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1.
Rev. bras. parasitol. vet ; 28(3): 451-457, July-Sept. 2019. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-1042527

RESUMO

Abstract The msp4 gene of A. marginale is unicodon, stable and mostly homogeneous, being considered as a useful marker for phylogeographic characterization of this bacterium. The objective of this work was to analyze the phylogeography of A. marginale based on the msp4 gene in beef cattle from the Brazilian Pantanal, compared to those found in other regions worldwide. The blood samples investigated were collected from 400 animals (200 cows and 200 calves) reared in five extensive breeding farms in this region. The results indicated that of the evaluated samples, 56.75% (227/400) were positive for A. marginale based on the msp1β gene by quantitatitve PCR (qPCR), while 8.37% (19/227) were positive for the msp4 gene in the conventional PCR. In the Network distance analysis, 14 sequences from the Brazilian Pantanal were grouped into a single group with those from Thailand, India, Spain, Colombia, Parana (Brazil), Mexico, Portugal, Argentina, China, Venezuela, Australia, Italy and Minas Gerais (Brazil). Among 68 sequences from Brazil and the world, 15 genotypes were present while genotype number one (#1) was the most distributed worldwide. Both Splitstree and network analyses showed that the A. marginale msp4 sequences detected in beef cattle from the Brazilian Pantanal showed low polymorphism, with the formation of one genogroup phylogenetically related to those found in ruminants from South and Central America, Europe, and Asia.


Resumo O gene msp4 de A. marginale é unicodon, estável e pouco heterogêneo, sendo considerado como um marcador útil para caracterização filogeográfica desta bactéria. Este trabalho teve como objetivo analisar a filogeografia de A. marginale com base no gene msp4 em bovinos de corte do Pantanal Brasileiro, comparativamente a outra regiões do mundo. Alíquotas de sangue foram colhidas de 400 bovinos (200 vacas e 200 bezerros) em cinco propriedades de cria e recria extensiva. Como resultado, 56,75% (227/400) mostraram-se positivas para A. marginale pela qPCR para o gene msp1β e destas, 8,37% (19/227) amostras foram positivas na PCR convencional para o gene msp4. Na análise de distância Network, 14 sequências do Pantanal brasileiro foram agrupadas em um único grupo com as da Thailândia, Índia, Espanha, Colômbia, Paraná (Brasil), México, Portugal, Argentina, China, Venezuela, Austrália, Italia e Minas Gerais (Brasil). Dentre 68 sequências do Brasil e do mundo, constatou-se a presença de 15 genótipos, sendo o genótipo número um (#1) o mais distribuído. As sequências msp4 de A. marginale detectadas em bovinos de corte no Pantanal brasileiro apresentaram baixo polimorfismo com formação de dois genogrupos filogeneticamente relacionados àqueles encontrados em ruminantes de países das América do Sul e Central, Europa e Ásia.


Assuntos
Animais , Masculino , Feminino , Proteínas de Bactérias/genética , Bovinos/microbiologia , Anaplasma marginale/genética , Filogeografia/métodos , Proteínas de Membrana/genética , Ásia , América , Brasil , DNA Bacteriano/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sequência de Aminoácidos , Anaplasma marginale/isolamento & purificação , Europa (Continente) , Genótipo
2.
Rev. bras. enferm ; 72(3): 760-766, May.-Jun. 2019. tab
Artigo em Inglês | LILACS (Américas), BDENF | ID: biblio-1013564

RESUMO

ABSTRACT Objective: To evaluate the risk factors related to Klebsiella pneumoniae carbapenemase infection after renal transplantation. Methods: This was a retrospective epidemiological (case-control) study, conducted from October 2011 to march 2016. Transplanted patients with infection by this bacteria during hospitalization were selected as cases. The controls were paired by age, sex, type of donor and transplant time. The proportion of cases and controls was 1:2. Results: Thirty hundred and five patients were included in the study (45 cases and 90 controls). The risk factors found for infection by KPC were: time of hospitalization after the transplant (OR: 4.82; CI95% 2.46-9.44), delayed kidney function (OR: 5.60; CI95% 1.91-11.01) and previous infectious for another microorganism ( OR: 34.13 CI95% 3.52-132.00). Conclusion: The risk of acquisition of this bacterium was directly related to invasive procedures and exposure to the hospital environment. The findings reinforce the importance of prevention measures and control of infection by this microorganism.


RESUMEN Objetivo: Evaluar los factores de riesgo relacionados con la infección por Klebsiella pneumoniae carbapenemasa después del trasplante renal. Método: Estudio retrospectivo epidemiológico (caso-control), realizado de octubre de 2011 a marzo de 2016. Pacientes transplantados con infección por esa bacteria durante la internación fueron seleccionados como casos. Los controles se parearon por edad, sexo, tipo de donante y tiempo de trasplante. La proporción de casos y controles fue de 1: 2. Resultados: Treinta y cinco pacientes fueron incluidos en el estudio (45 casos y 90 controles). Los factores de riesgo para la infección encontrados por KPC fueron: tiempo de hospitalización después del trasplante (OR: 4,82, IC95% 2,46-9,44), función renal retardada (OR: 5,60, IC95% 1, 91-11,01) y anterior infecciosa para otro microorganismo (OR: 34,13 IC95% 3,52-132,00). Conclusión: El riesgo de adquisición de esta bacteria estuvo directamente relacionado a procedimientos invasivos y exposición al ambiente hospitalario. Los hallazgos refuerzan la importancia de medidas de prevención y control de la infección por ese microorganismo.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pneumonia/etnologia , Proteínas de Bactérias/efeitos adversos , beta-Lactamases/efeitos adversos , Infecções por Klebsiella/etiologia , Transplante de Rim/efeitos adversos , Pneumonia/induzido quimicamente , Pneumonia/epidemiologia , Proteínas de Bactérias/metabolismo , beta-Lactamases/metabolismo , Brasil/epidemiologia , Infecções por Klebsiella/metabolismo , Infecções por Klebsiella/epidemiologia , Estudos de Casos e Controles , Estudos Retrospectivos , Fatores de Risco , Transplante de Rim/métodos , Klebsiella pneumoniae/metabolismo , Klebsiella pneumoniae/patogenicidade , Pessoa de Meia-Idade
3.
Braz. j. biol ; 79(2): 248-256, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-989445

RESUMO

Abstract The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p <0.05) negatively with precipitation. This study provided field information on the abundance and species richness of owlet moths on non-Bt soybeans, associated with the effects of Bt soybean. When considering the different levels of infestation between cultivars as a criterion, larvae monitoring is of substantial importance in order to develop the lost control program.


Resumo O uso de OGM que expressam toxina Bt na produção de soja tem aumentado significativamente nos últimos anos no Brasil e são utilizados para conter os danos causados ​​pelos lepidópteros pragas. Neste estudo comparamos a riqueza e a abundância de Noctuoides (Noctuoidea) associados à soja Bt e não-Bt. Determinamos as variações temporais em função da fenologia e correlacionamos às variações populacionais das espécies mais comuns com variáveis ​​meteorológicas. A pesquisa foi conduzida na área experimental da Embrapa Cerrados. O método de coleta utilizado foi diferenciado sendo supressivo e absoluto. Um total de 13 espécies foram coletadas, das quais oito ocorreram em soja Bt. Os taxa mais representativos foram Chrysodeixis includens, Anticarsia gemmatalis e Spodoptera spp. O número de larvas pertencentes às espécies alvo da tecnologia Bt foram 10 vezes menores na soja Bt do que em soja não-Bt . Utetheisa ornatrix e Elaphria deltoides foram registradas na soja pela primeira vez, observando-se larvas de ambas espécies na soja não-Bt e as de U. ornatrix também na soja Bt. Somente as larvas de A. gemmatalis se correlacionaram (p <0,05) negativamente com a precipitação. Este estudo forneceu informações em campo sobre a abundância e riqueza de espécies na soja não- Bt, associada aos efeitos da soja Bt. A importância do monitoramento das lagartas é substancial, a fim de tomar a melhor decisão de controle, considerando-se os diferentes níveis de infestação entre cultivares como critério.


Assuntos
Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Soja/genética , Soja/parasitologia , Brasil , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos
4.
Chinese Journal of Biotechnology ; (12): 558-566, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771353

RESUMO

Bacterial biofilm refers to a tunicate-like biological group composed of polysaccharide, protein and nucleic acid secreted by bacteria on the surface of the mucous membrane or biological material. The biofilm formation is a major cause of chronic infections. Bacteria could produce some secondary metabolites during the growth and reproduction. Some of them act as signaling molecules allowing bacteria to communicate and regulate many important physiological behaviors at multiple-cell level, such as bioluminescence, biofilm formation, motility and lifestyles. Usually, these signal molecules play an important role in the formation of bacterial biofilm. We review here the effects of related signal molecules of Quorum Sensing, cyclic diguanylate, Two-Component Systems and sRNA on the biofilm formation. Focusing on these regulation mechanism of signal molecules in the process of biofilm formation is necessary for the prevention and treatment of some chronic diseases.


Assuntos
Proteínas de Bactérias , Biofilmes , GMP Cíclico , Regulação Bacteriana da Expressão Gênica , Ligação Proteica , Percepção de Quorum
5.
Chinese Journal of Biotechnology ; (12): 718-725, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771338

RESUMO

Multi-epitope recombinant diagnostic antigen (designated 'B102') of Mycobacterium tuberculosis (Mtb) was prepared and evaluated as a serological diagnostic antigen. With TRX at the N-terminal and His tag at the C-terminal, the multi-epitope Mtb recombinant diagnostic antigen including 11 predicted B-cell epitopes from 6 Mtb antigens (PstS1, ESAT6, CFP10, Ag85B, Ag85A and PPE54) was expressed in Escherichia coli BL21 (DE3) and purified by Ni²⁺-Chelating affinity and DEAE anion exchange chromatography. Based on the antigenicity of B102 confirmed in Western blotting analysis, we constructed and evaluated a double-antigen sandwich ELISA for diagnosis of Mtb infection. The protein B102 exists in the form of inclusion bodies, accounting for 31.25% of the total proteins of the bacteria. After purification and renaturation, protein B102 exists in soluble form with the concentration 3.124 mg/mL and the homogeneity 96.71%. WB analysis demonstrated that protein B102 could react with antibodies in Mtb positive serum. Using the novel antigen in ELISA, we tested 60 Mtb-related positive and negative serum; The results showed the sensitivity, specificity, positive and negative predictive values and coincidence rate of the detection method is 90.00%, 93.33%, 93.10%, 90.32% and 91.67%, respectively. The McNemer analysis suggested there was no statistical difference between the 'Gold standard' and the novel ELISA with kappa 0.833, which suggested the excellent consistency. By prokaryotic expression and chromatography purification, the multi-epitope recombinant antigen B102 was obtained with excellent antigenicity, which could be applied for Mtb-related serological detection.


Assuntos
Antígenos de Bactérias , Proteínas de Bactérias , Western Blotting , Ensaio de Imunoadsorção Enzimática , Epitopos , Escherichia coli , Mycobacterium tuberculosis
6.
Chinese Journal of Biotechnology ; (12): 795-804, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771330

RESUMO

The cyanobacterial circadian clock has three relatively independent parts: the input path, the core oscillator, and the output path. The core oscillator is composed of three clock proteins: KaiA, KaiB, and KaiC. The interactions among these three proteins generate a rhythmic signal and convey the input signals to the output signals to maintain the accuracy and stability of the oscillation of downstream signals. Based on the cyanobacterial circadian clock and the structure, function, and interaction of the clock proteins of the core oscillator, combining the recent results from our laboratory, this review summarized the recent progresses of the molecular mechanism of KaiA in regulating KaiC's enzymatic activity, mediating phase reset of the oscillator, and competing with CikA for the binding site of KaiB.


Assuntos
Proteínas de Bactérias , Genética , Metabolismo , Relógios Circadianos , Genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano , Metabolismo , Cianobactérias , Genética , Ativação Enzimática , Genética
7.
Chinese Journal of Biotechnology ; (12): 847-856, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771325

RESUMO

Pectobacterium carotovorum subsp. carotovorum is one of the world's top ten plant pathogens, mainly infecting cruciferous economic crops and ornamental flowers. In this study, an antibacterial gene cpxP (Gene ID: 29704421) was cloned from the genome of Pectobacterium carotovorum subsp. carotovorum, and constructed on the prokaryotic expression plasmid pET-15b, and the recombinant plasmid was transformed into Escherichia coli BL21 (DE3), then stability and bacteriostatic experiments of the purified CpxP protein were performed. The final concentration of IPTG was 1 mmol/L, obtaining high-efficiency exogenous expression of the CpxP protein. There was no other protein after purification, and the destined protein exhibited good thermal stability and pH stability. The antibacterial test results showed that the inhibition rate of the CpxP protein on carrot slice was 44.89% while the inhibition rate on potato slice was 59.41%. To further explain its antibacterial mechanism, studying the spatial structure of this protein can provide new ideas for the control of soft rot and new protein pesticide targets.


Assuntos
Antibacterianos , Farmacologia , Bactérias , Proteínas de Bactérias , Farmacologia , Escherichia coli , Genética , Proteínas de Membrana , Farmacologia , Pectobacterium carotovorum , Genética , Metabolismo , Plasmídeos , Genética
8.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-773376

RESUMO

OBJECTIVE@#To investigate the molecular characteristics and intracellular growth ability of Legionella pneumophila (L. pneumophila) strains from 1989 to 2016 in Sichuan Province, China.@*METHODS@#Seventy-nine isolates of L. pneumophila were collected from environmental and clinical sources, including cooling towers, hot springs, bath water, fountains, and patients, and identified with 16S rRNA gene analysis and serum agglutination assay. The isolates were then typed by Sequence-Based Typing (SBT), and Genotyping of forty-two LP1 strains were analyzed by means of multiple-locus VNTR analysis with 8 loci (MLVA-8). All strains were further analyzed for two virulence genes: Legionella vir homologue (lvh) and repeats in structural toxin (rtxA). The intracellular growth ability of 33 selected isolates was determined by examining their interaction with J774 cells.@*RESULTS@#All isolates were identified to L. pneumophila including 11 serogroups, among which the main serogroup were LP1, accounting for 54.43%. Thirty-three different sequence types (STs) from five main clonal groups and five singletons were identified, along with 8 different MLVA patterns. Both the lvh and rtxA loci were found in all 79 strains. Thirty isolates showed high intracellular growth ability in J774 cells.@*CONCLUSION@#L. pneumophila is a potential threat to public health, and effective control and prevention strategies are urgently needed.


Assuntos
Proteínas de Bactérias , Genética , Toxinas Bacterianas , Genética , China , Técnicas de Genotipagem , Humanos , Legionella pneumophila , Genética , RNA Ribossômico 16S , Genética , Microbiologia da Água
9.
Chinese Journal of Biotechnology ; (12): 1117-1125, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771816

RESUMO

To prepare polyclonal antibody (PcAb) against Escherichia coli filamentous thermosensitive protein Z (Ec-FtsZ), the artificially synthesized gene fragment coding Ec-FtsZ was subcloned into pET-22b(+) plasmid, and Ec-FtsZ protein was expressed in E. coli BL21(DE3) cell under an optimal bacterial expression condition. Then Ec-FtsZ protein was purified by HisTrap affinity chromatography, and the GTPase (Guanosine triphosphatase) activity of purified Ec-FtsZ protein was further analyzed by malachite green assay. Subsequently, the purified Ec-FtsZ protein was used to immunize rat subcutaneously for preparation of anti-Ec-FtsZ PcAb. The results of enzyme-linked immunosorbent assay (ELISA), Western blotting analysis and immunofluorescence assay showed that the titer of PcAb was 1:256 000, and PcAb exhibited a perfect antigenic specificity against purified and endogenous Ec-FtsZ protein. All these data indicated that the anti-Ec-FtsZ PcAb is successfully prepared, which can be used for further cellular function study and biochemical analysis of Ec-FtsZ protein in vivo.


Assuntos
Animais , Anticorpos , Especificidade de Anticorpos , Proteínas de Bactérias , Western Blotting , Proteínas do Citoesqueleto , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Plasmídeos , Ratos
10.
Chinese Journal of Biotechnology ; (12): 1500-1510, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771779

RESUMO

MarR family transcription regulators are ubiquitous among bacteria and archaea. They extensively control multiple cellular processes and elaborately regulate the expression of genes involved in virulence, stress response and antibiotics at translational level. In Xanthomonas campestris pv. campestris, insertional inactivation of MarR family transcription regulator HpaR (XC2827) resulted in significantly decrease in virulence and increase in the production of the extracellular proteases. Here, we reported that the genome of Xcc 8004 encodes nine MarR family transcription regulators. The MarR family transcription regulators, HpaR (XC2827) and XC0449, were heterologous expressed and purified. In vitro MST and Pull-down assay confirmed the physical interaction between HpaR and XC0449. Phenotypical assay determined that deletion of XC0449 resulted in substantial virulence attenuation. In vitro EMSA, in vivo qRT-PCR and GUS activity assay identified that HpaR and XC0449 coordinately act as the transcriptional activator to regulate the expression of the virulence-associated gene XC0705, and eventually control the bacterial virulence and the production of extracellular proteases.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Fatores de Transcrição , Virulência , Xanthomonas campestris
11.
Chinese Journal of Biotechnology ; (12): 1511-1519, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771778

RESUMO

With the rapid development of transgenic technology, the safety of genetically modified products has received extensive attention. Certified reference materials for the detection of genetically modified organisms play important roles in ensuring comparability and traceability of the qualitative and quantitative detection of genetically modified products. However, the development of protein reference materials is relatively slow, and one of the difficulties is the preparation of protein candidates with high purity. The cry1Ah1 gene of Bacillus thuringiensis has been used for the development of transgenic insect-resistant crops because of its excellent insecticidal activity against lepidopteran pests such as Asian corn borer, and has obtained transgenic lines with good insect resistance traits. In order to develop Cry1Ah protein certified reference material, it is urgent to establish a preparation and purification system. In this study, a system for preparing Cry1Ah protein by Bt expression system was optimized, and a high-purity Cry1Ah protein (size exclusion chromatography purity: 99.6%) was obtained by ion-exchange chromatography and size exclusion chromatography stepwise purification. The results of biological activity assay showed that there was no significant difference in the insecticidal activity of purified Cry1Ah protein and protoxin against diamondback moths (Plutella xylostella). Finally, the amino acid sequence of the activated Cry1Ah protein was determined using Edman degradation and mass spectrometry. In summary, the obtained Cry1Ah pure protein can be used for the development of protein reference materials.


Assuntos
Animais , Bacillus thuringiensis , Proteínas de Bactérias , Criptocromos , Metabolismo , Endotoxinas , Proteínas Hemolisinas , Mariposas , Controle Biológico de Vetores , Plantas Geneticamente Modificadas
12.
Chinese Journal of Biotechnology ; (12): 1662-1675, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771764

RESUMO

The fcl gene encodes GDP-fucose synthase, which catalyzes two-step differential isomerase and reductase reactions in the synthesis of GDP-L-fucose from GDP-D-mannose. It also participates in the biosynthesis of amino sugar and ribose sugar, and is one of the key enzymes to regulate the metabolism of sugar and nucleotides in organisms. The presence of fcl gene in Saccharopolyspora pogona was found through sequencing result of genome. The mutant S. pogona-fcl and S. pogona-Δfcl were constructed by gene engineering technology. The results showed that the gene had an effects on growth and development, protein expression and transcriptional level, insecticidal activity, and biosynthesis of butenyl-spinosyn of Saccharopolyspora pogona. The results of HPLC analysis showed that the yield of butenyl-spinosyn in S. pogona-Δfcl was 130% compared with that in S. pogona, which reduced by 25% in S. pogona-fcl. The results of determination of insecticidal activity showed that S. pogona-Δfcl had a stronger insecticidal activity against Helicoverpa armigera than that of S. pogona, while the S. pogona-fcl had a lower insecticidal activity against Helicoverpa armigera compared with S. pogona. Scanning electron microscopy (SEM) was used to observe the morphology of the mycelia. It was found that the surface of the S. pogona-Δfcl was wrinkled, and the mycelium showed a short rod shape. There was no significant difference in mycelial morphology between S. pogona-fcl and S. pogona. Aboved all showed that deletion of fcl gene in S. pogona hindered the growth and development of mycelia, but was beneficial to increase the biosynthesis of butenyl-spinosyn and improve insecticidal activity. Whereas the fcl gene over-expression was not conducive to the biosynthesis of butenyl-spinosyn and reduced their insecticidal activity. SDS-PAGE results showed that the difference of protein expression among the three strains was most obvious at 96 hours, which was identified by real-time fluorescence quantitative polymerase chain reaction, the results showed that there were significant differences of related genes in transcriptional levels among the three strains. Based on the results of the study, a network metabolic control map was constructed to analyze the effect of fcl gene on growth and the regulation pathway of butenyl-spinosyn biosynthesis, which provided an experimental basis for revealing the regulation mechanism of butenyl-spinosyn biosynthesis and related follow-up studies.


Assuntos
Proteínas de Bactérias , Engenharia Genética , Inseticidas , Macrolídeos , Saccharopolyspora
13.
Chinese Journal of Biotechnology ; (12): 204-215, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771386

RESUMO

Urease decomposes urea to ammonia, and has application potential in agriculture and medical treatment. Urease proteins include structural proteins (UreA, UreB and UreC) and accessory proteins (UreD/UreH, UreE, UreF and UreG), each of them has its own unique role in urease maturation. The structural proteins form the active center of urease, and the accessory proteins are responsible for the delivery of nickel. We review here the structure and function of bacterial urease complexes, and how each protein interacts to complete the activation process. We hope to provide theoretical basis for the regulation of urease activity and the development of urease inhibitors.


Assuntos
Proteínas de Bactérias , Níquel , Urease , Metabolismo
14.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-776863

RESUMO

Three new phenazine-type compounds, named phenazines SA-SC (1-3), together with four new natural products (4-7), were isolated from the fermentation broth of an earwig-associated Streptomyces sp. NA04227. The structures of these compounds were determined by extensive analyses of NMR, high resolution mass spectroscopic data, as well as single-crystal X-ray diffraction measurement. Sequencing and analysis of the genome data allowed us to identify the gene cluster (spz) and propose a biosynthetic pathway for these phenazine-type compounds. Additionally, compounds 1-5 exhibited moderate inhibitory activity against acetylcholinesterase (AChE), and compound 3 showed antimicrobial activities against Micrococcus luteus.


Assuntos
Animais , Antibacterianos , Química , Metabolismo , Farmacologia , Proteínas de Bactérias , Genética , Metabolismo , Cristalografia por Raios X , Insetos , Microbiologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Micrococcus luteus , Estrutura Molecular , Família Multigênica , Fenazinas , Química , Metabolismo , Farmacologia , Streptomyces , Química , Genética , Metabolismo
15.
Braz. j. microbiol ; 49(4): 914-918, Oct.-Dec. 2018. tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-974286

RESUMO

ABSTRACT The global emergence of carbapenemases led to the need of developing new methods for their rapid detection. The aim of this study was to evaluate the performance of the rapid tests for carbapenemase-producing and non-producing Enterobacteriaceae. Carbapenem non-susceptible Enterobacteriaceae from a surveillance study submitted to a multiplex real time PCR for carbapenemase detection were included in this study. The isolates were subjected to the rapid phenotypic tests Carba NP, Blue-Carba and Carbapenem Inactivation Method (CIM). A total of 83 carbapenemase-producing (43) and non-producing (40) isolates were included in the study. The sensitivity/specificity were 62.7%/97.5%, 95.3%/100%, and 74.4%/97.5% for Carba NP, Blue-Carba and CIM, respectively. Both Carba NP and Blue-Carba presented their final results after 75 min of incubation; the final results for CIM were obtained only after 8 h. Failure to detect OXA-370 carbapenemase was the main problem for Carba NP and CIM assays. As the Blue-Carba presented the highest sensitivity, it can be considered the best screening test. Conversely, CIM might be the easiest to perform, as it does not require special reagents. The early detection of carbapenemases aids to establish infection control measures and prevent carbapenemases to spread reducing the risk of healthcare associated infections and therapeutic failure.


Assuntos
Humanos , Proteínas de Bactérias/análise , beta-Lactamases/análise , Enterobacteriaceae/enzimologia , Infecções por Enterobacteriaceae/microbiologia , Ensaios Enzimáticos/métodos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , beta-Lactamases/genética , beta-Lactamases/metabolismo , Brasil , Carbapenêmicos/farmacologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/diagnóstico , Antibacterianos/farmacologia
16.
Braz. j. microbiol ; 49(4): 731-741, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-974291

RESUMO

ABSTRACT A bacterium isolated from Sterkfontein dam was confirmed to produce bioflocculant with excellent flocculation activity. The 16S rDNA nucleotide sequence analyses revealed the bacteria to have 99% similarity to Streptomyces platensis strain HBUM174787 and the sequence was deposited in the Genbank as Streptomyces platensis with accession number FJ 486385.1. Culture conditions for optimal production of the bioflocculant included glucose as a sole carbon source, resulting in flocculating activity of 90%. Other optimal conditions included: peptone as nitrogen source; presence of Mg2+ as cations and inoculum size of 1.0% (v/v) at neutral pH of 7. Optimum dose of the purified bioflocculant for the clarification of 4 g/L kaolin clay suspension at neutral pH was 0.2 mg/mL. Energy Dispersive X-ray analysis confirmed elemental composition of the purified bioflocculant in mass proportion (%w/w): carbon (21.41), oxygen (35.59), sulphur (26.16), nitrogen (0.62) and potassium (7.48). Fourier Transform Infrared Spectroscopy (FTIR) indicated the presence of hydroxyl, carboxyl, methoxyl and amino group in the bioflocculant. The bioflocculant produced by S. platensis removed chemical oxygen demand (COD) in river water and meat processing wastewater at efficiencies of 63.1 and 46.6% respectively and reduced their turbidity by 84.3 and 75.6% respectively. The high flocculating rate and removal efficiencies displayed by S. platensis suggests its industrial application in wastewater treatment.


Assuntos
Streptomyces/química , Proteínas de Bactérias/metabolismo , Águas Residuárias/química , Streptomyces/isolamento & purificação , Streptomyces/genética , Streptomyces/metabolismo , Proteínas de Bactérias/genética , Microbiologia da Água , Carbono/metabolismo , Purificação da Água , Rios/química , Floculação , Nitrogênio/metabolismo
17.
Braz. j. microbiol ; 49(4): 848-855, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-974300

RESUMO

ABSTRACT We studied the role of Thermus thermophilus Recombinase A (RecA) in enhancing the PCR signals of DNA viruses such as Hepatitis B virus (HBV). The RecA gene of a thermophilic eubacterial strain, T. thermophilus, was cloned and hyperexpressed in Escherichia coli. The recombinant RecA protein was purified using a single heat treatment step without the use of any chromatography steps, and the purified protein (>95%) was found to be active. The purified RecA could enhance the polymerase chain reaction (PCR) signals of HBV and improve the detection limit of the HBV diagnosis by real time PCR. The yield of recombinant RecA was ∼35 mg/L, the highest yield reported for a recombinant RecA to date. RecA can be successfully employed to enhance detection sensitivity for the diagnosis of DNA viruses such as HBV, and this methodology could be particularly useful for clinical samples with HBV viral loads of less than 10 IU/mL, which is interesting and novel.


Assuntos
Proteínas de Bactérias/genética , Vírus da Hepatite B/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Thermus thermophilus/enzimologia , Clonagem Molecular , Recombinases/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Expressão Gênica , Vírus da Hepatite B/genética , Reação em Cadeia da Polimerase/instrumentação , Thermus thermophilus/genética , Recombinases/isolamento & purificação , Recombinases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
18.
Braz. j. microbiol ; 49(4): 885-890, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-974312

RESUMO

ABSTRACT In this study, the performance of the "RESIST-3 O.K.N. K-SeT" (Coris BioConcept, Gembloux, Belgium) immunochromatographic assay was evaluated in 132 Klebsiella pneumoniae comprising 102 carbapenem resistant and 30 carbapenem susceptible isolates. Genotypically known isolates of Gram negative bacteria (n = 22) including various species were also tested by the assay as controls. The isolates tested by the immunochromatographic assay and also were run PCR for bla KPC, bla IMP, bla VIM, bla NDM, and bla OXA-48. The rates of bla NDM, bla OXA-48, and bla KPC in carbapenem resistant isolates were found at 52.9%, 39.2%, and 2.0%, respectively. Both bla NDM and bla OXA-48 were found in six (5.9%) isolates. The results of the assay showed 100% concordance with those obtained by PCR in 132 K. pneumoniae. The agreement between the two methods was found to be identical at the isolate level. The assay also correctly detected all genotypically known isolates of Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter cloacae, K. pneumoniae carrying bla KPC, bla NDM, and/or bla OXA-48. On the other hand, the assay did not exhibit any cross-reaction in control isolates harboring bla IMP and bla VIM. We conclude that the RESIST-3 O.K.N. K-SeT is a reliable, rapid, and user friendly test and we recommend it for routine diagnostic laboratories.


Assuntos
Humanos , Proteínas de Bactérias/análise , beta-Lactamases/análise , Infecções por Klebsiella/microbiologia , Imunoensaio/métodos , Klebsiella pneumoniae/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Turquia , beta-Lactamases/metabolismo , Carbapenêmicos/farmacologia , Reação em Cadeia da Polimerase , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/química , Antibacterianos/farmacologia
19.
Braz. j. microbiol ; 49(3): 601-606, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-951806

RESUMO

Abstract Salmonella Gallinarum is a host-restrict pathogen that causes fowl typhoid, a severe systemic disease that is one of the major concerns to the poultry industry worldwide. When infecting the bird, SG makes use of evasion mechanisms to survive and to replicate within macrophages. In this context, phoPQ genes encode a two-component regulatory system (PhoPQ) that regulates virulence genes responsible for adaptation of Salmonella spp. to antimicrobial factors such as low pH, antimicrobial peptides and deprivation of bivalent cations. The role of the mentioned genes to SG remains to be investigated. In the present study a phoPQ-depleted SG strain (SG ΔphoPQ) was constructed and its virulence assessed in twenty-day-old laying hens susceptible to fowl typhoid. SG ΔphoPQ did cause neither clinical signs nor mortality in birds orally challenged, being non-pathogenic. Furthermore, this strain was not recovered from livers or spleens. On the other hand, chickens challenged subcutaneously with the mutant strain had discreet to moderate pathological changes and also low bacterial counts in liver and spleen tissues. These findings show that SG ΔphoPQ is attenuated to susceptible chickens and suggest that these genes are important during chicken infection by SG.


Assuntos
Animais , Feminino , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Proteínas de Bactérias/genética , Salmonella enterica/metabolismo , Salmonella enterica/patogenicidade , Inativação Gênica , Doenças das Aves Domésticas/patologia , Salmonelose Animal/patologia , Baço/microbiologia , Baço/patologia , Proteínas de Bactérias/metabolismo , Virulência , Galinhas , Salmonella enterica/genética
20.
Braz. j. microbiol ; 49(3): 668-674, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-951814

RESUMO

Abstract The virulence genes in invasive aspergillosis (IA) have not been analyzed adequately. The present study was designed to evaluate the expression of gpaB and sidA genes, which are important virulence genes in Aspergillus spp. from bronchoalveolar lavage (BAL) samples. Direct examination and culture on Czapek Agar and Sabouraud Dextrose Agar media were performed for 600 BAL specimens isolated from patients with possible aspergillosis. A Galactomannan ELISA assay was also carried out. The expression levels of the gpaB and sidA genes in isolates were analyzed using quantitative real-time PCR (qRT-PCR). We identified 2 species, including Aspergillus flavus (A. flavus) and Aspergillus fumigatus (A. fumigatus) in 25 positive samples for invasive aspergillosis as validated using GM-ELISA. A. flavus is the main pathogen threatening transplant recipients and cancer patients worldwide. In this study, A. flavus had low levels of the gpaB gene expression compared to A. fumigatus (p = 0.006). The highest sidA expression was detected in transplant recipients (p = 0.05). There was no significant correlation between sidA expression and underlying disease (p = 0.15). The sidA and gpaB gene expression patterns may provide evidence that these virulence genes play important roles in the pathogenicity of Aspergillus isolates; however, there are several regulatory genes responsible for the unexpressed sidA and gpaB genes in the isolates.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Aspergilose/microbiologia , Aspergillus flavus/metabolismo , Aspergillus flavus/patogenicidade , Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/patogenicidade , Proteínas de Bactérias/metabolismo , Aspergillus flavus/isolamento & purificação , Aspergillus flavus/genética , Aspergillus fumigatus/isolamento & purificação , Aspergillus fumigatus/genética , Proteínas de Bactérias/genética , Virulência
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