Papers by José Daniel Vieira
Enciclopédia Biosfera
RESUMO A biomineralização é uma alteração química em um ambiente através de atividade microbiana ... more RESUMO A biomineralização é uma alteração química em um ambiente através de atividade microbiana que resulta na precipitação de minerais, sendo um fenômeno amplamente distribuído na natureza. Na precipitação de carbonato de cálcio induzida microbiologicamente (MICP, do inglês microbially induced calcium carbonate precipitation), a urease apresenta papel importante ao hidrolisar a ureia, por uma grande variedade de micro-organismos capazes de produzir elevados níveis desta enzima. Existem diferentes polimorfos do cristal de carbonato de cálcio e a estrutura que é formada depende do tipo da fonte de cálcio utilizada, período de incubação e atividades metabólicas referentes à espécie microbiana avaliada. A MICP é uma alternativa promissora e ambientalmente amigável para as tecnologias de remediação atuais e convencionais capazes de resolverem problemas ambientais em campos multidisciplinares. Várias aplicações como aumento da qualidade e da melhoria das propriedades de materiais de construção, remoção de metais potencialmente tóxicos e radionucleotídeos e sequestro de dióxido de carbono atmosférico têm sido discutidas. PALAVRAS-CHAVE: Biomoneralização, carbonato de cálcio, construção civil, MICP, urease. CALCIUM CARBONATE BIOPRECIPITATION BY UREOLYTIC BACTERIA AND ITS APPLICATIONS ABSTRACT Biomineralization is a chemical change in environment through the microbial activity that results in the precipitation of minerals, being a phenomenon widely spread in nature. In microbially induced carbonate precipitation (MICP), ureases plays an important role in hydrolyzing urea by a large variety of microorganisms capable of producing high levels of this enzyme. There are different polymorphs of calcium carbonate crystal and the structure that is formed depends on the type of calcium used, the incubation time and metabolic activities of the evaluated microbrial species.
Phytopathology®, 2015
The fungus Rhizoctonia solani anastomosis group (AG)-1 IA emerged in the early 1990s as an import... more The fungus Rhizoctonia solani anastomosis group (AG)-1 IA emerged in the early 1990s as an important pathogen causing foliar blight and collar rot on pastures of the genus Urochloa (signalgrass) in South America. We tested the hypothesis that this pathogen emerged following a host shift or jump as a result of geographical overlapping of host species. The genetic structure of host and regional populations of R. solani AG-1 IA infecting signalgrass, rice, and soybean in Colombia and Brazil was analyzed using nine microsatellite loci in 350 isolates to measure population differentiation and infer the pathogen reproductive system. Phylogeographical analyses based on the microsatellite loci and on three DNA sequence loci were used to infer historical migration patterns and test hypotheses about the origin of the current pathogen populations. Cross pathogenicity assays were conducted to measure the degree of host specialization in populations sampled from different hosts. The combined ana...
Brazilian Journal of Microbiology
Helicobacter pylori is the etiological agent of chronic gastritis, peptic ulcer, and gastric canc... more Helicobacter pylori is the etiological agent of chronic gastritis, peptic ulcer, and gastric cancer. The duodenal ulcer-promoting gene dupA, which is located in the plasticity region of the H. pylori genome, is homologous to the virB gene which encodes a type IV secretion protein in Agrobacterium tumefaciens. Studies have shown associations between H. pylori dupA-positive strains and gastroduodenal diseases. However, whether dupA acts as a risk factor or protective factor in these diseases remains unclear. Therefore, in this study, we aimed to verify the presence of the dupA gene in infectious H. pylori strains in the Brazilian mid-west and to investigate its association with the clinical outcomes of patients with dyspepsia. Additionally, the phylogenetic origin of the strains was determined. Gastric biopsies from 117 patients with dyspepsia were analyzed using histological and molecular techniques. The hpx gene (16S rRNA) was used to screen for H. pylori infection, and positive samples were then subjected to dupA gene detection and sequencing. The estimated prevalence of H. pylori infection was 64.1%, with the dupA gene being detected in a high proportion of infectious strains (70.7%). Furthermore, a risk analysis revealed that for women, a dupA-positive H. pylori infection increased the chance of developing gastritis by twofold. The partial dupA sequences from isolated infectious strains in this work are similar to those of strains isolated in westerns countries. This study provides useful insights for understanding the role of the H. pylori dupA gene in disease development.
Research, Society and Development
The Meia Ponte River – Goiás/Brazil, is responsible for benefiting about 2 million people in Goiá... more The Meia Ponte River – Goiás/Brazil, is responsible for benefiting about 2 million people in Goiás State. However, the increase in pollution with the disposal of sewage, chemicals and drug remains have contributed to the increase in bacterial resistance and the exchange of resistance genes. The objective of this study was to isolate, identify and analyze the resistance profile of gram-positive bacteria present in raw water and sediment of the Meia Ponte River – Goiás. The samples were collected from four sampling points and two collections were carried out, one in the dry season and the other in the rainy season. The isolated bacteria were identificated, then the antibiogram was performed. A total of 75 strains were isolated, 72.0% (54/75) of Streptococcus spp., 12.0% (9/75) of Staphylococcus spp., 9.3% (7/75) of Bacillus spp. and 6.7% (5/75) of Enterococcus spp. Furthermore, 52.0% (39/75) of the isolated strains were from raw water and 48.0% (36/75) were isolated from the sediment....
Enciclopédia Biosfera
E cada vez mais presente pesquisas com microrganismos endofiticos produtores dediferentes metabol... more E cada vez mais presente pesquisas com microrganismos endofiticos produtores dediferentes metabolitos, tais como as enzimas hidroliticas, que apresentam grandeaplicabilidade nos processos industriais, devido a sua ampla variedade de estruturae de aplicacoes, alta especificidade e estabilidade, baixo impacto ao meio ambiente,possibilidade de producao em grande escala em curto periodo de tempo e combaixo custo. O presente estudo teve como objetivo isolar bacterias endofiticas deTridax procumbens (L.) e avaliar a producao de enzimas hidroliticas produzidas poressas bacterias. Um total de oito bacterias endofiticas, de diferentes partes da plantaforam selecionadas e analisadas quanto a sua capacidade de sintese das enzimasamilase, β-glucosidase, celulase, endoglucanase, esterase, exoglucanase, lipase,pectinase, protease e xilanase, usando meios de cultura solidos especificos paraproducao de cada enzima. Das oito bacterias isoladas, todas apresentaram atividadepectinolitica e proteolitica, 87,5% atividade β-glucosidase e celulolitica (cana-de- acucar), 75% atividade endoglucanase e exoglucanase, 62,5% atividade xilanase, 50% atividade amilolitica, 37,5% atividade celulolitica (bambu) e esterasica, nenhuma apresentou atividade lipasica. Em conclusao, os isolados exibem potencial como produtores de enzimas hidroliticas de interesse industrial.
Revista de Biología Tropical
Phyllomedusa azurea is a frog species well distributed geographically in South America, including... more Phyllomedusa azurea is a frog species well distributed geographically in South America, including Brazilian biomes as Pantanal and Cerrado. Compared with other anurans from the Phyllomedusinae family, there are few reports on the bioactive potential of skin-derived molecules from this species. In this perspective, the aim of the present study was to evaluate the in vitro antibacterial activity of skin secretion of P. azurea by detection of Minimum Inhibitory Concentration (MIC) of the growth of bacterial indicator strains and to determine if occurs a changing in the bacterial cell envelope permeability. The MIC determination was carried out by the microdilution plate method. The absorbance was measured and analyzed statistically using the t-test to compare two groups (0.05 % of significance). The impact of the crude extract on cell envelope permeability of Staphylococcus aureus ATCC 25923 was conducted by the crystal violet assay, and the absorbance was measured spectrophotometry fo...
Enciclopédia Biosfera, Dec 5, 2017
Gossypium hirsutum L. consists in the most cultivated cotton species worldwide, exhibiting signif... more Gossypium hirsutum L. consists in the most cultivated cotton species worldwide, exhibiting significative historical and economical importance, mainly in the American continent. Beyond common plagues that widely affect cotton, it is known that the plant exhibits a diverse symbiotic microbial community. Endophytic microorganisms are defined as those that spend part or the entire life period colonizing asymptotically plant tissues and, by several mechanisms, can promote the host growth and participate in its protection against pathogens. The aim of the actual work was the isolation and qualitative evaluation of various biotechnological potentialities of endophytic bacteria isolates from cotton leaves. Nine bacterial morphotypes were isolated, with 77,7% exhibiting positivity for at least one of the screening tests. The same percentage of isolates (77,7%) was capable to produce indole-acetic-acid (IAA), 66,6% solubilized phosphate and 55,5% grew in a free-nitrogen medium. Two isolates, AL1 and AL8, generated extracellularly exoenzymes and only one morphotype, AL1, was able to inhibit the growth of one of the applied bacterial standard strains. The results are promising for the conduction of future studies that will consolidate these possible applications of the endophytic bacteria from cotton under the most different areas in the biotechnological field.
International Journal of Microbiology Research
Rhizospheric actinobacteria associated to organic cultivation are essential in nutrient cycling a... more Rhizospheric actinobacteria associated to organic cultivation are essential in nutrient cycling and plant growth promotion. The aim of thi s study was to isolate and select in vitro actinobacteria displaying multiple plant growth promoting traits associated with the rhizosphere of sugarcane undergoing organic management. The isolates were evaluated regarding their ability to produce plant growth promoting traits. Of the 21 isolates, 57% produced at least one of the evaluated traits. Isolates ABC92 and ABC32 produced 60.28 and 55.36 μg mL-1 of fitohormone in 21 days, whereas isolates ANC48 and ANU34 were the best solubilizers, solubilizing 8.93 and 8.92 μg mL-1 phosphate. A total of 29% of the microorganisms were able to grow in nitrogen-free media and 24% were ammonia producers. Isolates ABC31, ANC48 and ANU49 were able to inhibit Fusarium moniliforme growth. All actinobacteria identified in this study belonged to the Streptomyces genus and presented potential as plant growth promoting agents.
Environmental Geochemistry and Health
Environmental degradation has increased, mainly as a result of anthropogenic effects arising from... more Environmental degradation has increased, mainly as a result of anthropogenic effects arising from population, industrial and agricultural growth. Water pollution is a problem that affects health, safety and welfare of the whole biota which shares the same environment. In Goiânia and metropolitan region, the main water body is the Meia Ponte River that is used for the abstraction of water, disposal of treated wastewater and effluents. In addition, this river receives wastewater from urban and rural areas. The aim in this present study was to evaluate the quality of raw water by some physical, chemical and toxicological tests. The physicochemical results found high levels of turbidity, conductivity, aluminum, phosphorus and metal iron, manganese, copper and lithium when compared to the standards of the Brazilian legislation. The values found of toxicity demonstrated a high degree of cytotoxicity and genotoxicity. Therefore, it was concluded that the Meia Ponte River has been undergoing constant environmental degradation, causing the poor quality of its waters. Thus, measures for the prevention and recovery should be adopted for the maintenance of the Meia Ponte River.
Anais da Academia Brasileira de Ciências
Anais da Academia Brasileira de Ciencias
In the present work, different Brazilian biomes aiming to identify and select cyclodextrin glycos... more In the present work, different Brazilian biomes aiming to identify and select cyclodextrin glycosyltransferase-producer bacteria are explored. This enzyme is responsible for converting starch to cyclodextrin, which are interesting molecules to carry other substances of economic interest applied by textile, pharmaceutical, food, and other industries. Based on the enzymatic index, 12 bacteria were selected and evaluated, considering their capacity to produce the enzyme in culture media containing different starch sources. It was observed that the highest yields were presented by the bacteria when grown in cornstarch. These bacteria were also characterized by sequencing of the 16S rRNA region and were classified as Bacillus, Paenibacillus, Gracilibacillus and Solibacillus.
Agrarian Academy
RESUMO Os vegetais terrestres são colonizados por um amplo número de micro-organismos. Micro-orga... more RESUMO Os vegetais terrestres são colonizados por um amplo número de micro-organismos. Micro-organismos rizosférios, que ao colonizarem as adjacências das raízes, disponibilizam uma extensa quantidade de nutrientes através da decomposição da matéria orgânica e da ciclagem de nutrientes, além de melhorar a arquitetura radicular e protegerem o hospedeiro contra fitopatógenos. O objetivo deste trabalho foi triar bactérias isoladas de rizosfera de alface (Lactuca sativa), com a melhor capacidade de promover crescimento vegetal. Seis cepas isoladas da rizosfera de alface, pertencentes a bacterioteca do LAMAB/UFG foram triadas quanto a sua capacidade de produção de ácido idol-acético (AIA), solubilização de fosfato, fixação de nitrogênio, produção de enzimas, celulases e quitinases, formação de biofilme e por fim, teste de colonização radicular. Todos os isolados apresentaram pelo menos uma característica analisada, assim como todos foram capazes de produzir biofilme. O isolado AG4 obteve o maior índice de solubilização de fosfato, o isolado AG7 foi o que produziu o maior número de fatores de crescimento vegetal. Com exceção de AG1, todos os outros foram capazes de colonizar as raízes de alface. Dessa forma, os isolados Enterobacter cloacae (AG3), Enterobacter cancerogenus (AG5), Enterobacter ludwigii (AG7) são bons candidatos a inoculantes, pois além da capacidade em colonizar as raízes ainda são produtores de um grande número de fatores do crescimento vegetal.
Enciclopédia Biosfera, 2016
Contaminants present in the cultures of plant tissue commonly are associated with endophytic micr... more Contaminants present in the cultures of plant tissue commonly are associated with endophytic microorganisms. These microorganisms usually have a production of some biological compounds which can be used as biotechnological products, among them, the exopolysaccharides (EPSs). A vast number of bacteria known produces significant amount of EPSs, drawing attention in recent decades both in the research and industry, due to its properties and applications. The production of EPSs by microorganisms is an alternative to a new source of production of soluble or insoluble polymers, that have a wide application in environmental areas and medicine, food chemical and pharmaceutical industries. EPSs are products of cellular metabolism of microorganisms that can be connected to the cell surface or when they are excreted to the medium. For this reason, the goal of this work was to verify the production of EPSs by gram-positive rods bacteria. Six strains were used for the production of EPSs in culture medium directed to the formation of the polymer cellulose. All of the used strains have produced significant amount of EPSs, having its higher production during the first 48 hours, being selected two strains with higher yields of EPSs. A positive association of bacterial density was linked to the production of biomass of EPSs. With the scanning electron microscopy (SEM) was able to see the production of EPSs. In conclusion, the results demonstrate the potential of bacterial strains to produce EPSs, being necessary new studies related to their characterization and potential application.
Pesquisa Agropecuária Tropical, 2016
Microorganisms play a vital role in maintaining soil fertility and plant health. They can act as ... more Microorganisms play a vital role in maintaining soil fertility and plant health. They can act as biofertilizers and increase the resistance to biotic and abiotic stress. This study aimed at isolating and characterizing plant growth-promoting bacteria associated with sugarcane, as well as assessing their ability to promote plant growth. Endophytic bacteria from leaf, stem, root and rhizosphere were isolated from the RB 867515 commercial sugarcane variety and screened for indole acetic acid (IAA) production, ability to solubilize phosphate, fix nitrogen and produce hydrogen cyanide (HCN), ammonia and the enzymes pectinase, cellulase and chitinase. A total of 136 bacteria were isolated, with 83 of them presenting some plant growth mechanism: 47 % phosphate solubilizers, 26 % nitrogen fixers and 57 % producing IAA, 0.7 % HCN and chitinase, 45 % ammonia, 30 % cellulose and 8 % pectinase. The seven best isolates were tested for their ability to promote plant growth in maize. The isolates ...
Enciclopédia Biosfera, 2016
Bacteriocins are antibiotics classified as natural products, in other words, secondary metabolite... more Bacteriocins are antibiotics classified as natural products, in other words, secondary metabolites produced by bacteria. Endophytic, microorganisms that have plants as hosts in at least one life stage, are a good example of bacteriocin producers. The aim of this work was to evaluate the antimicrobial activity probably due to bacteriocin production by endophytic bacteria isolated from Jacarranda decurrens Cham. against different indicator strains and the bioactive metabolites sensibility to temperature (75-80ºC) and to trypsin in two different media. It was used 10 endophytic bacterial isolates previously isolated from Jacaranda decurrens Cham. 70% of the isolated presented antimicrobial activity, evidenced by inhibition halos in agar plates against at least one of the 15 indicators strains. The antimicrobial compounds generated by the isolates CAR 4, CAR 5 and CAR 7 were thermolabile and resistant to trypsin. The metabolites produced by CAR 6 were sensible to the heat and the enzymatic treatment and the isolates CAR 2, CAR 4, CAR 5 and CAR 7 also produced substances sensible to these conditions. The production of the antimicrobial compounds just happened in media 523 and it was not observed the presence of bacteriophages. Substances with bacteriocinogenic activity and with broad spectrum of action against pathogenic organisms was produced by the endophytic bacteria from the medicinal plant, thus exhibiting interesting potential to be applied as antimicrobials and in biological control.
Enciclopédia Biosfera, 2016
Endophytic bacteria exhibit a wide biotechnological potential, not limited to the plant growth pr... more Endophytic bacteria exhibit a wide biotechnological potential, not limited to the plant growth promotion, and often also described by their bioremediation capacity. These microorganisms participate from the hydrocarbon degradation and other organic pollutants, to heavy metals remediation, elevating significantly the efficiency of phitoremediation systems. The aim of this study was to evaluate qualitatively the hydrocarbon degradation capacity and phenol tolerance by endophytic bacteria from bamboo. For the hydrocarbon degradation screening, it was performed tests in microplates with the microbial cultivation using each one of the following compounds as a sole carbon source: diesel oil, gasoline, kerosene, burned oil, lubricants (20W40, 20W50, 5W50 and 15W40). For phenol tolerance analysis, the endophytic were cultivated in mineral minimum solid medium, using phenol as the sole carbon source in three concentrations: 50, 100 and 150 mg/L. For the 21 evaluated bacterial isolates, one isolate (7F) presented the fuel degradation capacity (diesel oil, gasoline and kerosene), and two isolates (9F and 6F) exhibited partial degradation capacity. The vegetal oil degradation was observed for three isolates (6F, 7F and 9F) and partially for the isolate 10F. The degradation for the tested lubricants was observed partially for one isolate (7F), with the partial degradation for 5W50 and 15W40 oils by the 8F isolate. Fifteen isolates were tolerant to phenol in all the analyzed concentrations. The results suggest a potential application of the endophytic bacterial isolates in bioremediation process.
Revista do Instituto de Medicina Tropical de São Paulo, 2015
The evaluation of workers as potential reservoirs and disseminators of pathogenic bacteria has be... more The evaluation of workers as potential reservoirs and disseminators of pathogenic bacteria has been described as a strategy for the prevention and control of healthcare-associated infections (HAIs). The aim of this study was to evaluate the presence of Enterobacteriaceae in the oral cavity of workers at an oncology hospital in the Midwest region of Brazil, as well as to characterize the phenotypic profile of the isolates. Saliva samples of 294 workers from the hospital’s healthcare and support teams were collected. Microbiological procedures were performed according to standard techniques. Among the participants, 55 (18.7%) were colonized by Enterobacteriaceae in the oral cavity. A total of 64 bacteria were isolated, including potentially pathogenic species. The most prevalent species was Enterobacter gergoviae (17.2%). The highest rates of resistance were observed for β-lactams, and 48.4% of the isolates were considered multiresistant. Regarding the enterobacteria isolated, the pro...
Algal Research, 2015
ABSTRACT Due to the currently abundant supply of marine microalgae, which can be found in seawate... more ABSTRACT Due to the currently abundant supply of marine microalgae, which can be found in seawater, as well as microalgae's ability to uptake different chemicals, it appears as a promising raw material with potential for many commercial uses. Despite having a high amount of metal in their biomass, the lipids within marine microalgae can be converted into biodiesel. Analyses of 26 chemical elements (Al, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sn, Sr, Ti, Tl, V, and Zn) were performed by ICP-OES with the goal of quantifying the inorganic content of marine microalgae's biomass. Regardless of the cultivation media used, microalgae presented differences in their chemical element profile. Strains showed a 12.9% to 36.3% mass of analyzed elements per dry biomass, which represent a relatively high percentage for a feedstock used in biofuels. Among the 36 assayed microalgae, Biddulphia sp., Planktolyngbya limnetica, Amphora sp. (1), Navicula sp. (3) and Synechococcus sp. are most indicated for this purpose as they contain a lower concentration of chemical elements when compared to other samples. However, their profile warns that water quality control is needed for toxic metals such as Ba, Cd, and Pb.
Revista da Sociedade Brasileira de Medicina Tropical, 2011
INTRODUÇÃO: O aumento da prevalência de isolados de enterococos em hospitais, particularmente Ent... more INTRODUÇÃO: O aumento da prevalência de isolados de enterococos em hospitais, particularmente Enterococcus resistente à vancomicina (VRE), é importante por causa da limitada terapia antimicrobiana efetiva para o tratamento de infecções enterocócicas. MÉTODOS: O presente trabalho apresentou uma investigação retrospectiva de dados de suscetibilidade in vitro quantitativa para uma variedade de antimicrobianos frente aos isolados de Enterococcus spp. e avaliação da associação de resistência entre os agentes antimicrobianos apontados como escolha para o tratamento de infecções causadas por VRE, através do cálculo do risco relativo. RESULTADOS: Dos 156 isolados de enterococos, 40 (25,6%) foram resistentes a três ou mais antimicrobianos, incluindo 7,7% (n = 12/156) resistentes à vancomicina. A associação de resistência elevada foi mais pronunciada entre os isolados de VREs com antimicrobianos alternativos e primários para o tratamento de infecções causadas por estes patógenos, incluindo am...
Revista de Patologia Tropical, 2009
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Papers by José Daniel Vieira