periodontal pockets. Moreover, the simultaneous presence of these bacteria in deep sites suggests a symbiotic relationship between these virulent species, favoring, in this way, a further progression of periodontal disease.


Assuntos
Humanos , Actinobacteria/isolamento & purificação , Actinobacteria/patogenicidade , Infecções Bacterianas , Técnicas In Vitro , Periodontite , Porphyromonas gingivalis/isolamento & purificação , Porphyromonas gingivalis/patogenicidade , Reação em Cadeia da Polimerase/métodos , Treponema denticola/patogenicidade , Métodos , Pacientes , Virulência
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