1. Rapid detection and molecular profiling of water-borne bacteria - Hoefel, Daniel
In this thesis, detection of active water-borne bacteria was achieved by combining flow cytometry with vital dyes that characterise the metabolic status of cells. Following optimisation, these techniques were applied to investigate the activity of bacteria exposed to disinfection, both in the laboratory and in real systems. Raw and potable waters from various locations around South Australia were then analysed to investigate relationships between numbers of active bacteria and those detected by traditional culture-based techniques. Flow cytometric cell sorting of active bacteria followed by 16S rRNA gene-directed PCR and denaturing gradient gel electrophoresis (DGGE) was then used to track the...

2. Bioluminescent bacteria: lux genes as environmental biosensors - Nunes-Halldorson,Vânia da Silva; Duran,Norma Letícia
Bioluminescent bacteria are widespread in natural environments. Over the years, many researchers have been studying the physiology, biochemistry and genetic control of bacterial bioluminescence. These discoveries have revolutionized the area of Environmental Microbiology through the use of luminescent genes as biosensors for environmental studies. This paper will review the chronology of scientific discoveries on bacterial bioluminescence and the current applications of bioluminescence in environmental studies, with special emphasis on the Microtox toxicity bioassay. Also, the general ecological significance of bioluminescence will be addressed.

3. Caracterização de bactérias mesófilas presentes em processo de compostagem - Symanski, Caroline Seitenfus
O estudo das populações microbianas presentes em uma leira de compostagem pode gerar valiosas informações que contribuam para o aprimoramento da técnica de compostagem. O presente trabalho teve como objetivo avaliar a eficiência da compostagem, como tratamento de resíduos, através da identificação da sucessão bacteriana (bactérias mesófilas aeróbias e anaeróbias facultativas) e da sobrevivência de bactérias potencialmente patogênicas ao longo do processo, além de avaliar a resistência destas populações a antimicrobianos e metais pesados. Amostras do material sendo compostado foram utilizadas para a quantificação de heterotróficos, determinação de coliformes totais e fecais e semeadura em diferentes meios de cultura para...

4. Propolis antimicrobial activity against periodontopathic bacteria - Gebara,Elaine C.E.; Lima,Luiz A.; Mayer,Marcia P.A.
Propolis extract antimicrobial activity against periodontopathic (ATCC) bacteria was investigated "in vitro". Bacterial strains tested were: Prevotella intermedia, Prevotella melaninogenica, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Capnocytophaga gingivalis and Fusobacterium nucleatum. Minimal inhibitory concentration (MIC) for the strains tested was determined using the method of broth dilution with the propolis extract in serial concentrations. Results showed MIC of 1 µg/ml for Actinobacillus actinomycetemcomitans and Capnocytophaga gingivalis; and 0.25 µg/ml for Prevotella intermedia, Prevotella melaninogenica, Porphyromonas gingivalis and Fusobacterium nucleatum. Some superinfectant organisms were also tested: Candida albicans susceptibility to propolis ethanolic extract was demonstrated at a concentration of 12 µg/ml. The MIC...

5. Biodegradabilidade de isômeros de xileno por bactérias isoladas determinal portuário de SUAPE-PE - Laureni Alves de Lima
Xylene, also known as dimethylbenzene is a monoaromatic hydrocarbon existing in three isometric forms: ortho, meta and para. It is widely used in paints, glues, printer ink, pesticides, in the leather and rubber industries, in histology labs and is a component of gasoline. The constant use of this compound may cause damage in the environment and to human health, owing to its toxicity. An alternative way of eliminating or minimizing these problems, is bioremediation, a technique that uses microorganisms to degrade pollutants. This study aims to investigate the biodegradability of xylene isomers by bacteria isolated from the Port Terminal at...

6. Efeitos da monensina sobre a fermentação e sensibilidade de bactérias ruminais de bovinos sob dietas ricas em volumoso ou concentrado - Lana,Rogério de Paula; Russell,James B.
Objetivou-se avaliar os efeitos da monensina sobre as mudanças nos padrões de fermentação e resistência à perda do potássio intracelular das bactérias ruminais provenientes de quatro bovinos recebendo dietas ricas em volumoso ou concentrado. As bactérias obtidas por centrifugação diferencial foram resuspensas em um meio pobre em potássio, no qual foi medida a perda do potássio intracelular, em 10 minutos de incubação, pelo uso de nível crescente de monensina. Os produtos de fermentação foram obtidos após 24 horas de incubação da cultura com feno de gramínea (100 mg/10 mL). As bactérias obtidas de animais recebendo dieta com 90% de concentrado...

7. Qualidade microbiológica de leite UHT caprino: pesquisa de bactérias dos gêneros Staphylococcus, Bacillus e Clostridium - Vittori, Juliano; Schoken-Iturrino, Ruben Pablo; Poiatti, Maria Luiza; Pigatto, Caroline Peters; Chioda, Tammy Priscila; Ribeiro, César Augusto Martins; Garcia, Gisela Rojas; Ragazani, Adriana Valim Ferreira
Com o objetivo de avaliar a qualidade microbiológica do leite UHT caprino, 100 amostras provenientes das regiões Sul e Sudeste do país foram analisadas através do isolamento e da identificação de bactérias do gênero Staphylococcus sp., Bacillus sp. e Clostridium sp.. Com exceção do Clostridium sp., todos os gêneros estudados foram isolados. A presença de bactérias mesofílicas foi positiva em 21% das amostras. Bacillus sp. e Staphylococcus sp. foram isoladas em 32% e 36% das amostras analisadas respectivamente. As contagens de Staphylococcus sp. foram em média de 5,21x101UFC mL-1, enquanto que para Bacillus sp. foi de 4,87x101UFC mL-1. Os resultados...

8. Spatial Variation of Bacteria in Surface Waters of Paranaguá and Antonina Bays, Paraná, Brazil - Kolm,Hedda Elisabeth; Schoenenberger,Maria Fernanda; Piemonte,Mariana da Rocha; Souza,Patrícia S. de A.; Scühli,Guilherme Schnell e; Mucciatto,Mariele B.; Mazzuco,Roseli
Spatial variability in the concentration of total bacteria, saprophytes and coliforms abundance was investigated in surface waters of Paranaguá and Antonina Bays. Six points along a profile from the entrance of Paranaguá Bay to the innermost part of Antonina Bay, were sampled on February 26, 1997. Temperature, salinity, dissolved oxygen, pH, particulate organic carbon, water transparency and seston were also measured. Determination of total bacterial abundance and biomass were made with the epifluorescent method. Saprophytic bacteria counts were conducted with ZoBell 2216E culture medium with fresh and 32? water and the coliform MPN was enumerated with the chromogenic substrate method....

9. Fenotipagem de bactérias isoladas em hemoculturas de pacientes admitidos na unidade clínica de terapia intensiva de um hospital escola - Lara Stefânia Netto de Oliveira Leão
Introduction: In hospitals the bloodstream infections represent a serious complication in critical patients The detection of bacteria in blood cultures is considered an important diagnosis instrument This study aimed to detect and characterize bacteria from blood of clinical intensive care unit admitted patients of a teaching hospital in Goiânia-Goiás in the period of April/2003 to April/2004 Methods: The blood samples were seeded in brean heart infusion broth (Bacto™ - BD Diagnostic Systems/ USA) incubated until 7 days at 37oC and subcultived on chocolate agar to isolated microorganisms The isolated bacteria were identified by biochemical / enzymatic test and automation technique...

10. Bacteria and protozoa populations in groundwater in landfill area in São Carlos, SP - Fusconi,Roberta; Godinho,Mirna Januária Leal
The microbial populations of groundwaters were analyzed in a region under the influence of a landfill (piezometer L12) in the town of São Carlos, São Paulo, Brazil, and in an area not influenced by the landfill (piezometer L5). Heterotrophic bacteria were counted by spread plate method and the number of protozoa was estimated by the most probable number method. There was a larger number of organisms in well L12, with a mean value of 15.76 x 104 CFU/ml for bacteria and 9.7 MPN/ml for protozoa, whereas the mean values for piezometer L5 were 2.88 x 104 CFU/ml for bacteria and...

11. Isolamento de bactérias resistentes a cromo hexavalente e purificação parcial da enzima redutora de cromo do Bacillus sp. ES29 - Conceição, Daniele Priscila da
A redução do Cr(VI) para Cr(III) diminui a toxidade deste metal no ambiente uma vez que, o Cr(III) é insolúvel às membranas biológicas. Assim a redução microbiana do Cr(VI) é uma alternativa para reduzir os impactos ambientais causados por este metal, utilizado em diversos processos industriais. O objetivo deste trabalho foi selecionar microrganismos a partir de solo contaminado com cromo, caracterizar sua capacidade de redução do Cr(VI) durante o crescimento celular e purificar parcialmente a enzima cromo redutase do Bacillus sp. ES29, através da precipitação com sulfato de amônio (45-75%), cromatografia de gel filtração (Sephadex G-25) e cromatografia de interação...

12. Characterisation of volatile compounds produced by bacteria isolated from the spoilage flora of cold-smoked salmon - JOFFRAUD, Jean-Jacques; LEROI, Francoise; ROY, Caroline; BERDAGUE, J
This study investigated the volatile compounds produced by bacteria belonging to nine different bacterial groups: Lactobacillus sake, L. farciminis, L. alimentarius. Carnobacterium piscicola, Aeromonas sp., Shewanella putefaciens. Brochothrix thermosphacta, Photobacterium phosphoreum and Enterobacteriaceae isolated from cold-smoked salmon. Each bacterial group was represented by several strains. In addition, combinations of the groups were examined as well. Sterile blocks of cold-smoked salmon were inoculated, vacuum-packed and stored at 6 degreesC. After 40 days of storage at 6 degreesC, aerobic viable count and pH were recorded, the volatile fraction of the samples was analysed by gas chromatography-mass spectrometry (GC-MS). and spoilage was assessed...

13. F-type ATPases and their role in the physiology of extremophilic bacteria - Ferguson, Scott A
The F[1]F[O]-ATP synthase found in bacteria, mitochondria, and chloroplasts is responsible for synthesizing ATP from the precursors ADP and P[i]. In bacteria, the enzyme is used to synthesize ATP when the electrochemical gradient of protons ([Delta][mu]H⁺) or sodium ions ([Delta][mu]Na⁺) is high, and the phosphorylation potential is low inside the cell. Conversely, the enzyme hydrolyses ATP to generate a [Delta][mu]H⁺ or [Delta][mu]Na⁺ when these gradients are low, and the phosphorylation potential is high inside the cell. This is coupled to intracellular pH homeostasis in some fermentative bacteria. The aim of this project was to determine the role(s) of the F[1]F[O]-ATP...

14. Identificação e quantificação de metais pesados, parasitas e bactérias em esgoto bruto e tratado da Estação de Tratamento de Esgoto de Ribeirão Preto - SP - Karina Aparecida de Abreu Tonani
Nos países em desenvolvimento, onde podemos encontrar áreas urbanas densamente povoadas com precárias condições de saneamento básico, o esgoto sem tratamento é responsável por um grande número de doenças de veiculação hídrica. Além da carga microbiológica (bactérias, vírus, ovos/larvas de helmintos e protozoários), pode também conter diversos poluentes químicos que afetam a saúde humana, dentre eles os metais pesados. Este estudo teve como objetivo avaliar os níveis de metais pesados, bem como identificar e quantificar parasitas e coliformes totais e fecais em efluentes urbanos, antes e após o tratamento de esgoto pelo sistema lodos ativados da Estação de Tratamento de...

15. Desulfurobacterium atlanticum sp nov., Desulfurobacterium pacificum sp nov and Thermovibrio guaymasensis sp nov., three thermophilic members of the Desulfurobacteriaceae fam. nov., a deep branching lineage within the Bacteria - L' HARIDON, S; REYSENBACH, A.L.; TINDALL, B. J.; SCHONHEIT, P; BANTA, A; JOHNSEN, U; SCHUMANN, P; GAMBACORTA, A; STACKEBRANDT, E; JEANTHON, C
Three thermophilic, anaerobic, strictly chemolithoautotrophic, sulphur- and/or thiosulphate-reducing bacteria, designated SL17(T), SL19(T) and SL22(T), were isolated from deep-sea hydrothermal samples collected at 13 degrees N (East Pacific Rise), Guaymas Basin (Gulf of California) and 23 degrees N (Mid-Atlantic Ridge), respectively. These strains differed in their morphology, temperature range and optimum for growth, energy substrates and 16S rRNA gene sequences. The G + C content of the genomic DNA was 41 mol% (SL22(T)), 42 mol% (SL17(T)) and 46 mol% (SL19(T)). Comparative analysis of phenotypic and phylogenetic traits indicated that strains SL17(T) and SL22(T) represented two novel species of the genus Desulfurobacterium...

16. Ichthyopathogenic bacteria in mariculture. - VIGNEULLE, Martine
Bacterial infections occurred during the development of marine fish farming of species such as turbot, sea-bass, sea-bream or salmon and trout. The main-specific bacteria involved in these diseases observed belong to 3 groups: the Vibrionaceae for Vibrio anguillarum (type 408) and Aeromonas salmonicida , the causative agents of respectively vibriosis and furinculosis; the Corynebacteriaceae for Renibacterium salmoninarum , responsible for bacterial kidney disease (BKD), the Enterobacteriaceae for Yersinia ruckeri , the causative agent of enteric redmouth disease. The clinical signs typical of those diseases always depend on the rearing and environmental conditions. The losses resulting from these bacterial diseases and...

17. Seleção de bactérias queratinolíticas provenientes de solos brasileiros - Bach, Evelise
Muitos estudos vêm sendo desenvolvidos com microrganismos produtores de queratinases pelo seu potencial biotecnológico e por serem causadores de doenças em animais. Porém, muito antes do seu papel biotecnológico, estas enzimas têm relevância ecológica realizando a reciclagem destes resíduos queratinosos na natureza. As bactérias reportadas como queratinolíticas pertencem principalmente aos gêneros Bacillus e Streptomyces, porém estudos recentes mostram que a diversidade de bactérias queratinolíticas deve ser muito maior. Este trabalho tem como objetivo selecionar e identificar bactérias cultiváveis provenientes de solos de matas nativas brasileiras, que sejam produtoras de queratinases para contribuir com o conhecimento da diversidade desta característica na...

18. (Interrelations between anaerobic bacteria communities of marine sediments.). - MARTY, D
The mineralization of cellulose was examined in mono and cocultures of marine anaerobic bacteria (cellulolytic bacteria, fermentative non-cellulolytic bacteria and methane-producing bacteria). These studies displayed interactions between these groups of microorganisms: inhibition relationships (inhibition of methanogens during active growth of fermentative bacteria) and syntrophic relationships (growth of fermentative non-cellulolytic bacteria depended on metabolites produced by cellulolytic bacteria; increased in rate of cellulose hydrolysis in presence of fermentative non-cellulolytic bacteria; interspecies H sub(2) transfer reaction between fermentative bacteria and methane-producing bacteria).

19. Bactérias diazotróficas associadas a raízes e colmos de cultivares de sorgo - Bergamaschi, Clarissa
Os danos ao ambiente, bem como os custos econômicos relacionados à adubação nitrogenada têm estimulado a busca por alternativas que possam diminuir a utilização deste fertilizante sem que haja diminuição na produtividade. Uma das possibilidades é a utilização de bactérias diazotróficas que podem se associar a plantas de sorgo para fixar nitrogênio gasoso (N2) e/ou produzir substâncias promotoras de crescimento de plantas (PCPs). Outra possibilidade é a seleção de genótipos eficientes na associação com bactérias diazotróficas, já que a eficiência na associação depende de características específicas das plantas. Deste modo, o presente estudo objetivou avaliar a ocorrência e a localização...

20. Objectives - After Reading This; E. Prokaryotic Genomes; F. Growth; Gene Exchange; D. Metabolic; Relationships Oxygen; B. Domain Bacteria (eubacteria
tem of classification and explain how it differs from previous systems. 3. Using a diagram or micrograph, distinguish among the three most common shapes of prokaryotes. 4. Describe the structure and functions of prokaryotic cell walls. 5. Distinguish between the structure and staining properties of gram-positive and gram-negative bacteria. 6. Explain why disease-causing gram-negative bacterial species are generally more pathogenic than disease-causing gram-positive bacteria. 7. Describe three mechanisms motile bacteria use to move. 8. Explain how prokaryotic flagella work and why they are not considered to be homologous to eukaryotic flagella. 9. Indicate where photosynthesis and cellular respiration take place...

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