Thesis (Ph. D.)--University of Alberta, 2001. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Dept. of Medical Microbiology and Immunology, University of Alberta. Includes bibliographical references.

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Orientador: Humberto Márcio Santos Milagre / Banca: Paulo José Samenho Moran / Banca: José Augusto Rosário Rodrigues / Resumo: As cianobactérias são bactérias fotossintetizantes que podem ser encontradas nos mais variados ambientes. Algumas espécies de cianobactérias produzem toxinas denominadas cianotoxinas. As cianotoxinas denominadas microcistinas (MCs) são heptapeptídeos cíclicos hepatotóxicos produzidas durante florações de cianobactérias. Sua detecção e quantificação em mananciais são de grande importância devido aos danos a saúde humana que essas microcistinas podem causar. Atualmente, a técnica MALDI-TOF-MS tem se mostrado uma eficiente ferramenta para a análise de microcistinas, e recentes estudos tem reportado seu uso na quantificação destas. Diante do exposto, o objetivo desta dissertação foi a avaliação de diferentes matrizes e diferentes métodos de preparo de amostra para MALDI-MS visando a detecção e quantificação das microcistinas. Com a finalidade de alcançar o melhor método de quantificação das microcistinas, nove matrizes para MALDI, onze métodos de preparo de amostra mais um método que foi adaptado por nosso grupo de pesquisa, o método Vacuum drying adaptado, e dois padrões comerciais de microcistinas, MC-LR e MC-RR, foram utilizados. A avaliação dos métodos de preparo de amostra foi realizada utilizando como matriz o ácido α-ciano-4-hidroxicinâmico (HCCA) e o peptídeo angiotensina I como padrão interno. Os métodos foram avaliados com relação aos seus coeficientes de variação (CV), suas cristalizações e espectros obtidos, utilizando a MC-RR como amostra. O método Vacuum drying adaptado apresentou os melhores resultados e sua curva analítica foi construída utilizando ambas as variantes de microcistinas. O limite de detecção (MLD) e o limite de quantificação (LDQ) também foram calculados. Cada curva da variante de microcistina apresentou excelente linearidade e os valores de r variaram entre 0,98-99, demonstrando que o método é adequado para a quantificação destas. Após as análises dos... / Abstract: Cyanobacteria are photosynthetic bacteria that can be found in diverse environments. Some species of cyanobacteria produce toxins denominated cyanotoxins. The cyanotoxins called microcystins (MCs) are hepatotoxic cyclic heptapeptides produced during cyanobacterial blooms. Its detection and quantification in springs are of great importance due to damage to human health that these microcystins can cause. Currently, MALDI-TOF-MS technique has been shown to be an efficient tool for the analysis of microcystins, and recent studies have reported its use in the quantification of these. On the exposed, the aim of this thesis was to evaluate the different matrices and different methods of sample preparation for MALDI-MS aimed at the detection and quantification of microcystins. With the aim of achieving the best method of quantification of microcystins nine matrices for MALDI eleven methods of sample preparation over a method that was adapted by our research group, the adapted vacuum drying method, and two commercial standards of microcystins, MC-LR, and MC-RR, are used. The evaluation methods of sample preparation was performed using as matrix the α- cyano-4-hydroxycinnamic acid (CHCA) and the angiotensin I as internal standard. The methods were evaluated with respect to their coefficients of variation (CV), their crystallization and spectra obtained using the MC-RR as a sample. The adapted vacuum drying method showed the best results and their analytical curve was constructed using both variants of microcystins. The limit of detection (MDL) and the limit of quantification (LOQ) were also calculated. Each curve variant of microcystin showed excellent linearity and r values ranged from 0.98 to 99, showing that the method is suitable for quantifying these. After analysis of the methods of sample preparation, the nine matrices were evaluated with respect to CV, crystallization and spectra, using the MC-RR as a sample. The best results were obtained... / Mestre

Pseudomonas species are Gram-negative bacteria most abundant in soil and water bodies, with the capacity to thrive in varied environments. They are largely associated with resistant pathogenic bacteria linked to human and plant diseases. Species such as Pseudomonas aeruginosa have been particularly targeted as case studies due to the extremity to which they pose a threat to human health. With more focus directed at using these species for biocontrol and bioremediation purposes, their role in bioactive compound production may be equally important. As the crisis on antimicrobial resistance still persists, the need for effective antimicrobial compounds is ever more urgent and solutions may possibly still be dormant in bacterial species whose potential has not been fully investigated. On a bid to source out potential antimicrobial compound producers, soil samples were collected from Hogback forest reserve in the province of the Eastern Cape, South Africa. For bacterial screening, M1 and R2A agar were used and the cultures grown at 37˚C for a period of seven days. After the presumed Pseudomonas species were identified, antimicrobial production was determined by submerged fermentation method using nutrient broth as media of choice. Active isolates were further studied to determine the optimum conditions which best facilitate for antimicrobial compound production, with parameters such as temperature (25˚C – 40˚C) and pH (4 – 9) considered. The role plasmids play in antimicrobial compound production was also investigated. Each isolate was grown in fermentation media containing Sodium dodecyl sulphate and Ethedium Bromide, at varying concentrations, to facilitate for plasmid curing. With each sample, distinct colonies were identified with varying pigmentations most dominant being a cream colour. The identity of the isolated strains was achieved through sequencing of 16S rDNA. Phylogenetic analysis showed that isolate A16 had 80 percent homology with Pseudomonas plecoglossicida strain P4 and share a close ancestor with isolates Y52 and Y81, also isolate Y89 showed a 90 percent homology with Pseudomonas sp. Co-11a. With the exception of isolate A16, the isolates which were active against Gram-negative bacteria lost activity as the screening processes continued. When looking at temperature variations, isolates Y81 and A16 were highly active with maximum activity observed at 35˚C while Y89 performed best at 25˚C and Y52 showed constant activity across all studied temperatures. The plasmids in all isolates were found to be 48.5 kb in size with the exception of isolate Y89 which was 20 kb. The plasmids were cured at concentrations of (1 mg/ml; 5 mg/ml; 7 mg/ml; 10 mg/ml; 11 mg/ml) SDS and (125 μg/ml; 6.5 μg/ml; 5μg/ml) EtBr. The curing process also showed changes in both the antimicrobial activity of the isolates as well as their physical characteristics. The isolates are the first reported Pseudomonas species from Hogsback forest reserve with the ability to produce antimicrobial compounds which are active against Gram-positive and Gram-negative bacteria. These mesophilic bacteria also show that plasmids do not pay any role in the production of antimicrobial compounds and that the biosynthesis genes are highly likely to be chromosomal borne meaning that the production cannot be linked to horizontal transfer of genes. Therefore, these isolated Pseudomonas species provide a potential reservoir of antimicrobial compounds which may play an important role in the antimicrobial resistance phenomenon.

Made available in DSpace on 2016-02-05T18:29:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-06. Added 1 bitstream(s) on 2016-02-05T18:33:55Z : No. of bitstreams: 1 000856518_20170619.pdf: 389927 bytes, checksum: 4be3b8327beb9325c295271ea9eaffa2 (MD5) Bitstreams deleted on 2017-06-19T16:12:33Z: 000856518_20170619.pdf,. Added 1 bitstream(s) on 2017-06-19T16:13:18Z : No. of bitstreams: 1 000856518.pdf: 1255973 bytes, checksum: 911854ad6a713ea1a328b649f79c9d4d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Xanthomonas. citri subsp. citri (Xac) é o agente causal do cancro cítrico, uma das doenças mais graves que afetam plantas cítricas de importância comercial em todo o mundo. O controle eficaz para o cancro cítrico constitui na eliminação de plantas infectadas em programas rigorosos para conter a propagação da bactéria. No entanto, o relaxamento recente nas políticas para combater cancro cítrico em áreas como o estado de São Paulo - Brasil, está a contribuir para a propagação da doença. O conhecimento da biologia deste patógeno de plantas e também dos mecanismos envolvidos na interação planta-patógeno são de grande importância para apoiar o desenvolvimento de estratégias para lidar com o cancro cítrico. Um trabalho recente de nosso grupo demonstrou que os mutantes X. citri com disrupção do gene parB são comprometidos na segregação cromossômica e na capacidade de produzir os sintomas da doença na planta. No presente trabalho, nós estendemos nossas caracterizações, avaliando os efeitos da falta de parB em mutantes X. citri através de uma deleção limpa. ParB é uma proteína de ligação ao DNA e está envolvida no processo de segregação cromossômica através de interação com outras proteínas. Devido à dificuldade de deleção de genes envolvidos neste processo em X. citri, o nocaute de parB foi realizado numa variante abrigando um plasmídeo replicativo capaz de expressar cópias extras de ParB (ParB-TAP) sob o controle de para (promotor de arabinose). A viabilidade de X. citri parB nocaute (XacΔparB-pLAC2) foi avaliada em experimentos de curva de crescimento e em comparação com a estirpe do tipo selvagem, em condições de repressão ou de indução de parB-tap ligado a este promotor; O objetivo foi explorar as condições de depleção e superexpressão de ParB e seus efeitos através da caracterização do referido promotor. Em seguida, X. citri parB nocaute foi visualizado por microscopia de... / Xanthomonas citri ssp. citri (Xac) is the causal agent of citrus canker, one of the most severe diseases that affect citrus plants of commercial importance around the world. An effective control for citrus canker constitutes the elimination of infected plants in rigorous programs to contain the spread of the bacteria. However, recent relaxation in the policies to combat citrus canker in areas such as the state of São Paulo, Brazil, the major orange juice producer in the world, are contributing to the spread of the disease. Therefore, knowledge of the biology of this plant pathogen and also of the mechanisms involved in plant-pathogen interaction are of great importance to support the development of strategies to deal with citrus canker. Recent work from our group demonstrated that X. citri mutants disrupted for parB are compromised in chromosome segregation and are unable to produce disease symptoms in plant. In the present work, we extended our characterizations by evaluating the effects of a lack of ParB in X. citri mutants carrying a clean deletion of its coding DNA. ParB is a DNA binding protein and is involved in chromosome segregation process through interaction with other proteins. Because of difficult in genes deletion involved this process in X. citri, the parB gene was deleted in a X. citri variant harboring a replicative plasmid able to express extra copies of ParB (ParB-TAP) under the control of the para (arabinose promoter). The viability of the X. citri parB knockout was assessed in growth curve experiments and compared with the wild type strain under different conditions of parB-tap repression or induction. The aim was to explore the conditions depletion and overexpression of ParB and its effects through the characterization of para in X. citri Thus, the X. citri parB knockout was visualized under differential interference contrast (DIC) microscopy in order to detect morphological alterations normally expected from ...

Made available in DSpace on 2014-06-11T19:33:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02-16Bitstream added on 2014-06-13T20:44:56Z : No. of bitstreams: 1 gama_nmsq_dr_jab.pdf: 724899 bytes, checksum: 04590f244015497a275594b6f685ba26 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Para as aves, a água é o nutriente essencial mais importante, sendo responsável pela maioria das funções do organismo. Em 2004 avaliou-se a qualidade da água utilizada em 20 granjas de postura comercial de Bastos/SP, Brasil, colhendo-se amostras dos poços, reservatórios e galpões. Nas amostras dos poços determinou-se a concentração de alumínio, cálcio, chumbo, cloro, cobre, enxofre, ferro, fósforo, magnésio, nitrito, potássio, selênio, sódio, sulfatos, zinco, pH e dureza. Nas amostras colhidas nos períodos de chuva e estiagem, realizaram-se as contagens de coliformes totais e fecais, estreptococos fecais, Pseudomonas aeruginosa e pesquisou-se Escherichia coli , Salmonella sp e Pasteurella multocida. A dureza da água de 35% das propriedades apresentou valores entre 60 - 110 mg CaCO3/L, em 45% o pH foi =6 e nenhuma apresentou pH >8. Entre as propriedades 50% apresentaram níveis de NO3-N =3 mg/L. Para todos os microrganismos pesquisados, o galpão de aves apresentou as maiores taxas de amostras positivas nos períodos de chuva e estiagem, ocorrendo a diminuição da % de isolamento no período de estiagem. A contagem bacteriana foi maior nas amostras de água do galpão, nos dois períodos de colheita. No reservatório, após a adição de cloro à água, o número de coliformes totais diminuiu e não houve detecção de coliformes fecais, estreptococos fecais e Pseudomonas aeruginosa. Em nenhuma das 440 amostras de água analisadas, nos períodos de chuva e estiagem, foram detectadas Salmonella sp e Pasteurella multocida. / Water is considered the most important essential nutrient, for chickens, being responsible for most of the organism functions. In 2004, the quality of the water used in 20 laying hens farms from Bastos/SP, Brazil, was tested, picking samples from wells, water tanks and laying hens house. It was determinated in the well-water samples the concentration of aluminum, calcium, lead, chlorine, copper, iron, phosphorus, magnesium, nitrate, nitrite, potassium, selenium, sodium sulfate, zinc, pH and strength. In the water samples, collected in the rainy and dry seasons, were counted the total coliforms, fecal coliforms, fecal streptococci, Pseudomonas aeruginosa and was done the research of Escherichia coli , Salmonella sp e Pasteurella multocida. The strengths values of 35% of the farms was between 60-110 mg CaCO3/L, in 45%, the pH was =6 and no farms presented pH >8. Among the farms 50% presented levels of NO3-N =3. For all microorganism researched, the laying hens house presented the higher taxes of positives samples during the rainy or dry seasons, occurring a reduction of isolation taxes in the dry season. Both periods of collection the number of total coliforms; fecal coliforms; streptococci and Pseudomonas aeruginosa was higher in the samples from the laying hens houses. In the water tank, after chlorine addiction to the water, the number of total and fecal coliforms decreased and there wasn't detection of fecal streptococci and Pseudomonas aeruginosa. In none of the 440 water samples analyzed, in the rainy nor in the dry seasons, Salmonella sp and Pasteurella multocida were detected.

Made available in DSpace on 2015-06-17T19:34:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-12. Added 1 bitstream(s) on 2015-06-18T12:49:05Z : No. of bitstreams: 1 000832493.pdf: 1769807 bytes, checksum: e6c5bb7d9bcec2a173427a67060a8dce (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As cianobactérias são bactérias fotossintetizantes que podem ser encontradas nos mais variados ambientes. Algumas espécies de cianobactérias produzem toxinas denominadas cianotoxinas. As cianotoxinas denominadas microcistinas (MCs) são heptapeptídeos cíclicos hepatotóxicos produzidas durante florações de cianobactérias. Sua detecção e quantificação em mananciais são de grande importância devido aos danos a saúde humana que essas microcistinas podem causar. Atualmente, a técnica MALDI-TOF-MS tem se mostrado uma eficiente ferramenta para a análise de microcistinas, e recentes estudos tem reportado seu uso na quantificação destas. Diante do exposto, o objetivo desta dissertação foi a avaliação de diferentes matrizes e diferentes métodos de preparo de amostra para MALDI-MS visando a detecção e quantificação das microcistinas. Com a finalidade de alcançar o melhor método de quantificação das microcistinas, nove matrizes para MALDI, onze métodos de preparo de amostra mais um método que foi adaptado por nosso grupo de pesquisa, o método Vacuum drying adaptado, e dois padrões comerciais de microcistinas, MC-LR e MC-RR, foram utilizados. A avaliação dos métodos de preparo de amostra foi realizada utilizando como matriz o ácido α-ciano-4-hidroxicinâmico (HCCA) e o peptídeo angiotensina I como padrão interno. Os métodos foram avaliados com relação aos seus coeficientes de variação (CV), suas cristalizações e espectros obtidos, utilizando a MC-RR como amostra. O método Vacuum drying adaptado apresentou os melhores resultados e sua curva analítica foi construída utilizando ambas as variantes de microcistinas. O limite de detecção (MLD) e o limite de quantificação (LDQ) também foram calculados. Cada curva da variante de microcistina apresentou excelente linearidade e os valores de r variaram entre 0,98-99, demonstrando que o método é adequado para a quantificação destas. Após as análises dos... / Cyanobacteria are photosynthetic bacteria that can be found in diverse environments. Some species of cyanobacteria produce toxins denominated cyanotoxins. The cyanotoxins called microcystins (MCs) are hepatotoxic cyclic heptapeptides produced during cyanobacterial blooms. Its detection and quantification in springs are of great importance due to damage to human health that these microcystins can cause. Currently, MALDI-TOF-MS technique has been shown to be an efficient tool for the analysis of microcystins, and recent studies have reported its use in the quantification of these. On the exposed, the aim of this thesis was to evaluate the different matrices and different methods of sample preparation for MALDI-MS aimed at the detection and quantification of microcystins. With the aim of achieving the best method of quantification of microcystins nine matrices for MALDI eleven methods of sample preparation over a method that was adapted by our research group, the adapted vacuum drying method, and two commercial standards of microcystins, MC-LR, and MC-RR, are used. The evaluation methods of sample preparation was performed using as matrix the α- cyano-4-hydroxycinnamic acid (CHCA) and the angiotensin I as internal standard. The methods were evaluated with respect to their coefficients of variation (CV), their crystallization and spectra obtained using the MC-RR as a sample. The adapted vacuum drying method showed the best results and their analytical curve was constructed using both variants of microcystins. The limit of detection (MDL) and the limit of quantification (LOQ) were also calculated. Each curve variant of microcystin showed excellent linearity and r values ranged from 0.98 to 99, showing that the method is suitable for quantifying these. After analysis of the methods of sample preparation, the nine matrices were evaluated with respect to CV, crystallization and spectra, using the MC-RR as a sample. The best results were obtained... / FAPESP: 2012/03663-8

Made available in DSpace on 2015-01-26T13:21:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-27Bitstream added on 2015-01-26T13:30:40Z : No. of bitstreams: 1 000797018.pdf: 979811 bytes, checksum: d1c6e8376b7684ecf71b56da793dd4b3 (MD5) / Os estabelecimentos de saúde e as superfícies inanimadas que cercam o paciente guardam íntima relação com as infecções relacionadas a assistência e a saúde, sendo importantes focos de contato e de transmissão de agentes patogênicos e podem ser transferidos para as mais diversas superfícies através do contato direto e indireto. Existem inúmeras pesquisas que retratam que os artigos hospitalares podem se tornar veículos de disseminação, comprometendo a segurança do paciente. Diante desta problemática, este estudo objetivou-se em analisar as condições bacteriológicas de superficie de poltronas hematológicas para hemodiálise. Após aprovação do Comitê de Ética em pesquisa foi realizada a randomização das poltronas, duplo cego e iniciou a amostragem das quatro cadeira nos sete procedimentos em cinco locais diferentes na poltrona. O produto utilizado para higienização de rotina na unidade foi o álcool a 70% com compressa hospitalar composta de tecido 100% algodão em dimensão de 30 x 30 cm, umedecida com 40 ml de álcool 70%. Para amostragem bacteriológica utilizou-se campo estéril fenestrado para garantir coleta sempre no mesmo local utilizando Swab. O Swab foi transportado para o laboratório em meio de cultura gel Stuart para identificação. Após foi realizado teste de antibiograma das bactérias isoladas e teste de sensibilidade “in vitro” utilizando método de Kirby e Bauer com modificações conforme descrito por Corrêa (1988). Para o teste “in vitro” utilizou-se três desinfetantes frente as bactérias isoladas das poltronas que são consideradas de grande importância no controle de infecção hospitalar. O resultado demostrou que a maior unidade formadora de colônia foi em relação ao Staphilococcus sp, seguido de bacilus Gram positivo, Staphilococcus aureus, Pseudomonas, Enterobacter cloacae e Acinetobacter, com predominância do Staphilococcus sp em todas as ... / Health facilities and inanimate surfaces surrounding the patient keep close relation with infections related to care and health, with important centers of contact and transmission of pathogens and can be transferred to many different surfaces through direct and indirect contact. There are numerous studies that show that the hospital items can become vehicles of dissemination, compromising patient safety. Faced with this problem, this study aimed to analyze the bacteriological conditions in the surface of hematologic arm for hemodialysis. After approval by the Research Ethics Committee of the randomization arm, double- blind trial was performed and started sampling the four chair the seven procedures in five different locations in the chair. The product used for routine cleaning of the unit was 70% alcohol with hospital pad composed of 100% cotton in size 30 x 30cm, moistened with 40 ml of 70% ethanol. Bacteriological sampling was used to ensure fenestrated sterile field in the same site collection using Swab. The swab was transported to the laboratory in culture medium gel Stuart for identification. After testing, was performed antibiogram of isolates and sensitivity test in vitro using Kirby and Bauer method with modifications as described by Cooke (1988). For in vitro test used three disinfectants front seats of the isolated bacteria that are considered of great importance in the control of hospital infection. The result demonstrated that the largest colony-forming unit was compared to Staphylococcus sp, followed by Gram-positive bacillus, Staphylococcus aureus, Pseudomonas, Enterobacter cloacae, and Acinetobacter, predominantly Staphylococcus sp on all surfaces of the chair, with predominance in the left arm armchair coinciding with the arm of the patient who has an arteriovenous fistula (70%). Regarding sensitivity, Acinetobacter were sensitive to all antibiotics tested, whereas Pseudomonas were sensitive to sulfa / trimethoprim, ...

Made available in DSpace on 2014-06-11T19:27:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-22Bitstream added on 2014-06-13T19:55:56Z : No. of bitstreams: 1 meneghine_ak_me_jabo.pdf: 500432 bytes, checksum: 2720a46642e38f1bfc0ff5d7be11a770 (MD5) / A aquicultura é uma atividade que está em contínuo crescimento, desta forma os ecossistemas aquáticos utilizados para tal atividade acabam sofrendo alterações nas condições da água e na comunidade microbiana do local. No presente trabalho, compararam-se as comunidades bacterianas presentes em águas de dois viveiros de piscicultura, um utilizado como reservatório de água (V1) e o outro com condições de elevada carga de nutrientes (V4), os quais estão inseridos em um sistema sequencial com fluxo contínuo de água (seis viveiros). A escolha dos viveiros V1 e V4, foi baseada em estudos anteriores no qual foi evidenciado um alto grau de eutrofização neste local. As coletas de água foram realizadas em dois períodos distintos um na seca (Julho e Agosto/2012) e outro na chuva (Janeiro e Fevereiro/2012). A comunidade bacteriana foi avaliada através do sequenciamento do gene 16S rRNA. A população bacteriana variou significativamente entre os dois viveiros e segundo a estação anual, seca ou chuva. No viveiro 1 observou-se uma grande proporção de Proteobacterias, em ambos os períodos, entretanto houve mudanças nas classes deste grupo, a maioria β-Proteobacterias (chuvas) e uma proporção equivalente de β e α-Proteobacterias (seca). No viveiro 4, foi observada uma alta frequência de Cyanobacterias principalmente na estação de seca, aproximadamente 80% da população bacteriana do local, enquanto no período de chuvas este grupo foi menor. A comparação da população bacteriana dos dois viveiros estudados em épocas distintas mostrou que as bactérias nestes locais variam de acordo com o período hidrológico e estão intimamente ligadas com a concentração de nutrientes do local. Estas diferenças são importantes na participação dos ciclos biogeoquímicos, principalmente envolvendo os ciclos do nitrogênio e fósforo e a sanidade do sistema aquático. / The aquaculture is an activity that is continuous growing, in this way aquatic ecosystems used for such activity end up suffer changes in water conditions and microbial community local. In this study, we compared the bacterial communities present in waters of two fish farm ponds, a used as water reservoir (V1) and the other with conditions of high nutrient load (V4), which are inserted in a sequential system with continous water flow (six ponds). The choice of nurseries V1 and V4 was based on previous studies in which evidenced a high degree of eutrophication in this location. The water sampling were conducted in two distinct periods one in dry season (July and August/2012) and another in the rain (January and February/2012). The bacterial community was assessed by sequencing the 16S rRNA. The bacterial population varied significantly between the two ponds and according to season annual, dry or rain. In the pond 1 there was a large proportion of proteobacteria, in both periods, however there were changes in the classes of this group, most β-Proteobacteria (rain) and an equivalent proportion of β and α-proteobacteria (dry). In pond 4, we observed a high frequency of cyanobacteria mainly during the dry season, approximately 80% of the bacterial population of the place, while in the rainy season this group was lower. A comparison of the bacterial population of the two ponds studied at different times showed that the bacteria at these sites varies according to the period hydrological and are closely linked with nutrient concentration local. These differences are important in the participation in biogeochemical cycles, especially involving the cycles of nitrogen and phosphorus and health of the aquatic system.