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Efeito da inoculação de uma bactéria endofítica fixadora de nitrogênio (Acinetobacter sp. ICB117) no desenvolvimento da cana-de-açucar (Saccharum sp. variedade SP791011).; Effect of a nitrogen-fixing endophytic bacterium (Acinetobacter sp.) in sugarcane (Saccharum sp.) growth.

Kleingesinds, Carolina Krebs
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/12/2010 PT
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O presente estudo teve por objetivo analisar os efeitos da inoculação de Acinetobacter sp. ICB117 no desenvolvimento da cana-de-açúcar variedade SP791011. As plantas foram cultivadas a partir de toletes com uma gema e fornecidas pelo Centro de Tecnologia Canavieira. Aos 30 dias de idade, foram submetidas aos seguintes tratamentos: controle (C) sem inoculação e solução de Hoagland sem nitrogênio; nitrato (N) sem inoculação e solução de Hoagland com nitrato (15 mM); bactéria (B) inoculação bacteriana e solução de Hoagland sem nitrogênio; bactéria + nitrato (BN) inoculação bacteriana e solução de Hoagland com nitrato (15 mM). Antes da realização da inoculação, foi inserido em ICB117 um plasmídio que contém um gene de expressão para o GFP. O material vegetal foi coletado mensalmente (2 coletas), sendo os seguintes parâmetros analisados: altura, nº de folhas, massa seca, composição de aminoácidos na seiva xilemática, razão C/N das raízes e folhas, atividade da nitrato redutase foliar, assimilação máxima de CO2 e estimativa da população endofítica de ICB117.; Acinetobacter sp. ICB117 is a nitrogen-fixing bacterium isolated from Brazilian sugarcane (Saccharum sp. variety SP791011) which releases amino acids...

Characterization of bornite (Cu5FeS4) electrodes in the presence of the bacterium Acidithiobacillus ferrooxidans

Bevilaqua, Denise; Diéz-Perez, Ismael; Fugivara, Cecílio S.; Sanz, Fausto; Garcia Jr., Oswaldo; Benedetti, Assis V.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 637-644
ENG
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Bornite electrodes were characterized in the absence or in the presence of Acidithiobacillus ferrooxidans, which is an important microorganism involved in metal bioleaching processes. The presence of the bacterium modified the mineral/electrolyte interface, increasing the corrosion rate, as revealed by interferometric, AEM, ICP and EIS analyses. As a consequence of bacterial activity the electrode became porous, increasing its surface heterogeneity. This behavior was correlated with the evolution of impedance diagrams obtained during the time course of experiments. The main difference in these diagrams was the presence of an inductive feature (up to 44 h), which was related to bacterial action on the mineral dissolution, better than to its adhesion on the bornite. The total real impedance measured in presence of the bacterium was about 10 times lower than in its absence, due to the acceleration of the mineral dissolution, because an oxidant environment was maintained.

Genome analysis of Desulfotomaculum gibsoniae strain GrollT a highly versatile Gram-positive sulfate-reducing bacterium

Kuever, Jan; Visser, Michael; Loeffler, Claudia; Boll, Mathias; Worm, Petra; Sousa, D. Z.; Plugge, Caroline M.; Schaap, Peter J.; Muyzer, Gerard; Pereira, Inês A. C.; Pashina, Sofiya N.; Goodwin, Lynne A.; Kyrpides, Nikos C.; Detter, Janine; Woyke, Tanja
Fonte: Genomic Standards Consortium Publicador: Genomic Standards Consortium
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
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Desulfotomaculum gibsoniae is a mesophilic member of the polyphyletic spore-forming genus Desulfotomaculum within the family Peptococcaceae. This bacterium was isolated from a freshwater ditch and is of interest because it can grow with a large variety of organic substrates, in particular several aromatic compounds, short-chain and medium-chain fatty acids, which are degraded completely to carbon dioxide coupled to the reduction of sulfate. It can grow autotrophically with H2 + CO2 and sulfate and slowly acetogenically with H2 + CO2, formate or methoxylated aromatic compounds in the absence of sulfate. For growth it does not require any vitamins. Here, we describe the features of D. gibsoniae strain GrollT together with the genome sequence and annotation. The chromosome has 4,855,529 bp organized in one circular contig and is the largest genome of all sequenced Desulfotomaculum spp., so far. A total of 4666 candidate protein-encoding genes and 96 RNA genes were identified. Genes of the acetyl-CoA pathway possibly involved in heterotrophic growth, and in CO2 fixation during autotrophic growth are present. The genome contains a large set of genes for the anaerobic transformation and degradation of aromatic compounds, which are lacking in the other sequenced Desulfotomaculum genomes.

Endophytic colonization of rice (Oryza sativa L.) by the diazotrophic bacterium Burkholderia kururiensis and its ability to enhance plant growth

Mattos,Katherine A.; Pádua,Vania L.M.; Romeiro,Alexandre; Hallack,Leticia F.; Neves,Bianca C.; Ulisses,Tecia M.U.; Barros,Claudia F.; Todeschini,Adriane R.; Previato,José O.; Mendonça-Previato,Lucia
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2008 EN
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Burkholderia kururiensis is a diazotrophic bacterium originally isolated from a polluted aquifer environment and presents a high level of similarity with the rice endophyte "B. brasilensis" species. This work assessed the ability of B. kururiensis to endophytically colonize rice plantlets by monitoring different tissues of root-inoculated plants for the presence of bacterial growth in different media, electron microscopy and by 16S rDNA analysis. Observations of roots, stems and leaves of inoculated rice plantlets by electron microscopy revealed B. kururiensis colonization predominantly on root hair zones, demonstrating endophytic colonization primarily through the endodermis, followed by spreading into xylem vessels, a possible pathway leading to aerial parts. Although indifferent for the bacterial growth itself, addition of a nitrogen source was a limiting factor for endophytic colonization. As endophytic colonization was directly associated to an enhanced plant development, production of phytohormone auxin/indole-3-acetic acid by B. kururiensis was assayed with transgenic rice plantlets containing an auxin-responsive reporter (DR5-GUS). Our findings suggest the ability of auxin production by plant-associated B. kururiensis which may have a stimulatory effect on plant development...

Removal of corper(II) Ions from aqueous solution by a lactic acid bacterium

Yilmaz,M.; Tay,T.; Kivanc,M.; Turk,H.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2010 EN
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Enterococcus faecium, a lactic acid bacterium (LAB), was evaluated for its ability to remove copper(II) ions from water. The effects of the pH, contact time, initial concentration of copper(II) ions, and temperature on the biosorption rate and capacity were studied. The initial concentrations of copper(II) ions used to determine the maximum amount of biosorbed copper(II) ions onto lyophilised lactic acid bacterium varied from 25 mg L-1 to 500 mg L-1. Maximum biosorption capacities were attained at pH 5.0 and 6.0. Temperature variation between 20°C and 40°C did not affect the biosorption capacity of the bacterial biomass. The highest copper(II) ion removal capacity was 106.4 mg per g dry biomass. The correlation regression coefficients show that the biosorption process can be well defined by the Freundlich equation. The change in biosorption capacity with time was found to fit a pseudo-second-order equation.

Extracellular proteases of Halobacillus blutaparonensis strain M9, a new moderately halophilic bacterium

Santos,Anderson F.; Valle,Roberta S.; Pacheco,Clarissa A.; Alvarez,Vanessa M.; Seldin,Lucy; Santos,André L.S.
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 EN
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Halophilic microorganisms are source of potential hydrolytic enzymes to be used in industrial and/or biotechnological processes. In the present study, we have investigated the ability of the moderately halophilic bacterium Halobacillus blutaparonensis (strain M9), a novel species described by our group, to release proteolytic enzymes. This bacterial strain abundantly proliferated in Luria-Bertani broth supplemented with 2.5% NaCl as well as secreted proteases to the extracellular environment. The production of proteases occurred in bacterial cells grown under different concentration of salt, ranging from 0.5% to 10% NaCl, in a similar way. The proteases secreted by H. blutaparonensis presented the following properties: (i) molecular masses ranging from 30 to 80 kDa, (ii) better hydrolytic activities under neutral-alkaline pH range, (iii) expression modulated according to the culture age, (iv) susceptibility to phenylmethylsulphonyl fluoride, classifying them as serine-type proteases, (v) specific cleavage over the chymotrypsin substrate, and (vi) enzymatic stability in the presence of salt (up to 20% NaCl) and organic solvents (e.g., ether, isooctane and cyclohexane). The proteases described herein are promising for industrial practices due to its haloalkaline properties.

Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) and its relationship with the citrus canker bacterium Xanthomonas axonopodis pv citri in Brazil

Chagas,Marcone C.M.; Parra,José R.P.; Namekata,Takao; Hartung,John S.; Yamamoto,Pedro T.
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2001 EN
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The relationship of the citrus canker bacterium Xanthomonas axonopodis pv citri with the citrus leafminer (CLM), Phyllocnistis citrella Stainton was investigated. The experiment was conducted under laboratory conditions at 28±2ºC, 70±10% RH and 14h photophase and in a greenhouse. Sweet orange (Citrus sinensis L. Osbeck) "Caipira"cv was used to rear CLM. Plants inoculated with 2nd and 3rd instar larvae or pupae showed high percentages (94.3, 98.3 and 100%, respectively) of bacterium-infected leaves. The damage caused by this insect was responsible for the increase in citrus canker infestation. The leaf infection rate by X. axonopodis pv citri on pre-injured leaves was similar to that observed on mechanically damaged leaves inoculated with the bacterium, with 94.1% to 97.0% of the leaves presenting bacterial pustules. The bacterium can also penetrate through the stomata. An 11-fold lower infection rate was observed as compared to the leaves injured by the insect seven days after inoculation. Under such conditions the percentage of cankered leaves increased to 41.2% at 14 days, a value corresponding to about 50% of the leaves attacked by the insect. In this paper it is also pointed out the significance of the damages caused by CLM in terms of the increase of citrus canker...

Laribacter hongkongensis gen. nov., sp. nov., a Novel Gram-Negative Bacterium Isolated from a Cirrhotic Patient with Bacteremia and Empyema

Yuen, Kwok-Yung; Woo, Patrick C. Y.; Teng, Jade L. L.; Leung, Kit-Wah; Wong, Michelle K. M.; Lau, Susanna K. P.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /12/2001 EN
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A bacterium was isolated from the blood and empyema of a cirrhotic patient. The cells were facultatively anaerobic, nonsporulating, gram-negative, seagull shaped or spiral rods. The bacterium grows on sheep blood agar as nonhemolytic, gray colonies 1 mm in diameter after 24 h of incubation at 37°C in ambient air. Growth also occurs on MacConkey agar and at 25 and 42°C but not at 4, 44, and 50°C. The bacterium can grow in 1 or 2% but not 3, 4, or 5% NaCl. No enhancement of growth is observed with 5% CO2. The organism is aflagellated and nonmotile at both 25 and 37°C. It is oxidase, catalase, urease, and arginine dihydrolase positive, and it reduces nitrate. It does not ferment, oxidize, or assimilate any sugar tested. 16S rRNA gene sequencing showed that there are 91 base differences (6.2%), 112 base differences (7.7%), and 116 base differences (8.2%) between the bacterium and Microvirgula aerodenitrificans, Vogesella indigofera, and Chromobacterium species, respectively. The G+C content (mean and standard deviation) is 68.0% ± 2.43%, and the genomic size is about 3 Mb. Based on phylogenetic affiliation, the bacterium belongs to the Neisseriaceae family of the β-subclass of Proteobacteria. For these reasons, a new genus and species...

Pathogenicity of Moraxella osloensis, a Bacterium Associated with the Nematode Phasmarhabditis hermaphrodita, to the Slug Deroceras reticulatum

Tan, Li; Grewal, Parwinder S.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/2001 EN
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Moraxella osloensis, a gram-negative bacterium, is associated with Phasmarhabditis hermaphrodita, a nematode parasite of slugs. This bacterium-feeding nematode has potential for the biological control of slugs, especially the grey garden slug, Deroceras reticulatum. Infective juveniles of P. hermaphrodita invade the shell cavity of the slug, develop into self-fertilizing hermaphrodites, and produce progeny, resulting in host death. However, the role of the associated bacterium in the pathogenicity of the nematode to the slug is unknown. We discovered that M. osloensis alone is pathogenic to D. reticulatum after injection into the shell cavity or hemocoel of the slug. The bacteria from 60-h cultures were more pathogenic than the bacteria from 40-h cultures, as indicated by the higher and more rapid mortality of the slugs injected with the former. Coinjection of penicillin and streptomycin with the 60-h bacterial culture reduced its pathogenicity to the slug. Further work suggested that the reduction and loss of pathogenicity of the aged infective juveniles of P. hermaphrodita to D. reticulatum result from the loss of M. osloensis from the aged nematodes. Also, axenic J1/J2 nematodes were nonpathogenic after injection into the shell cavity. Therefore...

Environmental Occurrence of the Whipple’s Disease Bacterium (Tropheryma whippelii)

Maiwald, Matthias; Schuhmacher, Frank; Ditton, Hans-Jürgen; von Herbay, Axel
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /02/1998 EN
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Whipple’s disease is a systemic disorder in which a gram-positive rod-shaped bacterium is constantly present in infected tissues. After numerous unsuccessful attempts to culture this bacterium, it was eventually characterized by 16S rRNA gene analysis to be a member of the actinomycetes. The name Tropheryma whippelii was proposed. Until now, the bacterium has only been found in infected human tissues, but there is no evidence for human-to-human transmission. Here we report the detection of DNA specific for the Whipple’s disease bacterium in 25 of 38 wastewater samples from five different sewage treatment plants in the area of Heidelberg, Germany. These findings provide the first evidence that T. whippelii occurs in the environment, within a polymicrobial community. This is in accordance with the phylogenetic relationship of this bacterium as well as with known epidemiological aspects of Whipple’s disease. Our data argue for an environmental source for infection with the Whipple’s disease bacterium.

A Plant Growth-Promoting Bacterium That Decreases Nickel Toxicity in Seedlings

Burd, Genrich I.; Dixon, D. George; Glick, Bernard R.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/1998 EN
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A plant growth-promoting bacterium, Kluyvera ascorbata SUD165, that contained high levels of heavy metals was isolated from soil collected near Sudbury, Ontario, Canada. The bacterium was resistant to the toxic effects of Ni2+, Pb2+, Zn2+, and CrO4−, produced a siderophore(s), and displayed 1-aminocyclopropane-1-carboxylic acid deaminase activity. Canola seeds inoculated with this bacterium and then grown under gnotobiotic conditions in the presence of high concentrations of nickel chloride were partially protected against nickel toxicity. In addition, protection by the bacterium against nickel toxicity was evident in pot experiments with canola and tomato seeds. The presence of K. ascorbata SUD165 had no measurable influence on the amount of nickel accumulated per milligram (dry weight) of either roots or shoots of canola plants. Therefore, the bacterial plant growth-promoting effect in the presence of nickel was probably not attributable to the reduction of nickel uptake by seedlings. Rather, it may reflect the ability of the bacterium to lower the level of stress ethylene induced by the nickel.

Capsule-Transmitted Gut Symbiotic Bacterium of the Japanese Common Plataspid Stinkbug, Megacopta punctatissima

Fukatsu, Takema; Hosokawa, Takahiro
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /01/2002 EN
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The Japanese common plataspid stinkbug, Megacopta punctatissima, deposits small brown particles, or symbiont capsules, on the underside of the egg mass for the purpose of transmission of symbiotic bacteria to the offspring. We investigated the microbiological aspects of the bacteria contained in the capsule, such as microbial diversity, phylogenetic placement, localization in vivo, and fitness effects on the host insect. Restriction fragment length polymorphism analysis of 16S ribosomal DNA clones revealed that a single bacterial species dominates the microbiota in the capsule. The bacterium was not detected in the eggs but in the capsules, which unequivocally demonstrated that the bacterium is transmitted to the offspring of the insect orally rather than transovarially, through probing of the capsule content. Molecular phylogenetic analysis showed that the bacterium belongs to the γ-subdivision of the Proteobacteria. In adult insects the bacterium was localized in the posterior section of the midgut. Deprivation of the bacterium from the nymphs resulted in retarded development, arrested growth, abnormal body coloration, and other symptoms, suggesting that the bacterium is essential for normal development and growth of the host insect.

Anaerobic Respiration Using Fe3+, S0, and H2 in the Chemolithoautotrophic Bacterium Acidithiobacillus ferrooxidans

Ohmura, Naoya; Sasaki, Kazuhiro; Matsumoto, Norio; Saiki, Hiroshi
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/2002 EN
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The chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans has been known as an aerobe that respires on iron and sulfur. Here we show that the bacterium could chemolithoautotrophically grow not only on H2/O2 under aerobic conditions but also on H2/Fe3+, H2/S0, or S0/Fe3+ under anaerobic conditions. Anaerobic respiration using Fe3+ or S0 as an electron acceptor and H2 or S0 as an electron donor serves as a primary energy source of the bacterium. Anaerobic respiration based on reduction of Fe3+ induced the bacterium to synthesize significant amounts of a c-type cytochrome that was purified as an acid-stable and soluble 28-kDa monomer. The purified cytochrome in the oxidized form was reduced in the presence of the crude extract, and the reduced cytochrome was reoxidized by Fe3+. Respiration based on reduction of Fe3+ coupled to oxidation of a c-type cytochrome may be involved in the primary mechanism of energy production in the bacterium on anaerobic iron respiration.

Molecular Characterization of the Nonphotosynthetic Partner Bacterium in the Consortium “Chlorochromatium aggregatum”

Kanzler, Birgit E. M.; Pfannes, Kristina R.; Vogl, Kajetan; Overmann, Jörg
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/2005 EN
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Phototrophic consortia represent valuable model systems for the study of signal transduction and coevolution between different bacteria. The phototrophic consortium “Chlorochromatium aggregatum” consists of a colorless central rod-shaped bacterium surrounded by about 20 green-pigmented epibionts. Although the epibiont was identified as a member of the green sulfur bacteria, and recently isolated and characterized in pure culture, the central colorless bacterium has been identified as a member of the β-Proteobacteria but so far could not be characterized further. In the present study, “C. aggregatum” was enriched chemotactically, and the 16S rRNA gene sequence of the central bacterium was elucidated. Based on the sequence information, fluorescence in situ hybridization probes targeting four different regions of the 16S rRNA were designed and shown to hybridize exclusively to cells of the central bacterium. Phylogenetic analyses of the 1,437-bp-long sequence revealed that the central bacterium of “C. aggregatum” represents a so far isolated phylogenetic lineage related to Rhodoferax spp., Polaromonas vacuolata, and Variovorax paradoxus within the family Comamonadaceae. The majority of relatives of this lineage are not yet cultured and were found in low-temperature aquatic environments or aquatic environments containing xenobiotica or hydrocarbons. In CsCl-bisbenzimidazole equilibrium density gradients...

EXPERIMENTAL STUDIES OF THE NASOPHARYNGEAL SECRETIONS FROM INFLUENZA PATIENTS : X. THE IMMUNIZING EFFECTS IN RABBITS OF SUBCUTANEOUS INJECTIONS OF KILLED CULTURES OF BACTERIUM PNEUMOSINTES.

Olitsky, Peter K.; Gates, Frederick L.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 30/11/1922 EN
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A series of rabbits was subcutaneously injected with three measured doses of killed cultures of two strains of Bacterium pneumosintes derived from the nasopharyngeal secretions of influenza patients. These rabbits were subsequently tested for the development of serum antibodies and for the presence of an induced immunity to the living organisms, with the following results. The serum of eleven of fifteen rabbits, tested from 10 to 27 days after the final subcutaneous injection, specifically agglutinated Bacterium pneumosintes, whereas normal rabbit serum did not. Nineteen vaccinated rabbits were subjected to protection experiments. Two of them were unaffected by an intratracheal injection of Bacterium pneumosintes, contained in the lung tissues of previously infected animals, in a dose which typically affected the control rabbits. Fifteen of the other seventeen proved to be completely resistant when tested by intratracheal injections of Bacterium pneumosintes cultures that produced typical infections in the controls. Ten of these fifteen rabbits were injected intravenously with living cultures of pneumococcus, Streptococcus hamolyticus, or Bacillus pfeifferi in doses which were non-infective under normal conditions, but infective, as experience has shown...

Endohyphal Bacterium Enhances Production of Indole-3-Acetic Acid by a Foliar Fungal Endophyte

Hoffman, Michele T.; Gunatilaka, Malkanthi K.; Wijeratne, Kithsiri; Gunatilaka, Leslie; Arnold, A. Elizabeth
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 24/09/2013 EN
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Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production...

European foul brood : a disease of the larval honeybee (Apis mellifera L.) caused by a combination of streptococcus pluton (Bacillus pluton White) and Bacterium eurydice White

Bailey, L.
Fonte: INRA - Instituto Nacional de Investigação Agronômica da França Publicador: INRA - Instituto Nacional de Investigação Agronômica da França
Tipo: Journal Article-postprint
EN; ENGLISH
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Result of preliminary experiments have shown that European foul brood disease of the larval honeybee can be caused in bee colonies by spraying their brood with suspensions of Streptococcus pluton (Bacillus pluton White) and Bacterium eurydice White if the two organisms are grown together in mixed anaerobic culture ; fifth subcultures of a mixed culture were usually virulent, although virulence diminished rapidly after further sub-cultivation. It was not possible to cause the disease by simultaneous inoculation with separate cultures of the two organisms. As there is a tendency for colonies of S. pluton and B. eurydice to grow within, or upon, each other on agar in anaerobic cultures, the separate cultures of each organism were subcultured five times to try to ensure the exclusion of the other. The results of these experiments showed that virulence was maintained by one or both organisms in mixed culture, but the possibility remained that only one of the organisms was pathogenic; its virulence may have been maintained by the growth of the other which may, in vivo, be a secondary invader of the diseased larva ...

The isolation and cultural characteristics of streptococcus pluton and further observations on bacterium eurydice

Bailey, L.
Fonte: INRA - Instituto Nacional de Investigação Agronômica da França Publicador: INRA - Instituto Nacional de Investigação Agronômica da França
Tipo: Journal Article-postprint
EN; ENGLISH
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36.46%
An account is given of the development of a reliable method for the isolation of Streptococcus pluton (Bacillus pluton White), an organism associated with European foul-brood disease of the larval honeybee. S. pluton, isolated as an anaerobe, may be trained to grow as an aerobe in rod form. Its principal anaerobic growth requirements are a low molar ratio of Na: K, high inorganic phosphate concentration, glucose or fructose, and undetermined factors provided by yeast extract. Peptones are harmful to growth. Aerobic growth has no very critical requirements other than glucose, fructose or sucrose. Bacterium eurydice White which, together with S. pluton, causes European foul-brood disease grows well anaerobically on a yeast extract + glucose + fructose medium; either sugar alone supports only feeble anaerobic growth. Anaerobic growth of B.eurydice is also accelerated by a low molar ratio of Na: K and is inhibited by peptones. S. pluton and B.eurydice appear to be separate organisms; no evidence has been obtained to support claims by previous workers that S. pluton is a variant of B. eurydice.

Bactéria termófila Thermus filiformis : produção de carotenóides e avaliação da capacidade antioxidante; Thermophilic bacterium Thermus filiformis : production of carotenoids and evaluation of antioxidant capacity

Fernanda Mandelli
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/08/2010 PT
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Os carotenoides pertencem a um grupo de pigmentos naturais amplamente distribuídos na natureza, com grande diversidade de estruturas e funções. O interesse pelos carotenoides tem aumentado consideravelmente nos últimos anos pela evidência dos seus já conhecidos benefícios à saúde humana, devido às suas propriedades antioxidantes, anticarcinogênicas e imunomodulatórias. As principais fontes industriais de carotenoides são a síntese química e a extração a partir de plantas. Porém, são poucos os carotenoides que possuem métodos economicamente eficientes de produção. Uma alternativa para a obtenção natural destes pigmentos é a sua produção por micro-organismos, sendo uma das fontes as bactérias termófilas que, em sua maioria, possuem carotenoides com estrutura específica para fortalecimento da membrana celular. Assim sendo, o presente estudo tem como objetivos: identificar os carotenoides da linhagem Thermus filiformis ATCC 43280, avaliar o crescimento de massa celular, produção de carotenóides e porcentagem de proteção contra o oxigênio singlete através de diferentes condições de cultivo e verificar a atividade antioxidante do extrato rico em carotenoides na desativação do radical ABTS¿+ (2,2¿- azinobis-(3-etilbenzotiazolina-6-ácido sulfônico)) e do peróxido de hidrogênio. Para atingir os objetivos...

Treatment of common warts with the immune stimulant Propionium bacterium parvum

Nasser,Nilton
Fonte: Sociedade Brasileira de Dermatologia Publicador: Sociedade Brasileira de Dermatologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2012 EN
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BACKGROUND: Warts are epithelial proliferations in the skin and mucous membrane caused by various types of HPV. They can decrease spontaneously or increase in size and number according to the patient's immune status. The Propionium bacterium parvum is a strong immune stimulant and immune modulator and has important effects in the immune system and it is able to produce antibodies in the skin. OBJECTIVE: To show the efficacy of the Propionium bacterium parvum in saline solution in the treatment of skin warts. METHODS: A randomized double-blind study. Twenty patients with multiple warts were divided into two groups: one received 0,1ml intradermal injection of placebo solution in just one of the warts and the other received 0,1 ml of saline solution of Propionium bacterium parvum, one dose a month, for 3 to 5 months. RESULTS: Among the 20 patients who participated in the study, ten received the placebo and ten received the saline solution with Propionium bacterium parvum. In 9 patients treated with the Propionium bacterium parvum solution the warts disappeared without scars and in 1 patient it decreased in size. In 9 patients who received the placebo no change to the warts was observed and in 1 it decreased in size. CONCLUSIONS: The immune modulator and immune stimulant Propionium bacterium parvum produced antibodies in the skin which destroyed the warts without scars...