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Sample records for bacteriana por lactococcus

  1. Controle biológico da murcha bacteriana do tomateiro, por Pseudomonas spp. fluorescentes

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    Peixoto, Ana Rosa

    1997-01-01

    Esta revisão bibliográfica teve como objetivo avaliar o potencial de antagonismo de espécies de Pseudomonas fluorescentes a Pseudomonas solanacearum, agente causal da murcha bacteriana do tomateiro. Devido a dificuldade encontrada nas estratégias utilizadas para o controle da Murcha Bacteriana por meio de métodos convencionais, alguns outros tem sido estudados, como o uso de microrganismos benéficos. As rizobactérias vem proporcionando solução viável a algumas doenças consideradas de difícil ...

  2. Tratamiento de agrandamiento gingival inducido por fenitoina asociado a placa bacteriana

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    Carmen Julia Rovira; Jennifer Orozco Páez; Antonio Díaz Caballero

    2013-01-01

    ResumenLa ingesta de algunos medicamentos puede producir un sobre crecimiento de las encías. Se reportan medicamentos tales como los bloqueadores de los canales de calcio, inmunosupresores, anticonvulsivantes que producen estos efectos adversos. Múltiples casos de agrandamientos gingivales están asociados a la ingesta de Fenitoína. El tratamiento de los agrandamientos gingivales inducidos por drogas por lo general es quirúrgico, pero mantener un buen control de placa bacteriana puede evitar e...

  3. Endocardite por lactococcus garvieae: primeiro relato de caso da América Latina

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    Tatiana Franco Hirakawa

    2011-11-01

    Full Text Available Lactococcus garvieae, patógeno zoonótico emergente, é responsável por mastite em ruminantes e septicemia em peixes. Embora seja considerado oportunista e raramente causar infecções em humanos, sua incidência deve estar subestimada devido à dificuldade do diagnóstico. Há pouquíssimos relatos de osteomielite, abscesso hepático e peritonite, e apenas nove casos descritos na literatura mundial de endocardite. Relatamos o primeiro caso de endocardite por Lactococcus garvieae da América Latina em paciente portadora de prótese valvar metálica, com quadro de febre diária, calafrios, nodos de Osler e seis hemoculturas positivas para Lactococcus garvieae, que preenchiam os critérios de Duke para o diagnóstico de "endocardite infecciosa definitiva"

  4. Vaginosis bacteriana por Gardnerella vaginalis: Nuevas enseñanzas desde la ecología molecular

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    Andrés Zúñiga

    2015-06-01

    Full Text Available La vaginosis bacteriana (VB, es la afección vaginal más frecuente en las mujeres en edad reproductiva generada por un desbalance en el ecosistema vaginal que ocasiona complicaciones severas para la salud reproductiva. Existen hipótesis de origen biológico que relacionan la presencia de organismos como Gardnerella vaginalis, Prevotella sp, Atopobium vaginae como la causa más frecuente relacionada con la vaginosis, los cuales logran desplazar poblacionalmente microorganismos con capacidad protectora del epitelio vaginal como Lactobacillus crispatus y Lactobacillus jensenii. En la actualidad y de acuerdo a la OMS, la vaginosis bacteriana estaría implicada en alteraciones durante el embarazo como parto pre termino, bajo peso al nacer, corioamnionitis, ruptura prematura de membranas (RPM, endometritis post parto, entre otras. En los últimos años, con base estudios apoyados en datos de patrones moleculares, así como tecnología de análisis de genomas, surge una visión mucho más completa de condiciones ecológicas y agentes participantes en la vaginosis bacteriana.

  5. Tratamiento de agrandamiento gingival inducido por fenitoina asociado a placa bacteriana

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    Carmen Julia Rovira

    2013-10-01

    Full Text Available ResumenLa ingesta de algunos medicamentos puede producir un sobre crecimiento de las encías. Se reportan medicamentos tales como los bloqueadores de los canales de calcio, inmunosupresores, anticonvulsivantes que producen estos efectos adversos. Múltiples casos de agrandamientos gingivales están asociados a la ingesta de Fenitoína. El tratamiento de los agrandamientos gingivales inducidos por drogas por lo general es quirúrgico, pero mantener un buen control de placa bacteriana puede evitar en muchos casos que se presente un exagerado aumento de volumen gingival. Se presenta un caso de agrandamiento gingival en paciente masculino de 22 años de edad, bajo tratamiento antiepiléptico con fenitoína. Al examen clínico se observó aumento del volumen gingival de forma generalizada, en maxilar superior e inferior, predominante en sector anterior, produciendo ardor y sangrado durante el cepillado y la ingestión de alimentos. Al sondaje presenta múltiples pseudobolsas en los diferentes cuadrantes. La radiografía panorámica reveló pérdida ósea moderada horizontal, predominante en el sector posterosuperior, posteroinferior y anteroinferior. El plan de tratamiento consistió en fase higiénica, instrucción y motivación en higiene oral a la madre, gingivectomía y gingivoplastía en ambos maxilares. (DUAZARY 2011 No. 2, 226 - 231Abstract The importance of endodontic treatment is to achieve a complete filling and sealing of the root canal to prevent the transport of contaminants to and from root canal, with materials compatible with the surrounding tissues. Occasionally a situation may arise in which the purpose of the maintenance of working length is compromised such as overenlargement. This situation allows the extrusion of filling materials, mainly sealer cements, causing post treatment complications such as inflammatory reactions, injury to adjacent structures (orbital pain, inferior alveolar nerve injury, headache, etc., and infections

  6. Propriedades físicas, químicas e de barreira em filme formados por blenda de celulose bacteriana e fécula de batata

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    Denise M. Almeida

    2013-01-01

    Full Text Available A associação da celulose bacteriana com outros polímeros pode ser um método efetivo para aumentar suas características e estrutura, proporcionando novas aplicações industriais. O objetivo do trabalho foi verificar a influência da celulose bacteriana nas propriedades físicas, químicas e de barreira em filmes a partir de blendas de celulose bacteriana e fécula de batata. Os filmes foram produzidos segundo planejamento de mistura ternária, tendo como variáveis independentes a celulose bacteriana, fécula de batata e glicerol. Blendas com maiores concentrações de celulose bacteriana apresentaram aumento na espessura, gramatura, taxa de permeabilidade ao vapor de água e permeabilidade ao vapor de água e, redução da densidade, solubilidade, opacidade, índice de intumescimento em pH 1,8 e 8,0 (1, 10, 30 e 60 minuto. A microscopia eletrônica de varredura mostrou filmes com matriz coesa, porém irregular com presença de partículas insolúveis de celulose bacteriana. O filme de celulose bacteriana pura apresentou aumento na gramatura, opacidade, taxa de permeabilidade ao vapor de água e no intumescimento em pH 1,8 1 minuto e pH 8,0 1, 10, 30 e 60 minutos. A celulose bacteriana promoveu elevada capacidade de retenção, absorção e baixa dessorção a água, proporcionando biofilmes com características de barreira à luz e manutenção da umidade.

  7. Peritonitis bacteriana espontánea y bacteriemia por Aeromonas hydrophila Spontaneous bacterial peritonitis and bacteraemia due to Aeromonas hydrophila

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    J. J. García-Irure

    2003-12-01

    Full Text Available La peritonitis bacteriana es una complicación frecuente en los pacientes cirróticos. De los gérmenes etiológicos, Aeromonas es muy poco frecuente. Presentamos un caso clínico de un paciente cirrótico con peritonitis y bacteriemia por Aeromonas hydrophila. Este microorganismo es un bacilo gramnegativo de la familia Vibrionaceae. En el ser humano produce gastroenteritis con mucha frecuencia. De forma excepcional puede dar origen a infecciones extraintestinales, sobre todo en pacientes inmunodeprimidos. La peritonitis por Aeromonas se ha descrito en asociación a peritonitis bacteriana espontánea en pacientes cirróticos, en pacientes en diálisis peritoneal y en casos de peritonitis secundaria a perforación intestinal.Bacterial peritonitis is a frequent complication in cirrhotic patients. Amongst the aetiological germs, Aeromonas is very infrequent. We present the clinical case of a cirrhotic patient with peritonitis and bacteraemia due to Aeromonas hydrophila. This micro-organism is a Gram-negative bacillus of the Vibrionaceae family. It very frequently produces gastroenteritis in the human being. Exceptionally it can give rise to extraintestinal infections, especially in immunodepressed patients. Peritonitis due to Aeromonas has been described in association with spontaneous bacterial peritonitis in cirrhotic patients, in patients on peritoneal dialysis and in cases of peritonitis secondary to intestinal perforation.

  8. Controle biológico da murcha bacteriana do tomateiro, por Pseudomonas spp. fluorescentes Biological control of bacterial wilt of tomato by fluorescent Pseudomonas spp

    OpenAIRE

    Ana Rosa Peixoto

    1997-01-01

    Esta revisão bibliográfica teve como objetivo avaliar o potencial de antagonismo de espécies de Pseudomonas fluorescentes a Pseudomonas solanacearum, agente causal da murcha bacteriana do tomateiro. Devido a dificuldade encontrada nas estratégias utilizadas para o controle da Murcha Bacteriana por meio de métodos convencionais, alguns outros tem sido estudados, como o uso de microrganismos benéficos. As rizobactérias vem proporcionando solução viável a algumas doenças consideradas de difícil ...

  9. Influência de diferentes tipos de micro-organismos na contagem bacteriana total por citometria de fluxo do leite cru refrigerado

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    V.S.C. Sampaio

    2015-04-01

    Full Text Available Contagens bacterianas de 179 amostras de leite cru refrigerado, provenientes de diferentes bacias leiteiras de Minas Gerais, foram realizadas pelos métodos de citometria de fluxo e contagem padrão em placas. O estudo das associações entre a contagem bacteriana total e as contagens bacterianas dos diferentes grupos de micro-organismos foi realizado pela correlação de Pearson. Houve uma forte correlação positiva e significativa entre os valores de contagem de psicrotróficos (r = 0,67 e mesófilos (r = 0,70, determinados pelo método de referência, e os valores da contagem bacteriana total, determinados pela citometria de fluxo. Foi possível estabelecer uma curva de calibração para o citômetro de fluxo utilizando equações de regressão linear. As equações para a contagem bacteriana obtida por citometria de fluxo em função da contagem de mesófilos e psicrotróficos foram: log (CBI = 0,701 log mesófilos + 1,9091 e log (CBI = 0,4703 log psicrotróficos + 3,2784, respectivamente. Não foi possível estabelecer curvas de calibrações para termófilos e termodúricos, pois as correlações obtidas entre as contagens desses micro-organismos e a contagem bacteriana total, determinada por citometria de fluxo, foram fracas (r = 0,30 e 0,27, respectivamente.

  10. Characterization of bacteriocins produced by Lactococcus lactis strains Caracterização de bacteriocinas produzidas por linhagens de Lactococcus lactis

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    Izildinha Moreno

    2000-09-01

    Full Text Available Bacteriocins produced by fifteen strains of Lactococcus lactis (14 L. lactis subsp. lactis and one L. lactis subsp. cremoris were heat resistant, sensitive to several proteolytic enzymes and active over a wide range of pH. Their resistance to the heating was greatly influenced by the pH. Only the strain L. lactis subsp. lactis ITAL 383 produced a bacteriocin with a wide activity spectrum, similar to nisin of L. lactis subsp. lactis ATCC 11454. This bacteriocin inhibited closely related species and other Gram-positive microorganisms including Listeria monocytogenes and Staphylococcus aureus, but it was not active against the Gram-negative bacteria tested. The identification of partially purified antimicrobial compounds by SDS-PAGE showed that bacteriocin produced by strain ITAL 383 had the same molecular weight of nisin produced by L. lactis subsp. lactis ATCC 11454.Bacteriocinas resistentes ao aquecimento produzidas por quinze linhagens de Lactococcus lactis (14 L. lactis subsp. lactis e 1 L. lactis subsp. cremoris foram sensíveis à enzimas proteolíticas e ativas em uma ampla faixa de pH. A resistência dessas bacteriocinas ao aquecimento foi fortemente influenciada pelo pH do meio. Somente a linhagem L. lactis subsp. lactis ITAL 383 produziu uma bacteriocina com um amplo espectro de atividade, semelhante ao da nisina de L. lactis subsp. lactis ATCC 11454. Esta bacteriocina inibiu as espécies relacionadas e outros microorganismos gram-positivos, inclusive Listeria monocytogenes e Staphylococcus aureus, mas não as bactérias Gram-negativas examinadas. A identificação do composto antimicrobiano parcialmente purificado por SDS-PAGE revelou um peso molecular similar entre a bacteriocina ITAL 383 e a nisina de L. lactis subsp lactis ATCC 11454.

  11. Encefalitis bacteriana e hidrocefalia

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    Iglesias Rozas, José Rafael, 1942-

    1982-01-01

    Nueve imágenes de una encefalitis bacteriana en un niño con hidrocefalia por oclusión del acueducto de Silvio. Nine pictures of a bacterial encephalitis in a child with hydrocephalus caused by an occlusion of the Sylvian aqueduct.

  12. Contextualización de las zoonosis bacterianas y virales transmitidas por roedores

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    Juan David Rodas G

    2010-04-01

    Full Text Available Hace un poco más de 3 años, registramos dentro del postgrado de biología de la Universidad de Antioquia, la línea de investigación en zoonosis emergentes y reemergentes; motivados por los, en aquel entonces, recientes eventos, que aparentemente involucraban la transmisión de Hantavirus desde roedores (1,2, e inspirado por la experiencia recién adquirida (finales del 2004, en investigación de Arenavirus y otros virus asociados con fiebres hemorrágica en laboratorios de Estados Unidos (Universidad de Wisconsin e Instituto de Virología Humana en Baltimore, Maryland (3, nos vimos estimulados a formular y proponer, en convenio con el Instituto Colombiano de Medicina Tropical (ICMT-CES, uno de los primeros estudios de Leptospirosis en roedores urbanos en Medellín (4, y más tarde, también con el ICMT y el laboratorio de Inmuno-virología, el estudio de Hantavirus, Arenavirus y Leptospira en roedores urbanos y silvestres y en humanos de la región de Urabá en Antioquia.

  13. Desarrollo de la comunidad bacteriana del floc biológico de barros activados y respuesta a la desestabilización mediada por agentes externos

    OpenAIRE

    2013-01-01

    Ayarza, J. M. (2013). Desarrollo de la comunidad bacteriana del floc biológico de barros activados y respuesta a la desestabilización mediada por agentes externos (Tesis de Doctorado). Universidad Nacional de Quilmes, Bernal, Argentina. El tratamiento de efluentes basado en barros activados es el proceso más ampliamente empleado en todo el mundo para el tratamiento biológico de efluentes de origen industrial o domiciliario. El éxito del proceso radica no sólo en la selección de poblacion...

  14. Elaboración del video educativo sobre la identificación bacteriana por el método de gram

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    Medina, Jose

    2009-01-01

    El presente video fue creado y diseñado con la finalidad de proporcionar un instrumento didáctico para aprender de una manera eficaz sobre la identificación bacteriana empleando el método de tinción de Gram. La tinción de Gram es uno de los métodos más utilizados en el laboratorio bacteriológico, por lo cual es necesario llegar a un dominio adecuado de su manipulación. Este video tiene una duración de 8 minutos, durante los cuales se podrá adquirir el conocimiento suficiente para entender el ...

  15. Rhizosphere bacterial communities of potato cultivars evaluated through PCR-DGGE profiles Comunidades bacterianas associadas à rizosfera de cultivares de batata avaliadas por perfis de PCR-DGGE

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    Enderson Petrônio de Brito Ferreira

    2008-05-01

    ês períodos amostrais e cinco repetições. As amostras de rizosfera foram coletadas em três diferentes épocas durante o desenvolvimento das plantas. O DNA dos microrganismos associados à rizosfera foi extraído, amplificado por PCR com uso de iniciadores universais para bactérias e analisados por DGGE. Foram observadas alterações, relacionadas à cultivar e à idade da planta, nos perfis das comunidades bacterianas associadas à rizosfera das diferentes cultivares. As diferenças entre as comunidades bacterianas foram maiores na fase inicial do crescimento das plantas, com tendência a diminuir no estágio final de desenvolvimento. Essa variação foi detectada na comunidade bacteriana das cinco cultivares estudadas. A caracterização da microbiota do solo pode ser parte de programas de melhoramento de plantas a ser utilizada em estudos de avaliação de risco ambiental de batatas geneticamente modificadas.

  16. Controle biológico da murcha bacteriana do tomateiro, por Pseudomonas spp. fluorescentes Biological control of bacterial wilt of tomato by fluorescent Pseudomonas spp

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    Ana Rosa Peixoto

    1997-03-01

    Full Text Available Esta revisão bibliográfica teve como objetivo avaliar o potencial de antagonismo de espécies de Pseudomonas fluorescentes a Pseudomonas solanacearum, agente causal da murcha bacteriana do tomateiro. Devido a dificuldade encontrada nas estratégias utilizadas para o controle da Murcha Bacteriana por meio de métodos convencionais, alguns outros tem sido estudados, como o uso de microrganismos benéficos. As rizobactérias vem proporcionando solução viável a algumas doenças consideradas de difícil manejo. Dentre os mecanismos que tem sido sugeridos para o controle microbiano de patógenos de plantas, através do uso de rizobactérias fluorescentes, citamse produção de antibióticos, bactericinas, enzimas titicas, competição por espaço e nutrientes. Possuem uma alta capacidade de colonização e sobrevivência no hospedeiro, falares que são importantes no estabelecimento e introdução de microrganismos na rizosfera. Estas bactérias podem também incitar um aumento no desenvolvimento e na produção do hospedeiro, sendo denominadas de rizobactérias promotoras de crescimento de plantas.This literature review has the objetive of evaluating the antagonism potential of species of florescem Pseudomonas to Pseudomonas solanacearum which is the causal agent of bacterial wilt on the tomato crop. Due to serious limitation in the ejficiency of conventional methods of contrai, other strategies have been siudied, such as the use o/beneficiai microrganisms. Rhizobacteria have shown to be a viable alternative in the contrai of some diseases of difficult managmenl. Among the mechanisms which have been suggestedfor microbian control of plantpathogens with fluorescent rhizobacteria, can be used antibiotic production, bacteriocin, uric emimes and competition for colonization and survival capacity on the host. The survival capacity is very important in the introduction and stablishment ofthe microrganisms in the rhizosphere. These bacteria can aiso

  17. Características da bacteriocina produzida por Lactococcus lactis ssp. hordniae CTC 484 e seu efeito sobre Listeria monocytogenes em carne bovina

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    Bromberg,Renata; Moreno,Izildinha; Delboni,Roberta R.; Cintra,Helen C.

    2006-01-01

    O isolamento de linhagens de bactérias lácticas produtoras de bacteriocinas em carnes e seus produtos derivados resultou na detecção de Lactococcus lactis ssp. hordniae CTC 484, proveniente de frango. A bacteriocina inibiu não apenas uma outra bactéria láctica (Lactobacillus helveticus), mas também microorganismos patogênicos (Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Clostridium perfringens e Enterococcus faecalis). Ela foi inativada por causa de enzimas como: alfa-quim...

  18. Análise da microbiota bacteriana colonizadora de lesões provocadas por queimaduras nas primeiras 24 horas

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    Hamilton Aleardo Gonella

    2016-04-01

    Full Text Available Introdução: A ferida da queimadura, a princípio, é estéril. Esse período varia de 24 a 72 horas. Pela análise microbiológica, o Staphylococcus aureus é o germe mais frequentemente encontrado, seguido de Pseudomonas aeruginosa e Escherichia coli. Objetivo: Analisar qualitativamente a microbiota colonizadora das lesões por queimaduras, nas primeiras 24 horas do ocorrido, em 25 pacientes atendidos no Centro de Tratamento de Queimados (CTQ do Conjunto Hospitalar de Sorocaba (CHS. Método: Foram estudadas as amostras da margem e da área central da ferida pela técnica de coleta com uso de swab estéril. Resultados: Das 50 amostras analisadas, 15 (60% pacientes possuíam positividade para colonização de microrganismos tanto na região central quanto na margem destas. Nas amostras obtidas da região central da lesão, pudemos encontrar seis colonizadas pelo microrganismo Staphylococcus sp e oito por Staphylococcus aureus, com valores semelhantes às amostras retiradas da região marginal, com oito colonizadas pelo Staphylococcus sp e sete pelo Staphylococcus aureus. Conclusão: As lesões por queimaduras nas primeiras 24 horas são colonizadas por microrganismos. A microbiota possui correlação com o descrito na literatura consultada. A análise microbiológica precoce de queimaduras demonstra-se pertinente para a constatação de colonização e subsequente manejo para prevenção de invasão e de infecção dessas lesões, dessa forma contribuindo indiretamente para a queda na morbidade e mortalidade associada às queimaduras.

  19. Métodos de conservação de amostras de leite para determinação da contagem bacteriana total por citometria de fluxo Milk sample conservation methods to determine the total bacteria count by flow cytometry

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    Laerte Dagher Cassoli

    2010-02-01

    Full Text Available Avaliou-se o efeito da temperatura de armazenamento e da idade da amostra sobre a contagem bacteriana total de amostras de leite conservadas com azidiol para verificar a possibilidade de utilização de uma única amostra nas análises previstas na Instrução Normativa 51 (IN-51. Utilizaram-se 320 alíquotas de leite coletado de um tanque de expansão para avaliação de três temperaturas de armazenamento - a 0 ºC (congelada, 7 ºC (refrigerada e 24 ºC (à temperatura ambiente -, três tipos de conservação (bronopol, azidiol e sem conservante e quatro idades da amostra (1, 3, 5 e 7 dias. Para contagem bacteriana total, foram consideradas controle amostras refrigeradas, com azidiol e amostras de um dia e, para composição e contagem de células somáticas (CCS, os controles foram amostras refrigeradas, com bronopol e de um dia. Nas amostras conservadas com bronopol, a contagem bacteriana total foi menor que na controle, independentemente da idade e da temperatura. O mesmo foi observado nas amostras com azidiol e congeladas. Amostras com azidiol apresentaram aumento da contagem bacteriana total, independentemente da idade, enquanto, naquelas que não receberam azidiol, a contagem bacteriana total foi superior à das amostras refrigeradas, conservadas com azidiol e de um dia. As amostras conservadas com azidiol e refrigeradas tiveram aumento linear na contagem bacteriana total de 0,0058 log por dia, o que pode ser considerado sem importância prática. Amostras conservadas com azidiol e refrigeradas apresentaram CCS menor, em todas as idades, em relação a amostras refrigeradas e conservadas com bronopol. Os teores de gordura e lactose reduziram após o quinto dia. Foi necessária a coleta de duas amostras: uma destinada à determinação de CCS e da composição contendo bronopol e outra para contagem bacteriana total contendo azidiol. Amostras para contagem bacteriana total podem ser analisadas em até sete dias, se mantidas a 7 ºC e

  20. Relación entre la estructura de la comunidad bacteriana y la supresión al ahogamiento causado por Rhizoctonia solani en sustratos para plántulas de tomate

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    O. Robledo

    2010-01-01

    Full Text Available En este trabajo el objetivo fue estudiar la relación entre la supresión del ahogamiento causado por Rhizoctonia solani y la estructura de la comunidad bacteriana en sustratos orgánicos (con base en vermicomposta y composta, para el crecimiento de plántulas de tomate. Dicha estructura comunitaria se determinó mediante T-RFLP (Terminal Restriction Fragment Length Polymorphisms del gen ARNr 16S, con la enzima Hin6I. Análisis de componentes principales (PCA a partir de las abundancias relativas de los T-RFs (Fragmentos de Restricción Terminales predominantes, mostraron que los sustratos con tendencia supresiva al patógeno poseen comunidades bacterianas similares, indicando la existencia de una relación entre la estructura de la comunidad y la supresividad. Los T-RFs predominantes se relacionaron con secuencias obtenidas de una librería genómica del gen ribosomal ARNr 16S de un sustrato con tendencia supresiva. Dicho análisis de PCA reveló que entre los TRFs que contribuyen a la diferenciación de los sustratos con tendencias supresivas, se encuentran tres (64, 205 y 211 que corresponden a secuencias 16S de los siguientes géneros: Burkholderia, Duganella, Telluria, Janthinobacterium, Pseudmomonas, Stenotrophomonas y Xanthomonas. Tales géneros presentan especies con capacidad biocontroladora específica sobre el patógeno, por lo que estos resultados sugieren que los T-RFs (Hin6I 64, 205, 211 y otros, podrían ser utilizados como indicadores a priori de la capacidad supresiva de un sustrato al ahogamiento causado por Rhizoctonia solani.

  1. In vitro bacterial plaque suppression and recolonization by S. mutans and S. sobrinus Supressão e recolonização de placa bacteriana por S. mutans e S. sobrinus in vitro

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    Cássio Vicente Pereira

    2006-03-01

    que foram previamente padronizadas foram incubadas em meio de cultura contendo diferentes carboidratos fermentáveis. Em intervalos de tempo determinados, amostras de S. mutans e S. sobrinus foram coletadas a partir de culturas mistas, diluídas e semeadas em placas com meio BHI-ágar contendo rifampicina ou estreptomicina para determinação do número de células viáveis de cada espécie por contagem de unidades formadoras de colônia. Para a avaliação da colonização bacteriana e recolonização da placa bacteriana in vitro, três experimentos foram realizados: I - co-cultivo de S. mutans e S. sobrinus; II - inoculação de S. mutans em placa bacteriana pré-formada por S. sobrinus; e III - placa bacteriana pré-formada por S. mutans dispersada e plaqueada em meio BHI-ágar contendo estreptomicina ou rifampicina para determinação do número de células viáveis para cada espécie. Os resultados indicaram uma predominância de S. mutans em relação ao S. sobrinus, demonstrando a capacidade do S. mutans em inibir a formação de placa por S. sobrinus e recolonizar a superfície dentária.

  2. Caracterização da comunidade bacteriana endofítica de citros por isolamento, PCR específico e DGGE Characterization of the endophytic bacterial community from citrus by isolation, specific PCR and DGGE

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    Paulo Teixeira Lacava

    2006-04-01

    Full Text Available O objetivo deste trabalho foi caracterizar a comunidade bacteriana endofítica de plantas assintomáticas (escapes e afetadas pela clorose variegada dos citros (CVC por meio de isolamento em meio de cultura, técnica de gradiente desnaturante em gel de eletroforese (DGGE e detecção de Methylobacterium mesophilicum e Xyllela fastidiosa por meio de PCR específico, para estudar esta comunidade e sua relação com a ocorrência da CVC. A análise da comunidade bacteriana via DGGE permitiu a detecção de X. fastidiosa, bem como Klebsiella sp. e Acinetobacter sp. como endófitos de citros. Foram observados também Curtobacterium sp., Pseudomonas sp., Enterobacter sp. e Bacillus spp. Utilizando primers específicos, Methylobacterium mesophilicum e X. fastidiosa também foram observadas, reforçando hipóteses de que estas bactérias podem estar interagindo no interior da planta hospedeira.The aim of this work was to characterize endophytic bacterial community of assintomatic (escape and Citrus Variegated Chlorosis (CVC-affected citrus plants using isolation in culture medium, denaturing gradient gel electrophoresis (DGGE technique and Methylobacterium mesophilicum as well as Xylella fastidiosa specific PCR, allowing to assess this community and its interactions with CVC. The study of bacterial community by DGGE analysis allowed the detection of X. fastidiosa, as well as Klebsiella sp. e Acinetobacter sp., which were not detected previously. Curtobacterium sp., Pseudomonas sp., Enterobacter sp. and Bacillus spp. were also observed as endophyte in citrus plants. Using specific primers Methylobacterium mesophilicum and X. fastidiosa were observed, reinforcing that these bacteria could interact inside the host plant.

  3. Meningitis bacteriana Bacterial meningitis

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    Ana Teresa Alvarado Guevara

    2006-03-01

    Full Text Available En Costa Rica la meningitis bacteriana se ha convertido en un tema prioritario en lo que a vigilancia epidemiológica se refiere, en los últimos meses se ha dado un aumento en la atención pública de este tema, debido a este fenómeno se hace necesario realizar una revisión del tema. La meningitis es una inflamación de las leptomeninges y colonización del líquido cefalorraquídeo (LCR debido a diferentes agentes, lo cual produce síntomas meníngeos (Ej., cefalea, rigidez nucal, fotofobia y pleocitosis a nivel de LCR. Dependiendo de las variables se pueden agrupar en diferentes clasificaciones, tomando en cuenta el tiempo de evolución se pueden dividir en agudas o crónicas, a las primeras con pocas horas o días de inicio de la sintomatología, mientras que la crónica presenta un curso mas larvado de la enfermedad de aproximadamente 4 semanas de instauración. Existe también diferencia según su etiología, pueden ser infecciosas y no infecciosas. Causas no infecciosas incluyen: drogas antiinflamatorias, antibióticos y carcinomatosis. A su vez existe una clasificación según el agente causal. La meningitis bacteriana aguda remarca el origen bacteriano de este síndrome, el cual se caracteriza por el inicio agudo de sus síntomas y pleocitosis de predominio neutrofílico. Cada uno de los agentes bacterianos, parasíticos o fúngicos terminan por categorizar las diferentes presentaciones de este cuadro clínico (Ej., meningitis meningocóccica, meningitis criptocóccica. Es en este grupo en específico de etiología en el cual se basara el siguiente artículo. Por último pero no menos importante tenemos la meningitis aséptica, denominada de esta forma debido a una respuesta celular no pirógena causada por muchos tipos de agentes. Los pacientes muestran un inicio agudo de síntomas meníngeos, fiebre y pleocitosis pero de predominio linfocítico. Después de análisis especializados, se da pro concluido que la mayoría de los agentes

  4. Bacterial diversity of soil under eucalyptus assessed by 16S rDNA sequencing analysis Diversidade bacteriana de solo sob eucaliptos obtida por seqüenciamento do 16S rDNA

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    Érico Leandro da Silveira

    2006-10-01

    Full Text Available Studies on the impact of Eucalyptus spp. on Brazilian soils have focused on soil chemical properties and isolating interesting microbial organisms. Few studies have focused on microbial diversity and ecology in Brazil due to limited coverage of traditional cultivation and isolation methods. Molecular microbial ecology methods based on PCR amplified 16S rDNA have enriched the knowledge of soils microbial biodiversity. The objective of this work was to compare and estimate the bacterial diversity of sympatric communities within soils from two areas, a native forest (NFA and an eucalyptus arboretum (EAA. PCR primers, whose target soil metagenomic 16S rDNA were used to amplify soil DNA, were cloned using pGEM-T and sequenced to determine bacterial diversity. From the NFA soil 134 clones were analyzed, while 116 clones were analyzed from the EAA soil samples. The sequences were compared with those online at the GenBank. Phylogenetic analyses revealed differences between the soil types and high diversity in both communities. Soil from the Eucalyptus spp. arboretum was found to have a greater bacterial diversity than the soil investigated from the native forest area.Estudos sobre impacto do Eucalyptus spp. em solos brasileiros têm focalizado propriedades químicas do solo e isolamento de microrganismos de interesse. No Brasil há pouco enfoque em ecologia e diversidade microbiana, devido às limitações dos métodos tradicionais de cultivo e isolamento. A utilização de métodos moleculares no estudo da ecologia microbiana baseados na amplificação por PCR do 16S rDNA têm enriquecido o conhecimento da biodiversidade microbiana dos solos. O objetivo deste trabalho foi comparar e estimar a diversidade bacteriana de comunidades simpátricas em solos de duas áreas: uma floresta nativa (NFA e outra adjacente com arboreto de eucaliptos (EAA. Oligonucleotídeos iniciadores foram utilizados para amplificar o 16S rDNA metagenômico do solo, o qual foi

  5. Estudo dos parâmetros da ultrafiltração de permeado de soro de queijo fermentado por Lactococcus lactis subsp. lactis Ultrafiltration conditions of whey permeate fermented by Lactococcus lactis subsp. lactis

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    Viviane BRONSTEIN

    1998-04-01

    Full Text Available Permeado de soro doce, suplementado com extrato de levedura e peptona, foi utilizado como meio de crescimento para Lactococcus lactis subsp. lactis. No final da fase exponencial de crescimento, o meio de cultura fermentado foi submetido a uma ultrafiltração com o objetivo de concentrar o microrganismo. Foram realizados 6 processamentos diferentes, nos quais variou-se as condições iniciais da ultrafiltração, tendo sido avaliados os seguintes parâmetros: porosidade da membrana, pH e número de células viáveis no permeado e no retentado, a fim de ser estudado a influência de cada parâmetro na taxa de permeação da ultrafiltração. As membranas utilizadas foram eficazes como meio de barragem para o microrganismo Lactococcus lactis subsp. lactis, ficando o retentado com uma média celular de 10(8 ufc/ml e o permeado com uma média celular de 10² ufc/ml. Membranas de diferentes porosidades tiveram taxas de fluxo semelhantes. O aumento da concentração celular provocou a diminuição do fluxo. O pH também influenciou a taxa de permeação, havendo um aumento do fluxo quando foi utilizado um pH inicial mais alto.Cheese whey permeate supplemented with yeast extract and peptone was used as a growth medium for the bacteria Lactococcus lactis subsp. lactis. At the end of the exponential growth phase, the fermented growth medium was ultrafiltered to concentrate the microorganism and to evaluate the effect of the membrane porosity, inicial UF pH and cellular concentration in permeation rate during the ultrafiltration process. The membranes used were efficient as a mean of a barrage for the Lactococcus lactis subsp. lactis. On average, the cellular concentrations were 10(8 CFU/mL and 10² CFU/mL for retentate and permeate, respectively. Membranes of different porosities had very similar flux rates. Better flow rates were obtained with inicial UF pH 6,5 and with the minors micrrorganism concentration.

  6. Incidência de murcha-bacteriana em tomate para processamento industrial sob irrigação por gotejamento e aspersão Incidence of bacterial wilt on processing tomato under drip and sprinkle irrigation

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    Waldir A. Marouelli

    2005-06-01

    Full Text Available O estudo foi realizado na Embrapa Hortaliças, Brasília (DF, com o objetivo de avaliar a incidência de murcha-bacteriana em tomateiro para processamento industrial irrigado por gotejamento e por aspersão, cultivado em solo naturalmente infestado com a raça 1, biovar I de Ralstonia solanacearum, nas condições edafoclimáticas do Cerrado brasileiro. Para gotejamento foram também avaliados os regimes hídricos com turnos de rega de 0,5; 1; 2; 4 e 8 dias. A irrigação por gotejamento favoreceu significativamente a ocorrência da doença, apresentando em média, aos 65 dias após o transplante de mudas, 42,5% de plantas com sintoma contra 5% de casos ocorridos na irrigação por aspersão. A incidência da doença no gotejamento não foi afetada (p>0,05 pelo regime hídrico adotado.A field experiment was carried out at Embrapa Hortaliças, Brasilia, Brazil, with the objective of assessing the incidence of bacterial wilt on processing tomatoes irrigated by drip and sprinkle systems, under soil and climate conditions of the Brazilian "Cerrado". The trial was performed in a field naturally infested with race 1, biovar I of Ralstonia solanacearum. Different irrigation frequencies (0.5; 1; 2; 4; and 8 days were further evaluated for drip irrigation. Disease incidence was significantly higher when the crop was drip irrigated, with an average of 42.5% of wilted plants in comparison with 5.0% incidence for sprinkle irrigation, 65 days after transplanting. Frequencies of drip irrigation did not affect (p>0.05 bacterial wilt incidence.

  7. Acute bacterial meningitis caused by Streptococcus pneumoniae resistant to the antimicrobian agents and their serotypes Meningite bacteriana aguda por Streptococcus pneumoniae resistente aos antimicrobianos e seus sorotipos

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    Andrea Maciel de Oliveira Rossoni

    2008-09-01

    prévio de antibiótico (p=0,046. As taxas de resistência encontradas, moderada a penicilina, baixa para cefalosporina e nula para vancomicina, sugerem como terapêutica empírica inicial para tratamento da meningite bacteriana aguda de origem comunitária, a cefalosporina de terceira geração isoladamente.

  8. Neumonía bacteriana con desarrollo de abscesos pulmonares secundarios a infección causa por Streptococcus intermedius proveniente de absceso dental

    OpenAIRE

    Álvarez Herrera, Leonardo

    2013-01-01

    A  continuación  se  presenta  el  caso  de  un  paciente  masculino  de  29  años,  con  los  únicos  antecedentes personales patológicos de psoriasis y asma bronquial, el cual desarrolló neumonía con múltiples abscesos pulmonares bilaterales causados por  labacteria Streptococcus  intermedius proveniente de un absceso dental.  El  paciente  requirió  internamiento  hospitalario    por  un  lapso  de  17  días  y  recibió  tratamiento  con Ampicilina/Sulbactam 1,5 gramos  cada 6 horas intrav...

  9. Efecto de los fructooligosacáridos en la población bacteriana fecal de un neonato, crecida en cultivo por lote

    OpenAIRE

    Patricia Martínez C.; Lino Mayorga R.; Teresa Ponce N.; Alejandro Roldán J.; Esteban Barranco F.; Rina González C.; Alejandro Azaola E.

    2008-01-01

    el intestino humano alberga aproximadamente 1014 bacterias. Algunos de estos grupos de bacterias son conocidas como benéficas o probióticas tales como: lactobacilos y bifidobacterias, por lo que se ha propuesto el consumo de suplementos alimenticios que estimulen a estos grupos. En este estudio se realizaron fermentaciones anaerobias y microaerobias en lote, utilizando glucosa y fructooligosacáridos (FOS) como sustrato, con el fin de conocer su efecto sobre la microbiota intestinal. Se cuanti...

  10. Otimização da produção de nata (celulose bacteriana por fermentação em superfície

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    DANESI Eliane Dalva Godoy

    1998-01-01

    Full Text Available A nata de coco, alimento glicídico obtido por fermentação em superfície promovida por Acetobacter xylinum, é bastante difundida em alguns países asiáticos, principalmente nas Filipinas. Como meio de cultivo são utilizadas a água ou o leite de coco, produtos de baixo valor econômico e resíduos de processamento da fruta; há indicativos na literatura, entretanto, de que outros resíduos agro-industriais como soro de leite ou mesmo suco de frutas podem ser utilizados. A fim de avaliar a produção de nata para posteriores estudos visando o uso de meios alternativos, foi utilizado um meio de composição definida com o qual foi possível definir as condições de pH, de inóculo e de incubação, assim como observar a influência de açúcares e de ácidos no processo. Foram delineados experimentos usando-se ácido acético e glucose como variáveis de entrada visando a otimização do processo. As condições de fermentação incluíram correção do pH para 4, adição de 10% (v/v de inóculo ao meio e incubação a 28°C por 10 dias. As condições encontradas como ótimas em relação às concentrações iniciais dos nutrientes considerados foram 0,65 moles/l de ácido acético e 67,4 g/l de glucose, com o que se produz 7,107 g de nata por 250 ml de meio .

  11. Biofertilizantes no controle da mancha bacteriana (Xanthomonas spp. do tomateiro

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    Vinícius William Borges Rodrigues

    2016-03-01

    Full Text Available RESUMO A mancha bacteriana do tomateiro, causada por quatro espécies de Xanthomonas pode provocar perdas significativas na produção da cultura e a utilização de biofertilizantes na proteção de plantas tende a reduzir a incidência de doenças. O objetivo do trabalho foi avaliar o efeito dos biofertilizantes no controle preventivo e curativo da mancha bacteriana do tomateiro. Para o controle preventivo da doença, plantas de tomate cultivar Santa Cruz Kada, com 3 a 4 folhas foram pulverizadas com os biofertilizantes (Soil-Set, Agro-Mos e Cop-R-Quick e água (testemunha; e dois dias após foram inoculadas por aspersão com a suspensão bacteriana nas concentrações 109 UFC mL-1 (OD550=0,5 e 106UFC mL-1, com o isolado UFU A35 de Xanthomonas sp. Para o controle curativo, as plantas foram inoculadas com a suspensão bacteriana, e dois dias após foram pulverizadas com os biofertilizantes e água. A severidade da mancha bacteriana foi avaliada usando uma escala diagramática; aos 3, 5, 8, 11 e 14 dias após a inoculação e calculada a área abaixo da curva de progresso de doença (AACPD. O controle preventivo foi mais eficiente no manejo da mancha bacteriana do tomateiro, e os diferentes biofertilizantes reduziram a severidade da doença.

  12. Características da bacteriocina produzida por Lactococcus lactis ssp. hordniae CTC 484 e seu efeito sobre Listeria monocytogenes em carne bovina Characterisation of the bacteriocin produced by Lactococcus lactis ssp. hordniae CTC 484 and the effect of this compound on Listeria monocytogenes in beef

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    Renata Bromberg

    2006-03-01

    Full Text Available O isolamento de linhagens de bactérias lácticas produtoras de bacteriocinas em carnes e seus produtos derivados resultou na detecção de Lactococcus lactis ssp. hordniae CTC 484, proveniente de frango. A bacteriocina inibiu não apenas uma outra bactéria láctica (Lactobacillus helveticus, mas também microorganismos patogênicos (Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Clostridium perfringens e Enterococcus faecalis. Ela foi inativada por causa de enzimas como: alfa-quimotripsina, tripsina, pronase E, ficina, pepsina, papaína e lipase. Além disso, a bacteriocina mostrou-se termoestável, mesmo a temperaturas de autoclavagem (121°C/10 min e foi produzida em condições de armazenamento sob refrigeração. A bacteriocina mostrou-se ativa dentro de uma ampla faixa de valores de pH (2-10, porém a maior atividade ocorreu em valores menores de pH. A eficiência da linhagem CTC 484, assim como a de sua bacteriocina na redução e inibição do crescimento de Listeria monocytogenes em carne bovina estéril, foram avaliadas. Os resultados indicaram que o tratamento da carne por meio da inoculação desta bactéria contribuiu para o aumento da segurança e extensão da vida útil deste alimento.Screening for the bacteriocin production of strains of lactic acid bacteria from various meat and meat products resulted in the detection of a bacteriocin-producing Lactococcus lactis ssp. hordniae CTC 484, isolated from chicken. The bacteriocin inhibited not only closely related lactic acid bacterium (Lactobacillus helveticus, but also pathogenic microorganisms (Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Clostridium perfringens, and Enterococcus faecalis. This compound was inactivated by alpha-chymotrypsin, trypsin, pronase E, ficin, pepsin, papain, and also by lipase. It was heat stable even at autoclaving temperature (121°C/10 min and was produced under refrigerated storage. It was also active over a wide

  13. Las enfermedades periodontales como infecciones bacterianas

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    A. Bascones Martínez

    Full Text Available Las infecciones periodontales son un conjunto de enfermedades localizadas en las encías y estructuras de soporte del diente. Están producidas por ciertas bacterias provenientes de la placa bacteriana. Estas bacterias son esenciales para el inicio de la enfermedad, pero existen factores predisponentes del hospedador y microbianos que influyen en la patogénesis de la enfermedad. La microbiota bacteriana periodontopatógena es necesaria pero no suficiente para que exista enfermedad, siendo necesaria la presencia de un hospedador susceptible. Estas enfermedades se han clasificado en gingivitis, limitadas a las encías y periodontitis, extendidas a tejidos más profundos. La clasificación de las enfermedades periodontales ha ido variando a lo largo de los años y es en el International Workshop for a Clasification of Periodontal Diseases and Conditions, en 1999, cuando se aprueba la clasificación que se expone en este trabajo. En él, se hace una revisión global de los diferentes cuadros de las enfermedades periodontales. Posteriormente, se propone el empleo de antibioterapia de utilización sistémica como la amoxicilina, amoxicilina-clavulánico y metronidazol como primera opción de tratamiento coadyuvante de estas enfermedades.

  14. Las enfermedades periodontales como infecciones bacterianas Periodontal diseases as bacterial infection

    OpenAIRE

    2005-01-01

    Las infecciones periodontales son un conjunto de enfermedades localizadas en las encías y estructuras de soporte del diente. Están producidas por ciertas bacterias provenientes de la placa bacteriana. Estas bacterias son esenciales para el inicio de la enfermedad, pero existen factores predisponentes del hospedador y microbianos que influyen en la patogénesis de la enfermedad. La microbiota bacteriana periodontopatógena es necesaria pero no suficiente para que exista enfermedad, siendo necesa...

  15. Efectividad del uso empírico de vancomicina para tratar la meningitis bacteriana aguda por Streptococcus pneumoniae. Revisión sistemática de la literatura y metaanálisis.

    OpenAIRE

    Galeano Tapias, Adriana Catalina; Piedrahita Vargas, Cristian Alfonso

    2015-01-01

    Introducción. Debido al aumento de la frecuencia de Streptococcus pneumoniae resistente a penicilina en meningitis bacteriana aguda y de los casos de fracaso al tratamiento con betalactámicos, se recomienda el uso combinado de vancomicina con cefalosporinas de tercera generación como primera línea de tratamiento empírico. Sin embargo, la efectividad de dicho régimen y su relación con la resistencia antibiótica no se conoce con claridad. Objetivo. Evaluar la efectividad de la administración em...

  16. Producción de ácido láctico por una mezcla de Lactococcus lactis y Streptococcus salivarius en fermentaciones en discontinuo Lactic acid production from a mixture of cultures of Lactococcus lactis and Streptococcus salivarius using batch fermentation

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    Rodríguez de Stouvenel Aida

    2005-07-01

    Full Text Available Se estudió la producción de ácido láctico (AL, la conversión de sustrato (CG, y el rendimiento(Yp/s de Lactococcus lactis, Streptococcus salivarius y una mezcla 1:1 de ambas cepas en sustrato glucosado. Lactococcus lactis se seleccionó de 20 cepas homofermentativas aisladas de cultivos de caña de azúcar variedad CC85-92 y Streptococcus salivarius se aisló de un fermento láctico comercial. En fermentaciones llevadas a cabo con la mezcla microbiana, a 32 °C con 60 gL-1 de glucosa y pH 6,0 se obtuvo un máximo de 47,63 gL-1 de ácido láctico, conversión de glucosa de 95,4% y rendimiento en producto de 0,83 gg-1. Palabras clave: caña de azúcar, Lactococcus lactis, Streptococcus salivarius, mezcla de cepas.Production of lactic acid (LA, yield (Yp/s and substrate conversion (SC from Lactococcus lactis, Streptococcus salivarius and their mixtures were tested. Lactococcus lactis was selected from 20 homofermentative strains isolated from a sugar cane crop (variety CC85-92 and Streptococcus salivarius was isolated from a commercial lactic ferment. Batch fermentation experiments at 32 C with a glucose concentration of 60 gL-1 and a pH of 6,0 were carried out. A maximum of 47,63 gL-1 of lactic acid concentration, 95,4% of substrate conversion and 83 gg-1 were obtained from the mixture of strains after a fermentation of 48 h. Key words: sugar cane, Lactococcus lactis, Streptococcus salivarius, mixture of strains.

  17. Lactococcus lactis productor de bacteriocina utilizable como cultivo iniciador para acelerar la maduración de queso

    OpenAIRE

    Martínez-Cuesta, M. Carmen; Requena, Teresa; Peláez, Carmen

    2003-01-01

    Lactococcus lactis productor de bacteriocina utilizable como cultivo iniciador para acelerar la maduración de queso. La presente invención describe un procedimiento de producción de transconjugantes de Lactococcus lactis (se describe en detalle el Lactococcus lactis CECT5367) productores de bacteriocina y por tanto inmune a ella. Este microorganismo y otros similares pueden utilizarse como cultivos iniciadores para la elaboración de queso semiduro produciendo quesos de buena calidad organolép...

  18. Antibióticos vs. resistencia bacteriana

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    Elso Manuel Cruz Cruz

    2015-02-01

    Full Text Available La resistencia bacteriana a los antibióticos es un problema de salud mundial que se encuentra en constante evolución. De manera frecuente se reportan nuevos mecanismos de resistencia bacteriana a los antibióticos, tanto en bacterias gram negativas como en gram positivas. La presencia de resistencia en una bacteria causante de infección disminuye las posibilidades de obtener la curación clínica y la erradicación bacteriológica e incrementa los costos del tratamiento, la morbilidad y la mortalidad; por lo que es importante seleccionar el tratamiento adecuado. Uno de los aspectos que más preocupa a los médicos en el diagnóstico y tratamiento de una infección es la llamada resistencia adquirida, la cual ocurre en una bacteria inicialmente sensible a los antibióticos, por cambios, mutaciones o la adquisición de genes de resistencia durante el fenómeno de transferencia genética lateral, proceso por medio del cual un organismo transfiere material genético a otra célula que no es descendiente. La resistencia bacteriana adquirida a los antibióticos puede ser de distintos tipos, dependiendo de la presión selectiva, las mutaciones o la transferencia de genes de resistencia. Las definiciones de resistencia se clasifican según el número y clase de antibióticos afectados. La multirresistencia (Multiple Drug Resistance, MDR se define como la ausencia de sensibilidad a, por lo menos, un fármaco en tres o más de las categorías de antibióticos; la resistencia extrema (Extensively Drug-Resistant, XDR se refiere a la ausencia de sensibilidad a, por lo menos, un agente en todas las categorías de antimicrobianos, excepto en dos de ellas o menos, y la resistencia a todos los antimicrobianos se define como resistencia a todas las categorías de antibióticos. (1 Los mecanismos de resistencia dependen del tipo de bacteria que los desarrollen. Las bacterias gram positivas que producen con más frecuencias infecciones en humanos y que por

  19. A orbifloxacina no tratamento das cistites bacterianas em gatos domésticos

    OpenAIRE

    Reche Junior Archivaldo

    2005-01-01

    O presente estudo teve como objetivos, avaliar o uso da orbifloxacina nas cistites bacterianas de felinos, e seus possíveis efeitos colaterais, mormente a nefro e/ou hepatotoxicidade. Para tanto, foram colhidas amostras de urina de 53 gatos com históricos variados, mas com predisposição à infecção urinária. A cistite bacteriana foi comprovada, através de exame microbiológico, em 13 pacientes. No entanto, apenas 10 apresentaram infecção por agentes sensíveis a orbifloxacina. Esses 10 pacientes...

  20. Cambios en el espectro de la meningitis bacteriana espontánea en el paciente adulto en un hospital de tercer nivel

    OpenAIRE

    Pomar Solchaga, Virginia

    2014-01-01

    La tesis titulada "Cambios en el espectro de la meningitis bacteriana espontánea en el paciente adulto en un hospital de tercer nivel" está formada por 3 artículos y tiene como objetivo global analizar los cambios observados en las meningitis bacterianas del adulto en las últimas décadas en un hospital de tercer nivel de Barcelona. En el primer artículo, se evalúan 635 meningitis bacterianas desde 1982 al 2010, y se analizan en 2 períodos: 1982-1995 y 1996-2010. En el segundo periodo la pobla...

  1. Diversidade e estrutura da comunidade bacteriana associada às armadilhas da planta carnívora Utricularia gibba (Lentibulariaceae) e ao ambiente aquático.

    OpenAIRE

    Almir José Ferreira

    2011-01-01

    A diversidade microbiana em ambientes aquáticos e sua associação com plantas carnívoras ainda é pouco estudada. Assim, a comunidade bacteriana da planta carnívora Utricularia gibba e do seu meio aquático foi avaliada por meio do seqüenciamento em larga escala (454 Roche) de uma biblioteca do gene 16S rRNA. Os resultados indicaram que a comunidade bacteriana na água é significativamente diferente da comunidade dos utrículos. Além disso, a comunidade bacteriana da água é composta principalmente...

  2. HELICOBACTER PYLORI EN LA FLORA BACTERIANA ORAL

    OpenAIRE

    Moromi Nakata, Hilda; Departamento Académico Ciencias Básicas Estomatológicas. Facultad de Odontología. UNMSM.

    2014-01-01

    No hay duda de la relación existente entre enfermedades orales con otras enfermedades sistémicas. En tal contexto, las bacterias de la flora bacteriana oral, que alcanzan alrededor de 350 especies, para la mayoría de tales bacterias no se ha demostrado un rol específico, conociéndose sí una clara relación entre los Estreptococos orales (Streptococcus sanguis, Strecoccus mutans, Streptococcus sobri nus) y Actinobacillus actinomycetencomitans, entre otros, con la endocarditis bacteriana; así co...

  3. Antibióticos vs. resistencia bacteriana

    OpenAIRE

    Elso Manuel Cruz Cruz

    2015-01-01

    La resistencia bacteriana a los antibióticos es un problema de salud mundial que se encuentra en constante evolución. De manera frecuente se reportan nuevos mecanismos de resistencia bacteriana a los antibióticos, tanto en bacterias gram negativas como en gram positivas. La presencia de resistencia en una bacteria causante de infección disminuye las posibilidades de obtener la curación clínica y la erradicación bacteriológica e incrementa los costos del tratamiento, la morbilidad y la mortali...

  4. Lysozyme expression in Lactococcus lactis

    NARCIS (Netherlands)

    Guchte, Maarten van de; Wal, Fimme Jan van der; Kok, Jan; Venema, Gerhardus

    1992-01-01

    Three lysozyme-encoding genes, one of eukaryotic and two of prokaryotic origin, were expressed in Lactococcus lactis subsp. lactis. Hen egg white lysozyme (HEL) could be detected in L. lactis lysates by Western blotting. No lysozyme activity was observed, however, presumably because of the absence o

  5. Tratamento ambulatorial da endocardite bacteriana estreptocócica Tratamiento clínico de la endocarditis bacteriana estreptocócica Ambulatory treatment of streptococcal bacterial endocarditis

    Directory of Open Access Journals (Sweden)

    Sirio Hassem Sobrinho

    2010-04-01

    Full Text Available A endocardite bacteriana é uma grave doença infecciosa cujo tratamento é tradicionalmente feito com o paciente internado. recebendo medicação intravenosa. A possibilidade de tratamento domiciliar ou ambulatorial. em casos estritamente selecionados. é atraente tanto do ponto de vista social quanto do econômico. Apresentamos o relato de 6 pacientes com diagnóstico de endocardite bacteriana por Streptococcus. tratados parcial ou integralmente em regime ambulatorial. Todos evoluíram sem complicações e com resolução completa do quadro infeccioso.La endocarditis bacteriana es una severa enfermedad infecciosa cuyo tratamiento se hace tradicionalmente con el paciente internado, recibiendo medicación intravenosa. La posibilidad de tratamiento domiciliar o clínico, en casos estrictamente seleccionados, es atractivo desde el punto de vista social como del económico. Presentamos el caso clínico de 6 pacientes con diagnóstico de endocarditis bacteriana por streptococcus, tratados parcial o integralmente en régimen ambulatorio. Todos evolucionaron sin complicaciones y con resolución completa del cuadro infeccioso.Bacterial endocarditis is a severe infectious disease. of which treatment is traditionally carried out in hospitalized patients through intravenous medication. The possibility of at-home or ambulatory treatment. for stringently selected cases. is attractive from the social as well as from the economic point of view. We report 6 patients with a diagnosis of bacterial endocarditis caused by Streptococcus. treated partially or completely on an outpatient basis. All of them evolved without complications and presented complete resolution of the infection.

  6. Oftalmoplegia internuclear achado clínico inicial e único em endocardite bacteriana

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    Antonio L. dos Santos Werneck

    1990-03-01

    Full Text Available Oftalmoplegia internuclear unilateral traduz-se por paralisia homolateral da adução ocular e nistagmo contralateral. As principais causas são a esclerose múltipla e a insuficiência vértebro-basilar. Apresentamos um caso secundário a endocardite bacteriana, em que este sinal iniciou o quadro e foi o único achado neurológico.

  7. Peritonite bacteriana espontânea

    Directory of Open Access Journals (Sweden)

    Strauss Edna

    2003-01-01

    Full Text Available A peritonite bacteriana espontânea ocorre em 30% dos cirróticos com ascite e, neste grupo, apresenta altas taxas de morbidade e mortalidade. Os fatores predisponentes incluem a diminuição da defesa imunológica encontrada no homem nas fases avançadas da cirrose, o supercrescimento da flora intestinal e a translocação bacteriana da luz dos intestinos aos linfonodos mesentéricos. As manifestações clínicas variam de graves a leves ou ausentes, sendo sempre necessária a análise do líquido ascítico. O diagnóstico de peritonite bacteriana espontânea se faz pela contagem de neutrófilos > 250/mm³ no líquido ascítico associado ou não ao crescimento de bactéria na cultura. As enterobactérias predominam como causa da infecção, sendo a Echerichia coli a bactéria mais freqüentemente isolada. O diagnóstico precoce e o tratamento adequado provocaram a queda das taxas de mortalidade nas duas últimas décadas. O uso endovenoso de cefalosporinas de terceira geração mostra-se eficaz em 70% a 95% dos casos. A recorrência de peritonite bacteriana espontânea é comum e pode ser prevenida com norfloxacina oral, de uso contínuo. O surgimento de resistência bacteriana tem estimulado a procura de novas opções para a profilaxia da peritonite bacteriana espontânea; os probióticos constituem nova abordagem promissora, mas que necessita melhor avaliação. Recomenda-se a profilaxia primária de curta duração aos cirróticos com ascite que apresentem episódio de hemorragia digestiva alta.

  8. Resistencia bacteriana en El Salvador

    OpenAIRE

    Vásquez Hidalgo, Antonio

    1999-01-01

    Objetivo. Determinar la eficacia de los antibióticos de uso común en el tratamiento de las enfermedades Infecciosas. El estudio tiene como propósito investigar ¿Cuál es la eficacia clínica de los antibióticos determinado por pruebas de sensibilidad in vitro y aplicados in vivo en los pacientes adultos que consultan por enfermedades infecciosas, en una clínica asistencial en Soyapango, durante el período de Julio a Diciembre de 1997-1998?. Método. Se utilizó un diseño híbrido cuasiexperimental...

  9. Pneumonia bacteriana adquirida na comunidade

    OpenAIRE

    Machado, Lais Del Prá Netto

    2015-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde, Programa de Pós-Graduação em Farmácia, Florianópolis, 2015. A pneumonia pode ser causada por diversos microrganismos e classificada de forma abrangente, havendo poucos e frágeis estudos clínicos e epidemiológicos sobre pneumonias adquiridas na comunidade (PACs). Os patógenos mais frequentes nas PACs são Streptococcus pneumoniae e Haemophilus influenzae (em pneumonias típicas) e Mycoplasma pneumoni...

  10. Microbiota bacteriana da conjuntiva no pré-operatório de injeção intravítrea de antiangiogênico por degeneração macular relacionada à idade comparada com a de cirurgia de catarata Preoperative conjunctival bacterial microbiota of antiangiogenic intravitreous injection for age-related macular degeneration compared to cataract surgery preoperative microbiota

    Directory of Open Access Journals (Sweden)

    José Ricardo Diniz

    2010-06-01

    Full Text Available Objetivo: Avaliar a microbiota bacteriana da conjuntiva e perfil de antibiograma no pré-operatório de injeção intravítrea de antiangiogênico por degeneração macular relacionada à idade, comparando com a de pacientes no pré-operatório de cirurgia de catarata. Métodos: Realizou-se estudo transversal, observacional, tipo série de casos. Foram constituídos dois grupos: grupo I (degeneração macular com 26 olhos de 26 pacientes (12 homens/14 mulheres com média de idades de 69,2 ± 11,5 anos; grupo II (catarata com 27 olhos de 27 pacientes (9 homens/18 mulheres com média de idades de 67,6 ± 7,9 anos. Os grupos foram homogêneos em relação à idade (p=0,538 e ao sexo (p=0,787. Foi realizada coleta de secreção do fundo de saco inferior da conjuntiva, através de "swab", e imediatamente colocado em tubo contendo meio líquido BHI ("brain heart infusion". As amostras foram processadas conforme técnicas laboratoriais padrão e realizado antibiograma de cada colônia isolada. Resultados: Houve crescimento de 26 colônias bacterianas no grupo I, com 2 olhos não apresentando crescimento e 30 colônias no grupo II. Houve maior frequência de bactérias Gram positivas nos dois grupos: 23/26 colônias (88,4% no grupo I e 29/30 colônias (96,7% no grupo II, com predomínio de Staphylococcus aureus em ambos os grupos, com 16 amostras (61,5% e 17 (56,7%, respectivamente. Staphylococcus coagulase negativa foi a segunda bactéria mais identificada, com 19,2% no grupo I e 20,0% no grupo II. Nenhuma diferença de frequência entre os grupos alcançou significância estatística. Não foi observada diferença estatisticamente significante nas sensibilidades das bactérias aos antibióticos testados entre os dois grupos. Conclusões: Não houve diferença na distribuição das bactérias e no perfil de antibiograma da microbiota conjuntival de pacientes no pré-operatório de injeção intravítrea por degeneração macular, comparada a de

  11. Estudo da incidência de vaginose bacteriana em parturientes pré-termo ou gestantes com amniorrexe prematura

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    Raquel G. A. Torres

    2008-01-01

    Full Text Available Objetivos: relacionar a incidência de vaginose bacteriana entre parturientes com diagnóstico de trabalho de parto prematuro ou gestantes com amniorexe prematura em Sorocaba/SP. Metodologia: estudamos, de setembro/2003 a junho/2004, 30 pacientes internadas com diagnóstico clínico de trabalho de parto prematuro e/ou amniorexe prematura com idade gestacional inferior a 37 semanas. Como grupo controle tivemos 30 gestantes internadas para tratamento de outras intercorrências clínicas e/ou obstétricas, pareadas com o grupo de estudo pela idade cronológica e idade gestacional. A vaginose bacteriana foi diagnosticada pelo pH vaginal superior a 4.5, liberação de odor de “peixe podre” ao adicionar KOH (10% ao conteúdo vaginal, presença de “clue-cell” nesse material, e a caracterização de esfregaço sugestivo de vaginose bacteriana pelo método de Gram. Resultados: a vaginose bacteriana foi encontrada em 10.0% das pacientes do grupo de estudo e em 13.3% das pacientes do grupo controle. Encontramos também a presença de processos infecciosos vaginais, especialmente causados por leveduras, ambos achados não apresentaram significância estatística. Conclusão: a vaginose bacteriana não se associou de maneira significante com a ocorrência de trabalho de parto prematuro e/ou amniorexe prematura. Trabalho subsidiado por bolsa PIBIC-CNPq.

  12. VULVOVAGINITIS BACTERIANA EN LA PREPÚBER

    OpenAIRE

    Barbosa R.,Gabriel; Sánchez D.,Paola

    2005-01-01

    Considerando la alta incidencia de vulvovaginitis en la consulta de ginecología pediátrica y de adolescentes, y los aspectos únicos de la microbiología y endocrinología de la paciente prepúber se presenta una revisión de la literatura con lo más relevante de los últimos 5 años, en lo que se refiere a epidemiología, etiología, diagnóstico y tratamiento de la vulvovaginitis bacteriana específica de la niña prepúber. No existe claridad acerca de la microflora vaginal normal, lo cual dificulta en...

  13. A orbifloxacina no tratamento das cistites bacterianas em gatos domésticos The orbifloxacin in the treatment of lower urinary tract infections in cats

    OpenAIRE

    Archivaldo Reche Junior

    2005-01-01

    O presente estudo teve como objetivos, avaliar o uso da orbifloxacina nas cistites bacterianas de felinos, e seus possíveis efeitos colaterais, mormente a nefro e/ou hepatotoxicidade. Para tanto, foram colhidas amostras de urina de 53 gatos com históricos variados, mas com predisposição à infecção urinária. A cistite bacteriana foi comprovada, através de exame microbiológico, em 13 pacientes. No entanto, apenas 10 apresentaram infecção por agentes sensíveis a orbifloxacina. Esses 10 pacientes...

  14. Efeito e modo de ação das bacteriocinas produzidas por Lactococcus lactis subsp. lactis ITAL 383, ATCC 11454 e CNRZ 150 contra Listeria innocua LIN 11 Effect and mode of action of the bacterioncin produced by Lactococcus. lactis subsp. lactis ITAL 383, ATCC 11454 e CNRZ 150 against Listeria innocua LIN 11

    Directory of Open Access Journals (Sweden)

    Izildinha MORENO

    1999-01-01

    Full Text Available O efeito e o modo de ação das bacteriocinas produzidas por L. lactis subsp. lactis ITAL 383 e CNRZ 150 são similares à nisina de L. lactis subsp. lactis ATCC 11454. Estas bacteriocinas apresentaram um modo de ação bactericida, causando a lise de células de L. innocua LIN 11, associada ao decréscimo da absorbância e da viabilidade celular. O efeito letal foi maior para células em fase exponencial comparativamente à fase estacionária de crescimento. A adsorção dessas bacteriocinas às células de L. innocua LIN 11 foi muito rápida e influenciada pelo pH do meio de suspensão; adsorção máxima foi verificada a pH 6,0 e logo após o contato inicial. Perda completa de adsorção ocorreu em pH 2,0.The effect and mode of action of the bacteriocin produced by L. lactis subsp. lactis ITAL 383 and CNRZ 150 are similar to the nisin produced by L. lactis subsp. lactis ATCC 11454. It was clearly bactericidal, and caused lysis of a strain of L. innocua LIN 11 detected by the decrease of absorbance values and the cell viability. Their lethal effect was considerably higher during the logarithmic growth when compared to the stationary phase. Adsorption developed rapidly and was influenced by the pH value of the suspension medium. Maximum adsorption was observed at pH 6,0 and immediately after initial contact and loss at pH 2,0.

  15. The Lactococcus lactis Thioredoxin System

    DEFF Research Database (Denmark)

    Efler, Petr

    -dependent thioredoxin reductase (NTR) in order to complete its catalytic cycle. Glutathione-dependent glutaredoxin complements Trx in many organisms. This thesis focuses on disulfide reduction pathways in Lactococcus lactis, an important industrial microorganism used traditionally for cheese and buttermilk production...... ribonucleotide reductase (NrdEF). Physiological functions of LlTrxA and LlTrxD were studied using ΔtrxA, ΔtrxD and ΔtrxAΔtrxD mutant strains of L. lactis ssp. cremoris MG1363 exposed to various stress conditions and comparing them to the wild type (wt) strain. These experiments revealed that the ΔtrxA genotype...... with a previous study showing that NTR in L. lactis is not essential. Therefore, the presence of an additional thiol redox system is hypothesized. Biochemical studies demonstrated that recombinant LlTrxA, LlTrxD and LlNrdH are substrates for LlNTR, while only LlTrxA and LlNrdH are efficiently reduced by E. coli...

  16. A orbifloxacina no tratamento das cistites bacterianas em gatos domésticos

    Directory of Open Access Journals (Sweden)

    Reche Junior Archivaldo

    2005-01-01

    Full Text Available O presente estudo teve como objetivos, avaliar o uso da orbifloxacina nas cistites bacterianas de felinos, e seus possíveis efeitos colaterais, mormente a nefro e/ou hepatotoxicidade. Para tanto, foram colhidas amostras de urina de 53 gatos com históricos variados, mas com predisposição à infecção urinária. A cistite bacteriana foi comprovada, através de exame microbiológico, em 13 pacientes. No entanto, apenas 10 apresentaram infecção por agentes sensíveis a orbifloxacina. Esses 10 pacientes foram então submetidos ao tratamento com orbifloxacina na dose de 2,5mg kg-1 a cada 24 horas por 10 dias. Não houve crescimento bacteriano nas amostras de urina submetidas à cultura, 72 horas após a interrupção do tratamento. Não foram observados sinais de nefro e/ou hepatotoxicidade nesses pacientes, uma vez que os níveis séricos de alanina aminotransferase (ALT, aspartato aminotransferase (AST, fosfatase alcalina (FA, albumina, uréia e creatinina não tiveram variação significativa após o uso do fármaco. Portanto, os resultados apresentados sugerem que a orbifloxacina pode ser usada como agente antimicrobiano nas infecções urinárias de felinos.

  17. Adhesión bacteriana a biomateriales Bacterial adhesion to biomaterials

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    C Ábalos

    2005-02-01

    Full Text Available En términos generales, para la adhesión bacteriana, influyen cuatro elementos: Material, Microorganismos, antimicrobianos y mecanismos de defensa. La influencia del material es más importante en los estadios iniciales de la adhesión, pudiendo influir el mismo material, su rugosidad o su energía superficial., si es que existe una influencia del material en la adhesión bacteriana, esta reside en las caracteristicas de la película adquirida y en la especificidad de las proteinas adsorbidas salivares (receptores, que puedan ser condicionadas por la composición del material o por las características de superficie de este.In general terms, there are four elements which influence on bacterial adhesion: the material, the micro organisms, antimicrobials and defence mechanisms. The influence of the material is more relevant at the initial states of adhesion where the proper material, its roughness or its superficial energy can have some influence. If there is some influence of the material in the bacterial adhesion, it relies on the features of the acquired film and on the specificity of the adsorved salivary proteins (receptors, which can be influenced by the composition of the material or the characteristics of its surface.

  18. Revisão sistemática do uso da dexametasona como terapia adjuvante na meningite bacteriana em crianças Revisión sistemática del uso de la dexametasona como terapia adyuvante en la meningitis bacteriana en niños Systematic review of dexamethasone as an adjuvant therapy for bacterial meningitis in children

    OpenAIRE

    2012-01-01

    OBJETIVO: Analisar a melhor evidência disponível nos últimos 15 anos com relação aos benefícios da terapia adjuvante com dexametasona na meningite bacteriana em população pediátrica. FONTES DE DADOS: Das bases de dados Medline, Lilacs e SciELO, foram analisados ensaios clínicos randomizados de 1996 a 2011, os quais comparavam a dexametasona ao placebo e/ou a outra terapia adjuvante em pacientes com meningite bacteriana diagnosticada laboratorialmente por critérios quimiocitológicos e/ou bacte...

  19. Resistencia bacteriana Bacterial resistance to antimicrobial agents

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    Jesualdo Fuentes

    1993-01-01

    Full Text Available

    Se presenta un panorama de la resistencia bacteriana incluyendo su fisiopatogenia y formas de presentación y se establecen algunas consideraciones generales de tipo clínico como auxiliares para racionalizar el uso de los antimicrobianos y evitar o retardar el problema de la resistencia; éste plantea la necesidad de un reordenamiento definitivo en la prescripción de antimicrobianos. No será tanto la creación o descubrimiento de nuevos antibióticos sino la racionalización del manejo de los existentes lo que permitirá alcanzar victorias sobre estos microorganismos. Es Importante mantener educación continua sobre el uso adecuado de los antimicrobianos desde los puntos de vista epidemiológico, farmacocinético y fisiopatogénico.

    An overview on bacterial resistance to antimicrobial agents is presented. It includes the different genetic mechanisms for Its development and the biochemical phenomena that explain It. Some clinical considerations are proposed in order to rationalize the use of these drugs and to avoid or delay the appearance of resistance.

  20. Protein export elements from Lactococcus lactis

    NARCIS (Netherlands)

    Perez-Martinez, Gaspar; Kok, Jan; Venema, Gerhardus; Dijl, Jan Maarten van; Smith, Hilda; Bron, Sierd

    1992-01-01

    Broad-host-range plasmids carrying α-amylase or β-lactamase reporter genes lacking a signal sequence were used to select export elements from Lactococcus lactis chromosomal DNA that could function as signal sequences. Fragments containing such elements were identified by their ability to direct the

  1. Environmental stress responses in Lactococcus lactis

    NARCIS (Netherlands)

    Sanders, JW; Venema, G; Kok, J

    1999-01-01

    Bacteria can encounter a variety of physical conditions during their life, Bacterial cells are able to survive these (often adverse) conditions by the induction of specific or general protection mechanisms. The lactic acid bacterium Lactococcus lactis is widely used for the production of cheese. Bef

  2. Heterologous Protein Expression by Lactococcus lactis

    NARCIS (Netherlands)

    Villatoro-Hernández, J.; Kuipers, O.P.; Saucedo-Cárdenas, O.; Montes-de-Oca-Luna, R.

    2012-01-01

    This chapter describes the use of Lactococcus lactis as a safe and efficient cell factory to produce heterologous proteins of medical interest. The relevance of the use of this lactic acid bacterium (LAB) is that it is a noncolonizing, nonpathogenic microorganism that can be delivered in vivo at a m

  3. Regulation of carbon catabolism in Lactococcus lactis.

    NARCIS (Netherlands)

    Aleksandrzak, T; Kowalczyk, M; Kok, J; Bardowski, J; Bielecki, S; Tramper, J; Polak, J

    2000-01-01

    The Lactococcus lactis IL1403 is a lactose negative, plasmid free strain. Nevertheless, it is able to hydrolyze lactose in the presence of cellobiose. In this work we describe identification of a gene involved in this process. The gene was found to be homologous to the sugar catabolism regulator, cc

  4. Functionality of Sortase A in Lactococcus lactis

    NARCIS (Netherlands)

    Dieye, Yakhya; Oxaran, Virginie; Ledue-Clier, Florence; Alkhalaf, Walid; Buist, Girbe; Juillard, Vincent; Lee, Chang Won; Piard, Jean-Christophe

    2010-01-01

    Lactococcus lactis IL1403 harbors a putative sortase A (SrtA) and 11 putative sortase substrates that carry the canonical LPXTG signature of such substrates. We report here on the functionality of SrtA to anchor five LPXTG substrates to the cell wall, thus suggesting that SrtA is the housekeeping so

  5. Resistencia bacteriana a los antibióticos

    OpenAIRE

    Crispín Pérez, Victor

    2014-01-01

    El descubrimiento de la antibiosis "in vitro" y el desarrollo de los antibióticos generó la ilusión del control de las enfermedades infecciosas bacterianas. Sin embargo, tan pronto como estas moléculas maravillosas fuero introducidas en la clínica, casi de inmediato surgieron las cepas bacterianas con resistencia adquirida, como se ha comprobado en las colecciones de cepas aisladas en las décadas del 50 del siglo pasado. Las moléculas de antibióticos inhiben o matan a las cepas sensibles, inh...

  6. Las enfermedades periodontales como infecciones bacterianas Periodontal diseases as bacterial infection

    Directory of Open Access Journals (Sweden)

    A. Bascones Martínez

    2005-12-01

    Full Text Available Las infecciones periodontales son un conjunto de enfermedades localizadas en las encías y estructuras de soporte del diente. Están producidas por ciertas bacterias provenientes de la placa bacteriana. Estas bacterias son esenciales para el inicio de la enfermedad, pero existen factores predisponentes del hospedador y microbianos que influyen en la patogénesis de la enfermedad. La microbiota bacteriana periodontopatógena es necesaria pero no suficiente para que exista enfermedad, siendo necesaria la presencia de un hospedador susceptible. Estas enfermedades se han clasificado en gingivitis, limitadas a las encías y periodontitis, extendidas a tejidos más profundos. La clasificación de las enfermedades periodontales ha ido variando a lo largo de los años y es en el International Workshop for a Clasification of Periodontal Diseases and Conditions, en 1999, cuando se aprueba la clasificación que se expone en este trabajo. En él, se hace una revisión global de los diferentes cuadros de las enfermedades periodontales. Posteriormente, se propone el empleo de antibioterapia de utilización sistémica como la amoxicilina, amoxicilina-clavulánico y metronidazol como primera opción de tratamiento coadyuvante de estas enfermedades.

  7. Programa preventivo da cárie dentária baseado no controle mecânico da placa bacteriana em crianças, por meio da profilaxia profissional periódica: Resultados após 25 anos de acompanhamento Dental caries prevention program based on the mechanical control of the bacterial plaque in children, through the periodic professional prophylaxis: Results after 25 years of attendance

    Directory of Open Access Journals (Sweden)

    José Eduardo de Oliveira Lima

    2009-06-01

    Full Text Available OBJETIVOS: o objetivo deste trabalho foi verificar a incidência de cárie dentária em um programa de prevenção aplicado durante 25 anos em clínica particular. METODOLOGIA: participaram desse programa 640 crianças de ambos os gêneros, na faixa etária de 3 a 15 anos de idade. O programa foi baseado no controle mecânico da placa bacteriana dentária por meio da profilaxia profissional com jato de bicarbonato de sódio com uma periodicidade mensal. A incidência de cárie foi verificada por meio de exames clínicos durante as sessões de atendimento e radiográficos anualmente. A média de idade das crianças ao ingressarem no programa foi de 7,8 anos. RESULTADOS: antes de ingressar no programa, as crianças apresentaram, em média, 5,3 faces cariadas, enquanto após o programa a média foi de 0,18. A incidência de cáries por ano antes do programa foi de 0,9 faces cariadas e durante o programa de 0,03. O tempo de permanência das crianças no programa foi, em média, de 52,6 meses, e a média de faltas foi de 0,5 falta por ano. Esses resultados demonstram o sucesso do programa, principalmente por ter uma filosofia que procura o equilíbrio da biodiversidade da cavidade bucal, sem o risco de produzir efeitos colaterais indesejáveis. CONCLUSÕES: conclui-se, assim, que esse parece ser o caminho mais curto para resolver o problema da cárie dentária, ou seja, o controle mecânico da placa bacteriana dentária através da profilaxia profissional mensal, pois é um método de prevenção possível de ser aplicado em qualquer criança, independentemente de suas condições psicomotoras e sociais, e que proporciona a melhor relação custo-benefício, além de estar de acordo com os conceitos mais atuais de cárie e de seus fatores etiológicos. Em função da faixa etária das crianças, o programa é de suma importância para clínicas de Odontopediatria e Ortodontia.AIM: This study investigated the incidence of dental caries in a prevention

  8. Duchas vaginales y otros riesgos de vaginosis bacteriana

    Directory of Open Access Journals (Sweden)

    Natividad Chávez

    2009-07-01

    Full Text Available La vaginosis bacteriana (VB es una infección caracterizada por el cambio en la microflora de la vagina, se asocia con resultados adversos del embarazo y a la adquisición de infecciones de transmisión sexual (ITS, que incluyen el VIH. Objetivos. Identificar la asociación entre el uso de duchas vaginales y otros factores de riesgo con VB. Materiales y métodos. Se realizó un estudio transversal en 1252 mujeres que asistieron al servicio de planificación familiar de tres hospitales nacionales y un instituto especializado de Lima, durante el año 1997. Se utilizó un cuestionario estructurado donde se registró las variables sociodemográficas y las características del estilo de vida de las participantes. La VB fue diagnosticada mediante el puntaje de Nugent. Se empleó análisis de regresión logística para calcular odds ratio (OR e intervalos de confianza al 95%. Resultados. La edad promedio fue 25,1 ± 4,7 años, el 23,4% tenían más de 11 años de educación. La prevalencia de VB fue 20,1%. Las mujeres que practicaban duchas vaginales (OR: 2,28; IC95%: 1,0- 5,0, que tenían dos o más parejas sexuales (OR: 2,0; IC95%: 1,2-3,5 y que iniciaron una relación sexual a una edad temprana (OR: 1,4; IC95%: 1,0 -1,9 tuvieron mayor probabilidad de adquirir VB. Conclusiones. El uso de duchas vaginales es un factor de riesgo de VB en mujeres peruanas. Los programas destinados a la salud de la mujer deben abordar las repercusiones perjudiciales para la salud asociados con las duchas vaginales.

  9. DUCHAS VAGINALES Y OTROS RIESGOS DE VAGINOSIS BACTERIANA

    Science.gov (United States)

    Chávez, Natividad; Molina, Helfer; Sánchez, Jorge; Gelaye, Bizu; Sánchez, Sixto E.

    2010-01-01

    Vaginosis bacteriana (VB) es una infección caracterizada por el cambio en la microflora de la vagina, asociándose a resultados adversos del embarazo y a la adquisición de infecciones de transmisión sexual (ITS), incluyendo el VIH. En este estudio se buscó la asociación entre el uso de duchas vaginales y otros factores de riesgos con VB. Se usó un diseño observacional descriptivo transversal prospectivo, en 1,252 mujeres que asistieron al servicio de planificación familiar de tres hospitales nacionales (Dos de Mayo, Arzobispo Loayza, San Bartolomé) y el Instituto Materno Perinatal, durante el año 1997. Se utilizó un cuestionario estructurado donde se registraron variables socio demográficas y características del estilo de vida de las participantes. VB fue diagnosticada mediante el puntaje de Nugent. Se empleó análisis de regresión logística para calcular odds ratio (OR) e intervalos de confianza al 95%. La edad promedio de las participantes fue 25.1 ± 4,7 años, el 23.4% tenían más de 11 años de educación. La prevalencía de VB fue 20,1%. Las mujeres que practicaban duchas vaginales tuvieron 2.28 veces (OR = 2.28, IC 95% [1.0–5.0]) mayor probabilidad de tener VB comparado con aquellas que no lo practicaban. Tener dos o más parejas sexuales estuvo asociado con 2.0 veces (OR =2.0, IC 95% [1.2–3.5]) mayor probabilidad de adquirir VB comparado con aquellas que habían tenido solo una pareja sexual. Las participantes que iniciaron una relación sexual a una edad temprana tuvieron 1.4 veces (OR=1.4, IC 95% [1.0 –1.9]) mayor probabilidad de adquirir VB. El uso de duchas vaginales es un factor de riesgo de VB. Los programas destinados a la salud de la mujer deben abordar las repercusiones perjudiciales para la salud asociados con las duchas vaginales. PMID:21132048

  10. Sobre la resistencia bacteriana hacia antibióticos de acción bactericida y bacteriostática

    OpenAIRE

    Jhoana P. Romero L.; Eduardo Ibargüen Mondragón

    2014-01-01

    En este artículo se formula un modelo matemático simple que describe la interacción entre bacterias sensibles y resistentes a múltiples antibióticos de acción bactericida y bacteriostática de forma simultánea, en el supuesto de que la adquisición de resistencia bacteriana se da a través de mutaciones espontáneas y adquiridas por la exposición a diferentes antibióticos. El análisis cualitativo revela la existencia de un equilibrio libre de bacterias, un equilibrio solo con ba...

  11. Validación del método LAL para determinar endotoxinas bacterianas en el inyectable heparina sódica

    Directory of Open Access Journals (Sweden)

    Nancy Burguet

    2012-12-01

    Full Text Available Dentro del control de la calidad de los productos farmacéuticos, la United State Pharmacopeia establece la cuantificación de endotoxinas bacterianas por el método de lisado de amebocito de Limulus , como monitor de pirógenos para más del 90% de los parenterales que regula. Este método se aplicó de forma específica a vacunas bacterianas y virales, agentes antineoplásicos, radiofármacos y parenterales que se producen en la industria médico farmacéutica. En el presente trabajo se mostró la metodología a seguir para realizar la validación de la técnica de determinación de endotoxinas bacterianas por el método de gelificación. Para ello se confirmó la sensibilidad del reactivo utilizado (0,03125 UE/mL y la validez de los analistas para poder obtener resultados confiables. Las pruebas preliminares para el producto ensayado, heparina sódica 5000 UI/mL, demostraron que este producto no potencia ni inhibe la reacción del reactivo. Se escogió la dilución de trabajo (1/128 para la validación del método. De esta manera quedaron estandarizadas las condiciones para la validación del test de lisado de amebocito de Limulus por gelificación en este producto parenteral, método que se hace extensivo a la determinación de endotoxinas bacterianas en vacunas y en otros medicamentos por vía de administración intravenosa.

  12. Nuevos métodos bacteriológicos para detectar y evitar la resistencia bacteriana

    Directory of Open Access Journals (Sweden)

    Margaret Ordoñez-Smith de Danies

    2003-09-01

    Full Text Available

    DEFINICIÓN DE LA RESISTENCIA

    De acuerdo al COC (Centro de Control de Enfermedades de Estados Unidos, la resistencia se da cuando un medicamento deja de inhibir el crecimiento o matar un microorganismo. 

    Hay dos tipos de resistencia la adquirida y la clínica. La adquirida se realiza en el laboratorio a través de las mutaciones o por transferencia de genes, sistemas de conjugación, transducción y transformación.

    La resistencia clínica es la observada en la práctica médica, donde no todos los organismos son igualmente sensibles o resistentes a cierto antibiótico y que requiere la ayuda de técnicas de laboratorio para medir cuantitativamente o cualitativamente dicho proceso.

    MECANISMOS DE LA RESISTENCIA BACTERIANA

    En la detección de la Resistencia Bacteriana se han identificado diferentes mecanismos utilizados por las bacterias: destrucción o inactivación enzimática, cambios en la permeabilidad de la membrana interna, alteraciones de los precursores de la pared celular, de la membrana y de los ribosomas.

    Para los años 90 se dispuso de una serie de antimicrobianos como betalactámicos, aminoglucósidos, macrólidos, sulfonamidas, trimetoprim, cloranfenicol, glicopéptidos, rifampicina, quinolonas, tetraciclinas....

     

  13. Bacteremia secundaria a una traslocación bacteriana, una complicación de la obstrucción intestinal mecánica

    OpenAIRE

    Chavarriaga Soto, Julián Ánd´res; Pontificia Universidad Javeriana, Bogotá, Colombia.

    2016-01-01

     Introduccion: la obstrucción intestinal es el trastorno quirúrgico más frecuente del intestino delgado. Como parte del manejo médico se ha sugerido el tratamiento empírico con antibióticos por el hallazgo patológico de traslocación bacteriana secundaria a la obstrucción. Métodos: se llevó a cabo una revisión de la literatura en las bases de datos Medline, Embase y PubMed y se incluyeron artículos con resultados sobre traslocación bacteriana, fisiología de la barrera intestinal, obstrucción i...

  14. Flora intermediária em mulheres em idade reprodutiva: aspectos inflamatórios, atividade de sialidases e carga bacteriana

    OpenAIRE

    Greatti, Mariana Morena de Vieira Santos [UNESP

    2014-01-01

    Espécies de lactobacilos são os principais componentes da microbiota vaginal e a manutenção do predomínio lactobacilar é importante para proteção desse ambiente contra possíveis patógenos. A vaginose bacteriana é uma condição em que se observa a perda de lactobacilos e substituição desses microrganismos por espécies bacterianas, anaeróbias em sua maioria. Tal condição pode acarretar inúmeras complicações ginecológicas e obstétricas, como o aumento do risco de aquisição de infecções sexualment...

  15. Aislamiento e identificación de diez cepas bacterianas desnitrificantes a partir de un suelo agrícola contaminado con abonos nitrogenados proveniente de una finca productora de cebolla en la Laguna de Tota, Boyacá, Colombia

    OpenAIRE

    ostos ortiz, olga lucia; Benavides López de Mesa, Joaquín; Quintero, Gladys

    2006-01-01

    Este articulo presenta los resultados de la versatilidad adaptativa y tolerancia de una consorcio bacteriano constituido por 10 cepas bacterianas endémicas de un suelo agrícola contaminado, proveniente de una finca productora de cebolla ubicada en la laguna de Tota en Aquitania, Boyacá, Colombia, expuesto al uso incontrolado de fertilizantes nitrogenados. La consorcio bacteriano aislado del suelo está conformado por: Bacillus megaterium, Bacillus licheniformis, Pseudomonas stutzeri, Acinetoba...

  16. CHARACTERIZATION OF LACTOCOCCUS STRAINS AND THEIR USING IN DAIRY TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Gabriel Greif

    2012-02-01

    Full Text Available Lactococcus lactis species is one of the most important groups of lactic acid bacteria that are used in the dairy industry. Lactococci are generally found on plants and the skins of animals. Special interest is placed on the study of Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris, as they are the strains used as starter cultures in industrial dairy fermentation. The major functions of this species in dairy fermentation are the production of lactic acid, formation of flavour and aroma compounds, development of ripened cheese texture and antimicrobial activity against spoilage bacteria and moulds.doi:10.5219/162

  17. Evaluación de la congelación para conservación de especies autóctonas bacterianas

    OpenAIRE

    2005-01-01

    Los microorganismos bacterianos constituyen una buena parte de la biodiversidad de nuestro planeta y la importancia de su conocimiento y preservación se ha incrementado a medida que se descubren sus múltiples utilidades en diferentes campos. La conservación se puede hacer por diferentes métodos y uno de los que brinda mejores resultados es la congelación; por ello se realizó este proyecto cuyo objetivo fue evaluar los efectos de la congelación en 18 especies bacterianas autóctonas de la colec...

  18. Una nueva ultraestructura de ópalo CT en silcretas. Posible indicador de influencia bacteriana

    Directory of Open Access Journals (Sweden)

    Bustillo, Mª A.

    1995-04-01

    Full Text Available Electron microscope observations of opaline silcretes found in the playa of a Miocene shallow lake reveal new opal CT microstructures. These microstructures are made up of fibres, filaments or rods, which are formed, in tum by coalesced microspheres or microhemispheres (0,1-0,2 µ diameter. They are up to 10 µ in length although larger ones could exist. They are straight, bent, wavy or even hairpin shaped. These microstructures comprise part of the opaline mass of the silcretes and are very similar to both neogenic opaline structures which are formed by bacterial intluence and to silicified biofilms. Therefore microbial mediation could exist in the genesis of this opal CT, although a possible inorganic origin by silicification of sepiolite is also considered.Un estudio mediante MEB de silcretas miocenas opalinas formadas por silicificación de playas en un ambiente de «playa-lake» pone de manifiesto la existencia de una nueva microestructura de ópalo CT. Esta microestructura denominada en general fibrosa, se manifiesta por la presencia de multitud de fibras, filamentos o varillas formadas por la alineación de microesferas o microhemisferas que presentan un diámetro entre 0,1 y 0,2 µ. Las fibras, filamentos o varillas tienen formas variables: rectas, curvadas, onduladas y «en horquilla», y presentan longitudes de hasta 10 µ, aunque podrían existir longitudes mayores. La disposición organizada de las microesferas en filamentos o fibras, constituyendo la masa general del ópalo, y su parecido con microestructuras opalinas que han sido formadas por influencia bacteriana, hacen considerar esta hipótesis, aunque no se puede descartar totalmente un origen inorgánico por silicificación de sepiolita.

  19. Avaliação da microbiota bacteriana do queijo de coalho artesanal produzido na região Agreste do estado de Pernambuco

    Directory of Open Access Journals (Sweden)

    R.A. Silva

    2012-12-01

    Full Text Available O objetivo desta pesquisa foi avaliar a qualidade microbiológica e o perfil ácido-láctico do queijo de coalho artesanal. Todas as amostras de queijo apresentaram coliformes totais, termotolerantes e presença de Escherichia coli, porém com os valores dentro dos padrões estabelecidos pela legislação vigente no país. O perfil ácido-láctico estudado mostrou uma microbiota heterogênea, constituída por lactobacilos, lactococos, estreptococos e enterococos, confirmadas as espécies Enterococcus faecalis, Enterococcus faecium, Streptococcus thermophilus e Lactococcus lactis.

  20. A RIFAMPICINA NA DESCONTAMINAÇÃO BACTERIANA DE EXPLANTES DE MAMOEIRO PROVENIENTES DO CAMPO

    Directory of Open Access Journals (Sweden)

    GIOVANNI RODRIGUES VIANNA

    1997-01-01

    Full Text Available Observou-se alta contaminação bacteriana nos explantes de mamoeiro introduzidos in vitro, a partir de plantas matrizes desenvolvidas no campo, independentemente da época do ano em que se realizaram as coletas. O uso de desinfestantes superficiais, como álcool e hipoclorito de sódio, garantiram níveis aceitáveis de controle apenas para fungos, não para bactérias. A rifampicina, por tratamento de imersão ou introdução em meio de cultura, controlou satisfatoriamente as contaminações de caráter endofítico, obtendo-se 70% de explantes sadios, sem sinais de fitotoxicidade.High contamination by bacteria was observed in papaya tissue cuttings introduced in vitro from plants grown in the field, independent of the period of the year that samples were collected. The use of alcohol and sodium hypoclorite did not guarantee good bacteria control. Rifampicin, added as an immersion solution treatment or in the culture media, controlled the internal contamination of explants, without damaging the cuttings. Up to 70% of healthy tissue explants were obtained by the use of rifampicin.

  1. Infecções bacterianas tratadas com Ro 6-2580

    Directory of Open Access Journals (Sweden)

    Paulo F. A. Lopes

    1970-10-01

    Full Text Available Nova combinação medicamentosa composta de sulfametoxazól e trimetoprim ("Bactrim", com efeito bactericida sobre germes Gram negativos e Gram positivos, foi ensaiada no tratamento de 15 casos de salmonelose e 9 casos de infecções bacterianas. Os resultados foram favoráveis, tanto nas salmoneloses, como em infecções por estafilococos, shigelas, pneumococos e coliformes. A remissão do estado tóxico nos casos de febre tifóide foi observada dentro de 48 horas, e o tempo médio para desaparecimento da febre e demais sintomas, nessa infecção, foi de 3 dias. Foram constatados efeitos secundários em alguns pacientes, tais como hipertermia medicamentosa, farmacodermia, vômitos, linfomonocitose e eosinofilia, possivelmente relacionados a posologia excessiva, e todos remissíveis. Os autores concluem pela utilidade do novo medicamento na terapêutica de salmoneloses, estafilococcias e outras infecções.

  2. Controlo da placa bacteriana em reabilitações implanto-suportadas: revisão da literatura

    OpenAIRE

    Marmelo, Catarina Filipa Dias

    2016-01-01

    Trabalho final do 5º ano com vista à atribuição do grau de mestre no âmbito do ciclo de estudos de Mestrado Integrado em Medicina Dentária apresentado à Faculdade de Medicina da Universidade de Coimbra. Introdução: A reabilitação oral com implantes tem tido uma divulgação exponencial graças aos seus resultados, estéticos e funcionais, altamente satisfatórios. A falta de motivação para a higiene oral e de destreza manual por parte do doente levam à acumulação de placa bacteriana, p...

  3. Sobre la resistencia bacteriana hacia antibióticos de acción bactericida y bacteriostática

    Directory of Open Access Journals (Sweden)

    Jhoana P. Romero L.

    2014-01-01

    Full Text Available En este artículo se formula un modelo matemático simple que descri- be la interacción entre bacterias sensibles y resistentes a múltiples antibióticos de acción bactericida y bacteriostática de forma simultánea, en el supuesto de que la adquisición de resistencia bacteriana se da a través de mutaciones espontáneas y adquiridas por la exposición a diferentes antibióticos. El análisis cualitativo revela la existencia de un equilibrio libre de bacterias, un equili- brio solo con bacterias resistentes y un equilibrio endémico donde coexisten ambas poblaciones de bacterias.

  4. Evaluación de la eficacia de dos prescripciones de cepillos dentales en la remoción de placa bacteriana en pacientes ortodóncicos

    OpenAIRE

    Zúñiga García,D; Pastén Castro,EJ; Araya-Díaz,PA; Palomino Montenegro,H

    2012-01-01

    La aparatología empleada en los tratamientos de ortodoncia, favorece la retención de placa bacteriana y dificulta su eliminación por parte del paciente, aumentando el riesgo de desarrollar caries, manchas blancas y enfermedad periodontal. Diferentes cepillos dentales se han desarrollado para facilitar la mantención de una adecuada higiene oral en estos pacientes, sin embargo, se ha observado que los cepillos comunmente indicados (cepillo ortodóncico mas cepillo unipenacho), no siempre son bie...

  5. Reunión regional de vigilancia de la resistencia bacteriana a los antibióticos 2009. Lima, Perú

    OpenAIRE

    Sacsaquispe Contreras, Rosa

    2010-01-01

    Artículo online La Reunión Regional de Vigilancia de la Resistencia Bacteriana a los Antibióticos 2009, tuvo como sede la ciudad de Lima, se realizó durante los días 03 y 04 de diciembre de 2009, y fue organizada por USAID y la Organización Panamericana de la Salud (OPS). A la actividad asistieron participantes de 20 países de la Región, representando a sus respectivos Ministerios de Salud, Institutos de Salud, OPS, además de centros como la Caribbean Epidemiology Center (CAREC).

  6. Controle alternativo da murcha bacteriana do pimentão utilizando óleos essenciais vegetais e silicato de cálcio.

    OpenAIRE

    Aldenir de Oliveira Alves

    2012-01-01

    A murcha bacteriana do pimentão, causada por Ralstonia solanacearum (Rs) raça 1, é uma fitobacteriose importante em Pernambuco e outros estados do Brasil. Este trabalho teve como objetivos testar o efeito de óleos vegetais e do silício (Si) no controle alternativo desta doença, seus efeitos diretos sobre Rs e verificar os possíveis mecanismos envolvidos nestes processos. Os óleos essenciais de bergamota, canela, capim limão, copaíba, eucalipto citriodora, eucalipto globulus, funcho, hortel...

  7. Medición de cambios cuantitativos de la microbiota subgingival posterior a la remoción de placa bacteriana supragingival

    OpenAIRE

    C. Godoy; Melej,C; Silva, N

    2010-01-01

    Uno de los campos de interés en el estudio de la microbiología periodontal para muchos investigadores ha sido identificar si es posible que los microorganismos responsables del origen y progresión de la enfermedad periodontal que habitan sobre el margen gingival (supragingival) y bajo este (subgingival) tengan una relación directa que permita mantener interacciones influyentes en el crecimiento y desarrollo de las diferentes especies bacterianas que habitan en los tejidos periodontales. Por l...

  8. REMOÇÃO DE PLACA BACTERIANA DENTÁRIA APÓS O USO DE ENXAGUANTES BUCAIS PRÉ-ESCOVAÇÃO

    OpenAIRE

    Regina da Silva Miranda

    2012-01-01

    Este trabalho teve como objetivo avaliar a influência do uso de enxaguantes bucais pré-escovação na remoção da placa bacteriana por adolescentes. Foi realizado um estudo seguindo o modelo cruzado, de duplo mascaramento, com duração total de 25 dias, com 4 dias de intervalo entre as fases. O protocolo da pesquisa obteve aprovação pelo Comitê de Ética em pesquisa da UFSM. Trinta e oito adolescentes (idade média de 13 anos) de uma escola estadual da cidade de Santa MariaRS, uti...

  9. LANTIBIOTIC NISIN: NATURAL PRESERVATIVE FROM LACTOCOCCUS LACTIS

    Directory of Open Access Journals (Sweden)

    Suganthi.V

    2012-01-01

    Full Text Available The increasing demand for high quality safe foods that are not extensively processed has created a niche for natural food preservative. Studies confirm that food allergies due to chemical preservatives affect as much as 2.5% of the population. Recent research had suggested bacteriocins (Nisin are the ideal biological food preservative. Nisin was proteinaceous antibacterial substances produced by Lactococcus lactis, a homofermentative bacterium. Naturally nisin occurs in two different forms nisin A and nisin Z. Nisin has wide range of inhibitory mode of action on Gram negative bacteria and food borne pathogens. Food preservation is a continuous war against the microorganisms spoiling the food or making it unsafe. So, nisin is actually the only lantibiotic bacteriocins used as a food preservative. This review paper will discuss about the Lactococcal strain used for the production of nisin, different forms of nisin, the mode of action of nisin, the cost reductive methods for the production and purification of nisin. So that it can be used in large scale industry for the high yield of nisin and the wide application of nisin in food industries.

  10. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    EDINSON ANDRÉS ACOSTA

    2009-01-01

    Full Text Available El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y so- cioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como "vulnerable" y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 106 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >105 ufc mL-1 . El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.

  11. Actividad sialidasa en mujeres con vaginosis bacteriana Sialidase activity in women with bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    Adriana M. Ombrella

    2006-04-01

    Full Text Available La vaginosis bacteriana (VB es un síndrome caracterizado por el sobrecrecimiento bacteriano de flora endógena Gram negativa, que desplaza a la flora lactobacilar normal. Dentro de las enzimas bacterianas, las sialidasas han sido consideradas factores de virulencia de muchos microorganismos patógenos que colonizan las distintas mucosas. Su presencia en fluidos vaginales puede estar correlacionada con VB. El propósito de este estudio fue comprobar la actividad de dicha enzima en mujeres con este síndrome y sin evidencia clínica de infección genital. Se estudiaron 112 mujeres (51 fueron pacientes con VB y 61 mujeres con flora colonizante habitual. Para la cuantificación de la actividad sialidasa se empleó la técnica basada en la hidrólisis enzimática de un derivado ácido del ácido metoxifenil acetil murámico. En la población estudiada se encontró que ambos grupos mostraron valores comprendidos entre 0.5 a 5.1 nmoles de metoxifenol, mientras que 11 de 52 pacientes con VB (21.17%, registraron valores superiores a 5.1 nmoles. La presencia de actividad sialidasa solamente no es índice de VB, excepto para valores mayores de 5.5 nmoles de metoxifenol, producidos en la reacción enzimática.Bacterial vaginosis (VB is a syndrome characterized by overgrowth of endogenous Gram negative bacterial flora and the lack of the normal flora. Within bacterial enzymes, sialidases have been considered a virulence factor of many pathogenic microorganisms colonizing the different mucous membranes. Their presence in vaginal discharges can be correlated with VB. The aim of this study was to detect the activity of this enzyme in women with this syndrome and without clinical evidence of genital infection. Out of a total 112 women studied, 51 were patients with VB and the other 61 women presented normal vaginal flora. For the quantification of enzyme activity, the technique based on the enzymatic hydrolysis of a derivative acid of the acetyl metoxifenil

  12. Eficacia de cinco desinfectantes para la reducción bacteriana doméstica

    Directory of Open Access Journals (Sweden)

    Julián Stambullian

    2011-06-01

    Full Text Available El uso adecuado de hipoclorito de sodio, sales de amonio cuaternario y triclosán ha demostrado ser eficaz para eliminar gérmenes dentro del hogar. Nuestro objetivo fue evaluar la eficacia inmediata, a la semana y al mes del uso controlado de cinco productos con estos componentes, comparados con otros productos de uso habitual. Se incluyeron 32 hogares de clase media de la Ciudad de Buenos Aires y la periferia en un estudio con intervención, abierto, aleatorizado, y de grupos paralelos, durante 6 meses. La mitad de los hogares fue seleccionada para usar hipoclorito de sodio, sales de amonio cuaternario y triclosán en la cocina y el baño durante un mes. El grupo control mantuvo prácticas habituales de limpieza doméstica. Se tomaron muestras para recuento y tipificación bacteriana de los sitios estudiados: muestras basales (sin discriminación de grupo en cocina, que presentaron recuento bacteriano promedio de 66.0 UFC/cm²; baño: 40.1 UFC/cm². Las muestras inmediatas a la limpieza (sin discriminación de grupo: en cocina: 0.8 UFC/cm²; baño: <1 UFC/cm². A la semana (grupo intervenido vs. grupo control: cocina 18.0 vs. 32.5 UFC/cm²; baño 12.7 vs. 7.7 UFC/cm². Al mes (intervenido vs. control: cocina: 60.1 vs. 62.1 UFC/cm²; baño: 37.0 vs. 42.0 UFC/cm². Se observó una notable disminución de la carga bacteriana en ambos grupos, lo que sugiere que no sólo la calidad de los productos sino también la educación en el uso desempeñan un papel clave en la desinfección del hogar. Este enfoque podría ser una herramienta importante para prevenir infecciones transmitidas por alimentos, dado que los coliformes fecales predominaron ampliamente en todas las muestras tipificadas.

  13. Estudio de la expresión de enzimas del metabolismo de aminoácidos en Lactococcus lactis

    OpenAIRE

    García-Cayuela, Tomás

    2011-01-01

    Los aminoácidos son fundamentales para la supervivencia y el desarrollo de bacterias. Son las principales fuentes de nitrógeno y están implicados en la producción de energía, el control del pH intracelular y la regeneración de cofactores. Además, son los precursores de una larga variedad de compuestos volátiles en Lactococcus lactis y, por ello, diversas enzimas son consideradas clave para su formación, como aminotransferasas, deshidrogenasas, liasas y decarboxilasas, entre otras. Estas enzim...

  14. Alternative lactose catabolic pathway in Lactococcus lactis IL1403

    NARCIS (Netherlands)

    Aleksandrzak-Piekarczyk, T; Kok, J; Renault, P; Bardowski, J

    2005-01-01

    In this study, we present a glimpse of the diversity of Lactococcus lactis subsp. lactis IL1403 beta-galactosidase phenotype-negative mutants isolated by negative selection on solid media containing cellobiose or lactose and X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside), and we identif

  15. Luciferase detection during stationary phase in Lactococcus lactis

    NARCIS (Netherlands)

    Bachmann, H.; Santos, dos F.; Kleerebezem, M.; Hylckama Vlieg, van J.E.T.

    2007-01-01

    The luminescence signal of luxAB-encoded bacterial luciferase strongly depends on the metabolic state of the host cell, which restricts the use of this reporter system to metabolically active bacteria. Here we show that in stationary-phase cells of Lactococcus lactis, detection of luciferase is sign

  16. Nucleotide metabolism in Lactococcus lactis: Salvage pathways of exogenous pyrimidines

    DEFF Research Database (Denmark)

    Martinussen, Jan; Andersen, Paal Skytt; Hammer, Karin

    1994-01-01

    By measuring enzyme activities in crude extracts and studying the effect of toxic analogs (5-fluoropyrimidines) on cell growth, the metabolism of pyrimidines in Lactococcus lactis was analyzed. Pathways by which uracil, uridine, deoxyuridine, cytidine, and deoxycytidine are metabolized in L. lact...

  17. Regulatory phenotyping reveals important diversity within the species Lactococcus lactis

    NARCIS (Netherlands)

    Bachmann, H.; Starrenburg, M.; Dijkstra, A.; Molenaar, D.; Kleerebezem, M.; Rademaker, J.L.W.; Hylckama Vlieg, van J.E.T.

    2009-01-01

    The diversity in regulatory phenotypes among a collection of 84 Lactococcus lactis strains isolated from dairy and nondairy origin was explored. The specific activities of five enzymes were assessed in cell extracts of all strains grown in two different media, a nutritionally rich broth and a relati

  18. Transcriptional regulation of central amino acid metabolism in Lactococcus lactis

    NARCIS (Netherlands)

    Larsen, Rasmus

    2005-01-01

    This thesis describes the functional characterisation of the transcriptional regulators GlnR, ArgR and AhrC of Lactococcus lactis, which are responsible for the control of genes involved in the metabolism of the amino acids glutamine, glutamate and arginine. A chromosomal glnR deletion mutant was ma

  19. Nisin-Producing Lactococcus lactis Strains Isolated from Human Milk

    OpenAIRE

    Beasley, Shea S.; Saris, Per E.J.

    2004-01-01

    Characterization by partial 16S rRNA gene sequencing, ribotyping, and green fluorescent protein-based nisin bioassay revealed that 6 of 20 human milk samples contained nisin-producing Lactococcus lactis bacteria. This suggests that the history of humans consuming nisin is older than the tradition of consuming fermented milk products.

  20. Increased production of folate by metabolic engineering of Lactococcus lactis

    NARCIS (Netherlands)

    Sybesma, W.F.H.; Starrenburg, M.; Kleerebezem, M.; Mierau, I.; Vos, de W.M.; Hugenholtz, J.

    2003-01-01

    The dairy starter bacterium Lactococcus lactis is able to synthesize folate and accumulates large amounts of folate, predominantly in the polyglutamyl form. Only small amounts of the produced folate are released in the extracellular medium. Five genes involved in folate biosynthesis were identified

  1. Structure-function analysis of multidrug transporters in Lactococcus lactis

    NARCIS (Netherlands)

    van Veen, HW; Putman, M; Margolles, A; Sakamoto, K; Konings, WN

    1999-01-01

    The active extrusion of cytotoxic compounds from the cell by multidrug transporters is one of the major causes of failure of chemotherapeutic treatment of tumor cells and of infections by pathogenic microorganisms. A multidrug transporter in Lactococcus lactis, LmrA, is a member of the ATP-binding c

  2. Lactococcus lactis as host for overproduction of functional membrane proteins

    NARCIS (Netherlands)

    Kunji, ERS; Slotboom, DJ; Poolman, B

    2003-01-01

    Lactococcus lactis has many properties that are ideal for enhanced expression of membrane proteins. The organism is easy and inexpensive to culture, has a single membrane and relatively mild proteolytic activity. Methods for genetic manipulation are fully established and a tightly controlled promote

  3. Multidrug transporters and antibiotic resistance in Lactococcus lactis

    NARCIS (Netherlands)

    Poelarends, GJ; Mazurkiewicz, P; Konings, WN

    2002-01-01

    The Gram-positive bacterium Lactococcus lactis produces two distinct multidrug transporters, designated LmrA and LmrP, that both confer resistance to a wide variety of cationic lipophilic cytotoxic compounds as well as to many clinically relevant antibiotics. While LmrP is a proton/drug antiporter t

  4. Sialoadenitis bacteriana crónica recurrente de la infancia. Caracterización clínica

    Directory of Open Access Journals (Sweden)

    Carlos Ávila-Sánchez

    2015-03-01

    Full Text Available La sialoadenitis recurrente es el segundo cuadro inflamatorio más frecuente que afecta a la glándula parótida, precedida por la parotiditis viral. Esta afección tiene un cuadro clínico muy similar a la sialoadenitis, motivo por el cual se debe considerar dentro de los  iagnósticos diferenciales. La sialoadenitis recurrente se caracteriza por episodios periódicos de inflamación y aumento de volumen de la glándula parótida acompañados de fiebre y malestar general que alternan con intervalos de remisión en los que la glándula es clínicamente asintomática. En el Instituto Nacional de Pediatría consideramos al concepto Sialoadenitis bacteriana crónica recurrente de la infancia como la definición más específica y completa para referirse a esta enfermedad. Debido a su recurrencia decidimos escribir este artículo para señalar sus características clínicas.

  5. INTERACCIONES ENTRE Gluconacetobacter diazotrophicus Y LA COMUNIDAD BACTERIANA ENDÓFITA DE LA CAÑA DE AZÚCAR

    Directory of Open Access Journals (Sweden)

    Marcia M. Rojas

    2007-01-01

    Full Text Available Gluconacetobacter diazotrophicus es una bacteria endófita de caña de azúcar, que se ha comprobado que es capaz de fijar cantidades considerables de nitrógeno y producir sustancias estimuladoras del crecimiento vegetal, lo cual puede ser de suma importancia en el mejoramiento de este cultivo sobre bases agroecológicas. En el presente trabajo se demuestran, por primera vez, las interacciones que esta especie establece con otros representantes de la comunidad bacteriana endófita de la caña de azúcar empleando el micrométodo en portaobjetos. G. diazotrophicus ejerce efecto antagonista sobre otros miembros de la comunidad, lo cual está influido por las cepas y el tiempo de crecimiento de la especie, que a su vez es estimulada por otras presentes en el interior de la caña de azúcar. Este hecho pudiera contribuir a potenciar la promoción del crecimiento que puede ejercer G. diazotrophicus en la caña de azúcar.

  6. Acumulación de antibioticos y su efecto sobre la comunidad bacteriana presente en sedimentos de piscinas camaroneras

    OpenAIRE

    Montoya, Nelson; Uyaguari, Miguel; Sotomayor, Mariuxi

    2003-01-01

    ACUMULACION DE ANTIBIOTICOS Y SU EFECTO SOBRE LA COMUNIDAD BACTERIANA PRESENTE EN SEDIMENTOS DE PISCINAS CAMARONERAS La mayor preocupación que ha surgido al considerar el uso de agentes antibacteriales en acuicultura, es la posibilidad de que sus residuos puedan estimular la presencia de resistencia bacteriana.

  7. Perfil etiológico das meningites bacterianas em crianças Etiological profile of bacterial meningitis in children

    Directory of Open Access Journals (Sweden)

    Orlando C. Mantese

    2002-12-01

    Full Text Available Objetivo: analisar o perfil etiológico e alguns aspectos epidemiológicos das crianças com meningite bacteriana, internadas em um hospital público universitário. Métodos: foram seguidas, prospectivamente, as crianças internadas com meningite bacteriana, diagnosticada segundo os critérios clínicos e laboratoriais habituais. Foram excluídos os casos de meningite pós-trauma, de meningite na vigência de derivação liquórica, ou de defeitos congênitos do tubo neural, e de meningite tuberculosa. Resultados: foram analisadas 415 crianças internadas com diagnóstico de meningite bacteriana, no Hospital de Clínicas da Universidade Federal de Uberlândia, no período de 01/01/1987 a 31/01/2001. O agente etiológico foi identificado em 315 pacientes (75,9%, sendo de modo definitivo em 289 (69,3% e presuntivo, por intermédio da bacterioscopia, em outros 26 (6,6%. Os agentes mais comumente identificados foram o Haemophilus influenzae b (54,2%, o meningococo (20,6% e o pneumococo (18,1% dos 315 pacientes. O tratamento antimicrobiano prévio, detectado em 47,2% dos casos, causou uma diminuição significante no rendimento das culturas de sangue (de 50,8% para 38,7% e de liquor (71,7% para 57,6%. Houve um predomínio do acometimento de crianças com idade até 48 meses pelo Haemophilus influenzae b, particularmente em relação ao meningococo. A letalidade geral foi de 10,1%, com diferença significante entre a letalidade do pneumococo, de 17,5%, e a do meningococo, de 4,6%. Conclusões: as crianças afetadas por Haemophilus influenzae b e por pneumococo foram mais jovens que aquelas com meningite por meningococo. A hemocultura e a cultura de liquor continuam sendo importantes recursos laboratoriais para o diagnóstico etiológico da meningite bacteriana, apesar do impacto negativo causado em seu rendimento pelo tratamento antibiótico prévio. Os agentes mais comumente isolados foram o Haemophilus influenzae b, o meningococo e o pneumococo. A

  8. Inoculación bacteriana en el crecimiento y calidad del fruto de cinco variedades de fresa en suelos con pH contrastante

    Directory of Open Access Journals (Sweden)

    José Alberto Ortiz Texon

    2016-04-01

    Full Text Available En un primer experimento se determinó el crecimiento de cinco variedades de fresa en dos suelos con pH contrastante (4.4 y 8.8. La producción de materia seca de la parte aérea, área foliar, volumen radical y concentración de N, P, K en la parte aérea se determinaron 125 días después del trasplante (ddt. Las plantas de todas las variedades cultivadas en pH 4.4 superaron a las cultivadas en pH 8.8 en todas las variables. Las variedades CP-06-15 y Festival fueron las que mejor se adaptaron a las condiciones de pH alcalino. En un segundo experimento se determinó la función de la inoculación con rizobacterias solubilizadoras de fosfatos en la reducción de los efectos negativos del pH alcalino en las variedades de fresa. Dos tipos de inoculación al momento del trasplante fueron comparadas: aplicación con pipeta de precisión e inmersión de las raíces en la suspensión bacteriana; además del testigo (sin inoculación. Se determinó crecimiento de las plantas y la producción y calidad de los frutos. La inoculación bacteriana no tuvo efecto en el crecimiento de la parte aérea y la raíz de las plantas, excepto en la variedad más sensible al pH alcalino (CP-LE-07 inoculada por inmersión de la raíz. También, esta fue la única variedad en la que la inoculación bacteriana aumentó el número de frutos producidos. De acuerdo al promedio de todas las variedades, la inoculación bacteriana, en ambas de sus formas, redujo el número y peso de los frutos producidos.

  9. Etiologia e evolução das meningites bacterianas em centro de pediatria

    OpenAIRE

    Romanelli Roberta M.C.; Araújo Claudete A.; Boucinhas Fernando; Carvalho Inácio R.; Martins Nelson R.L.; Freire Heliane B.M.

    2002-01-01

    Objetivo: determinar a prevalência dos agentes etiológicos das meningites bacterianas em serviço de referência, no atendimento de doenças infecciosas para o estado de Minas Gerais, e verificar a resposta ao tratamento utilizado.Métodos: estudo descritivo em que foram incluídas todas as crianças com diagnóstico provável de meningite, admitidas na instituição no período de junho a novembro/99.Resultados: obteve-se 210 casos de meningite, sendo 111 casos de etiologia bacteriana (52,9%). Destes, ...

  10. La placa bacteriana: conceptos básicos para el higienista bucodental

    OpenAIRE

    Poyato Ferrera, Manuel María; Segura-Egea, Juan J.; Ríos-Santos, J.V.; Bullon, Pedro

    2001-01-01

    La placa bacteriana es el factor etiológico principal de las dos enfermedades bucodentales de mayor prevalencia, la caries y la enfermedad periodontal. El higienista bucodental y colaborador del odontoestomatólogo en la aplicación del programa de control de placa, debe conocer en profundidad la microbiología de la placa bacteriana dental, así como los mecanismos implicados en su patogenicidad cariogénica y periodontal, aspectos que se revisan a continuación. Dental plaque is the main etiol...

  11. Elucidating Flux Regulation of the Fermentation Modes of Lactococcus lactis

    DEFF Research Database (Denmark)

    Chan, Siu Hung Joshua

    The long history of application to the dairy industry has established Lactococcus lactis (L. lactis), the lactic acid bacterium, as one of the most extensively characterized low GC organisms. The relatively simple metabolism of L. lactis has also made it an attractive target for metabolic enginee...... method for combining metabolic flux analysis and elementary mode analysis was developed and applied to analyse a case of amino acid metabolism of L. lactis.......The long history of application to the dairy industry has established Lactococcus lactis (L. lactis), the lactic acid bacterium, as one of the most extensively characterized low GC organisms. The relatively simple metabolism of L. lactis has also made it an attractive target for metabolic...... an important subject for basic research in cellular metabolism because L. lactis exhibits an interesting metabolic shift. Under anaerobic conditions, on fast fermentable sugars, L. lactis produces lactate as the primary product, known as homolactic fermentation but on slowly fermentable sugars, significant...

  12. Plasma mutation breeding of Lactococcus lactis in producing Nisin

    Directory of Open Access Journals (Sweden)

    Shuanli ZHANG

    2015-12-01

    Full Text Available With Nisin-producing Lactococcus lactis as the starting strain, the strain with tolerance to 10 000 IU/mL Nisin is selected on high-concentration Nisin medium. The Nisin titer of the strain is up to 1 680 IU/mL. As the starting strain, the strain is further treated by atmospheric and room temperature plasmas(ARTP and mutant strain for high yield of Nisin is quickly selected with 24 well culture plate. At a survival rate of 3%, the positive mutation rate of the Lactococcus lactis is 273% compared with the starting strain. The results of shake flask culture further confirmed that one positive mutant strains could produce 6 120 IU/mL Nisin.

  13. Chorioamnionitis due to Lactococcus lactis cremoris: A case report

    Directory of Open Access Journals (Sweden)

    F. Azouzi

    2015-07-01

    Full Text Available Lactococcus lactis cremoris is rarely involved in human pathology. A thirty two-year old pregnant woman with premature rupture of membrane history presented with chorioamnionitis due to L. lactis cremoris. She underwent an emergency caesarian section and was treated with antibiotics including the association of amoxicillin and clavulanic acid. She was completely recovered. This is the first case to our knowledge of chorioamnionitis due to this organism.

  14. Chorioamnionitis due to Lactococcus lactis cremoris: A case report

    OpenAIRE

    F. Azouzi; C. Chahed; Marzouk, M.; A. Ferjani; N. Hannechi; M. Fekih; Y. Ben Salem; J. Boukadida

    2015-01-01

    Lactococcus lactis cremoris is rarely involved in human pathology. A thirty two-year old pregnant woman with premature rupture of membrane history presented with chorioamnionitis due to L. lactis cremoris. She underwent an emergency caesarian section and was treated with antibiotics including the association of amoxicillin and clavulanic acid. She was completely recovered. This is the first case to our knowledge of chorioamnionitis due to this organism.

  15. Lactococcus garvieae Endocarditis on a Prosthetic Biological Aortic Valve.

    Science.gov (United States)

    Tsur, A; Slutzki, T; Flusser, D

    2015-09-01

    Lactococcus garvieae (LG) endocarditis is a rare disease in humans. There are only about 16 reported cases in the world. We report a 76-year-old male patient with LG endocarditis. In depth interview with the patient revealed that 2 weeks prior to admission, he had eaten sushi containing raw fish. Unlike many of the other infections reported, which were on a native mitral valve, our patient's vegetation was on a prosthetic aortic valve.

  16. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    ROMERO MAGALLY

    2009-08-01

    Full Text Available RESUMEN

    El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y socioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como “vulnerable” y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 106 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >105 ufc mL-1 . El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.

    Palabras clave: Strombus gigas, Caracol pala, Bacteria, Región intergénica 16S-23S, rDNA 16S.

    ABSTRACT

    The Queen Conch, Strombus gigas (Strombidae, is a species of great ecological and socioeconomic importance in the Caribbean area of Colombia

  17. Participación del factor transcripcional NF-KB en la endocitosis de staphylococcus aureus en células de epitelio marino bovino estimuladas por prolactina

    OpenAIRE

    Lara Zárate, Leticia

    2011-01-01

    La mastitis bovina es considerada una de las enfermedades de mayor relevancia en la ganadería lechera a nivel mundial. Esta patología se caracteriza por una respuesta inflamatoria de la glándula mamaria de origen multifactorial, ocasionada principalmente por infecciones bacterianas.

  18. Caracterización de pacientes con bronconeumonía bacteriana asociada a la ventilación artificial mecánica

    Directory of Open Access Journals (Sweden)

    Danilo Eranio Utra Cardoso

    2015-06-01

    Full Text Available Fundamento: las neumonías nosocomiales constituyen hoy en día un problema de salud a nivel mundial. En las unidades de cuidados intensivos de las instituciones hospitalarias ingresa un elevado número de pacientes que requieren ventilación artificial mecánica, factor de riesgo asociado a este tipo de infecciones. Objetivo: caracterizar a los pacientes con neumonías bacterianas asociadas a la ventilación artificial mecánica, ingresados en la sala de cuidados intensivos del Hospital General Docente “Dr. Ernesto Guevara de la Serna”, Las Tunas, Cuba; durante el año 2012. Métodos: se realizó un estudio descriptivo, retrospectivo, en los pacientes (262 ingresados en esa unidad, en el período de enero a diciembre de 2012. La muestra quedó conformada por los 173 pacientes complicados por neumonías bacterianas. Los datos fueron tomados de los expedientes clínicos. Se midieron las variables: grupos de edad, manifestaciones radiológicas, gérmenes más frecuentes y modalidades ventilatorias empleadas. Resultados: predominaron los pacientes mayores de 60 años, para un 41 %, seguido por el grupo de 50 a 59 años con 26,5 %. El germen más frecuente fue el bacilo no fermentador para el 76,6 %; la modalidad ventilatoria de volumen control fue la más utilizada, en 75 pacientes (43,6 %; el trastorno hidromineral se presentó en el 41 % de los casos, todos con tendencia a la hipokaliemia, que dio lugar a un difícil destete; los síntomas radiológicos anatomoclínicos fueron los relacionados con las neumonías a focos diseminados con 95 pacientes para 54,9 %. Conclusiones: se logró caracterizar a los pacientes con neumonías bacterianas asociadas a la ventilación artificial mecánica.

  19. Cumplimiento de las recomendaciones internacionales en la lucha contra las resistencias bacterianas

    DEFF Research Database (Denmark)

    Malo, Sara; Jose Rabanaque, Mara; Bjerrum, Lars

    2016-01-01

    Introducción: El aumento de la resistencia a antibióticosrepresenta una amenaza para la salud pública al poner en riesgoel tratamiento futuro de las infecciones bacterianas. Este estudiotiene como objetivo describir el cumplimiento de las recomendaciones del Advisory Group on Integrated Surveilla...

  20. Complete genome sequence of the prototype lactic acid bacterium Lactococcus lactis subsp cremoris MG1363

    NARCIS (Netherlands)

    Wegmann, Udo; O'Connell-Motherwy, Mary; Zomer, Aldert; Buist, Girbe; Shearman, Claire; Canchaya, Carlos; Ventura, Marco; Goesmann, Alexander; Gasson, Michael J.; Kuipers, Oscar P.; van Sinderen, Douwe; Kok, Jan

    2007-01-01

    Lactococcus lactis is of great importance for the nutrition of hundreds of millions of people worldwide. This paper describes the genome sequence of Lactococcus lactis subsp. cremoris MG1363, the lactococcal strain most intensively studied throughout the world. The 2,529,478-bp genome contains 81 ps

  1. QUIMIOTAXIS BACTERIANA Y FLAVONOIDES: PERSPECTIVAS PARA EL USO DE PROBIOTICOS.

    OpenAIRE

    Mónica Marcela Galicia-Jiménez; Carlos Sandoval-Castro; Rafael Rojas-Herrera; Héctor Magaña-Sevilla

    2011-01-01

    La aplicación de diversas dietas se han enfocado en buscar mayor producción en los rumiantes variando el alimento del animal, afectando así la población microbiana ruminal, sin embargo, la eficacia en la producción del rumiante ha sido reportada de manera inconsistente. Por otro lado, se han realizado estudios de metabolitos secundarios secretados por plantas y se ha visto que tienen una función de atrayente o repelente en la interacción planta-microorganismo. Por lo que nuestro objetivo es i...

  2. Sobre la resistencia bacteriana hacia antibióticos de acción bactericida y bacteriostática

    Directory of Open Access Journals (Sweden)

    Jhoana P. Romero L.

    2014-06-01

    Full Text Available En este artículo se formula un modelo matemático simple que describe la interacción entre bacterias sensibles y resistentes a múltiples antibióticos de acción bactericida y bacteriostática de forma simultánea, en el supuesto de que la adquisición de resistencia bacteriana se da a través de mutaciones espontáneas y adquiridas por la exposición a diferentes antibióticos. El análisis cualitativo revela la existencia de un equilibrio libre de bacterias, un equilibrio solo con bacterias resistentes y un equilibrio endémico donde coexisten ambas poblaciones de bacterias. Abstract. In this work we formulate a simple mathematical model that describes the population dynamics of bacteria exposed simultaneously to multiple bactericidal and bacteriostatic antibiotics, assuming that resistance is acquired through mutations due to antibiotic exposure. Qualitative analysis reveals the existence of a free-bacteria equilibrium, resistant-bacteria equilibrium and an endemic equilibrium where both bacteria coexist.

  3. Estudio de la interacción de bacterias implicadas en la formulación de placa dentro-bacteriana con superficies de titanio comercialmente puro in vitro y su asociación con la peri-implantitis.

    OpenAIRE

    Rodríguez Hernández, Ana Guadalupe

    2009-01-01

    La peri-implantitis puede poner en riesgo la integridad funcional de un implante dental, ya que dependiendo de la severidad del daño, éste puede ocasionar la pérdida irremediable del implante. Dicho padecimiento está asociado directamente con la formación de la placa dento-bacteriana sobre la superficie del implante.En este trabajo de tesis se estudiarón, por un lado las propiedades de superficie de 6 tipos diferentes de tratamientos utilizados en implantes dentales (tales como: la rugosidad,...

  4. Efeitos do pneumoperitônio e da laparotomia na populaçao bacteriana intra-peritoneal e na ocorrencia de bacteremia em ratos wistar com peritonite fecal

    OpenAIRE

    1999-01-01

    Resumo: Os objetivos do presente estudo foram comparar as populações bacterianas intra-peritoneais e os níveis de bacteremia, em ratos induzidos com peritonite fecal e pneumoperitônio ou laparotomia, com irrigação da cavidade abdominal. Foram utilizados 60 ratos Wistar machos, pesando entre 276 e 290g, divididos em 6 grupos com 10 animais cada. A indução da peritonite foi feita pela inoculação intra-peritoneal de 0,5ml de suspensão fecal humana. O pneumoperitônio foi realizado por 60 minutos,...

  5. Medición de cambios cuantitativos de la microbiota subgingival posterior a la remoción de placa bacteriana supragingival Measurement of quantitative changes of the microbiota subgingival after to removal of bacterial plaque supragingival

    OpenAIRE

    C. Godoy; Melej,C; Silva, N

    2010-01-01

    Uno de los campos de interés en el estudio de la microbiología periodontal para muchos investigadores ha sido identificar si es posible que los microorganismos responsables del origen y progresión de la enfermedad periodontal que habitan sobre el margen gingival (supragingival) y bajo este (subgingival) tengan una relación directa que permita mantener interacciones influyentes en el crecimiento y desarrollo de las diferentes especies bacterianas que habitan en los tejidos periodontales. Por l...

  6. Efeito de probiótico comercial sobre o desempenho de pós-larvas de Litopenaeus vannamei em sistema de biofloco e sua influência sobre as comunidades bacteriana e fitoplanctônica.

    OpenAIRE

    Maria Gabriela Padilha Ferreira

    2012-01-01

    A adição de probióticos nas fazendas de camarão tem aumentado como alternativa ao uso de antibióticos e devido à demanda por uma aquicultura mais sustentável. Eles tem melhorado o desempenho e a saúde do hospedeiro e a qualidade da água e do solo, atuando como agentes de biocontrole e biorremediação nos sistemas de cultivo. O presente estudo investigou os efeitos de diferentes concentrações de um probiótico comercial na qualidade da água, desempenho zootécnico, comunidade bacteriana e fitopla...

  7. Contagem de morfotipos de Mobiluncus sp e concentração de leucócitos em esfregaços vaginais de pacientes com vaginose bacteriana

    Directory of Open Access Journals (Sweden)

    Eleutério Junior José

    2004-01-01

    Full Text Available OBJETIVOS: pesquisar em casos de vaginose bacteriana a presença de bacilos curvos, sugerindo Mobiluncus, e de leucocitose em esfregaços vaginais corados por Gram e Papanicolaou. MÉTODOS: duzentos e cinco pacientes com diagnóstico de vaginose bacteriana pelos Critérios de Amsel foram incluídas e avaliadas clinicamente por um dos autores (JEJ. Os esfregaços vaginais foram corados pelo método de Papanicolaou e avaliados pela técnica de Gram. Nos esfregaços de Gram foram estudados o escore de Nugent e a presença de bacilos curvos. Nos esfregaços de Papanicolaou foi avaliada a presença de bacilos curvos e de leucócitos. Os dados foram analisados usando Prism 3.0® com intervalo de confiança de 95%, usando teste exato de Fisher pelo método modificado de Wald. RESULTADOS: nos esfregaços de Papanicolaou, bacilos curvos estiveram presentes em 51,7% das vezes. O número de leucócitos variou, embora a presença de poucos leucócitos tenha sido mais freqüente. Nos esfregaços de Gram, bacilos curvos foram observados em 46,8% e o escore de Nugent foi 8 em 48,3% dos casos. O achado de Mobiluncus sp pelos dois métodos ocorreu em 82%. Na presença de bacilos curvos, maior número de leucócitos foi observado em 57,5% dos casos (p <0,0001 e quando o escore de Nugent foi de 9 e 10, a leucocitose ocorreu em 25,6 e 37,2% das vezes, respectivamente. CONCLUSÕES: bacilos curvos são observados, morfologicamente, em cerca de 52% dos casos de vaginose bacteriana. Leucocitose é mais observada na presença de Mobiluncus sp e em casos com escores de Nugent mais altos.

  8. Importancia clínica de la translocación bacteriana Clinical importance of bacterial translocation

    Directory of Open Access Journals (Sweden)

    A. García de Lorenzo y Mateos

    2007-05-01

    Full Text Available El tracto gastrointestinal está colonizado por una inmensa cantidad de microorganismos, a los que denominamos flora intestinal. Aunque el intestino proporciona una barrera funcional entre estos organismos y el huésped, la traslocación bacteriana no es un evento infrecuente entre las personas sanas. Sin embrago, en los pacientes críticamente enfermos, que son portadores de diferentes entidades nosológicas, la translocación bacteriana puede condicionar infecciones e incrementos en la morbi-mortalidad. Varios son los mecanismos propuestos para explicar la etiología, génesis y vías de esta entidad y, frecuentemente, los resultados de las investigaciones realizadas tanto in vitro como en animales de experimentación son controvertidos y de difícil aplicación a los humanos. Muchas enfermedades se han relacionado o están implicadas en el fenómeno de translocación pero desgraciadamente el sumatorio de estudios metodológicamente insuficientes, poblaciones reducidas y resultados conflictivos dejan, hoy en día, muchas preguntas abiertas y otras sin respuesta lógica. Esta problemática también se refleja a la hora de estudiar y valorar las diferentes estrategias terapéuticas utilizadas así como los métodos empleados para detectar la traslocación.The gastrointestinal tract is colonized by a huge number of microorganisms that we call intestinal flora. Although the bowel provides a functional barrier between these organisms and the host, bacterial translocation is not an infrequent event in healthy people. However, in critically ill patients, carriers of different morbid entities, bacterial translocation may favor infections and increased morbimortality. There are several proposed mechanisms explaining the etiology, genesis, and ways for this entity, and frequently the results from both in vitro and animal experimental investigations are controversial and difficult to apply to humans. Many diseases have been linked or are implicated in

  9. Molecular characterization of ruminal bacterial diversity in vitro = Caracterização molecular da diversidade bacteriana ruminal in vitro

    Directory of Open Access Journals (Sweden)

    Humberto Maciel França Madeira

    2008-04-01

    Full Text Available PCR analysis is a sensitive and specific tool to detect and monitormicroorganisms in complex environmental samples. The amplification of 16S ribosomal DNA sequences followed by gel electrophoresis under denaturing gradient (DGGE has been a powerful technique to genetically evaluate microbial ecosystems. Changes in rumenmicrobial populations were investigated in vitro using a basal diet with different lipid sources. PCRs were performed with two different sets of primers in order to amplify 16S rRNA sequences, and the amplified fragments were submitted to DGGE analysis. The findings presented in this study show that distinct microbial communities were present in each treatment. The presence of soybean oil seems to maximize growth of bacterial population, whereas fish oil appears to reduce growth. We demonstrated the successful application of molecular ecological techniques to analyze the structure and composition of bacterial communities in rumen ecosystems.A análise por PCR fornece um meio sensível e específico para detectar e monitorar microrganismos em amostras ambientais complexas. Desde sua aplicação inicial, o DNA ribossomal 16S (rRNA em eletroforese com gel com gradiente desnaturante (DGGE, tem sido uma técnica atrativa para a ecologia molecular microbiana. Foram investigadas mudanças na população microbiana no rúmen, a partir de alterações da dieta com tratamentos in vitro de diferentes fontes de lipídeos. ODGGE foi testado com dois pares de primers para o rRNA 16S. O uso do fragmento de 200 pb gerou um perfil de bandas mais discriminatório, mostrando que diferentes comunidades microbianas estavam presentes entre os tratamentos in vitro analisados. A presença de óleo de sojapotencializou o crescimento da população bacteriana, enquanto que óleo de peixe parece ter reduzido esse crescimento. Foi possível demonstrar o sucesso da aplicação de técnicas moleculares para analisar a estrutura e a composição de comunidades

  10. Fermentation Tecniques and Applications of Bacterial Cellulose: a Review Técnicas de fermentación y aplicaciones de la celulosa bacteriana: una revisión

    Directory of Open Access Journals (Sweden)

    Luz Dary Carreño Pineda

    2012-12-01

    Full Text Available Bacterial cellulose is a polymer obtained by fermentation with microorganismsfrom Acetobacter, Rhizobium, Agrobacterium and Sarcina genera. Amongthem, Acetobacter xylinum is the most efficient specie. This polymer hasthe same chemical composition of plant cellulose, but its conformation andphysicochemical properties are different, making it attractive for several applications, especially in the areas of food, separation processes, catalysis andhealth, due to its biocompatibility. However, the main problem is the production in mass that is constrained by low yield. It is therefore necessaryto develop some alternatives. This paper presents a review about synthesis,production, properties and principal applications of bacterial cellulose, as wellas some alternatives to reduce the difficulties for process scaling.La celulosa bacteriana es un polímero obtenido por fermentación con microrganismosde los géneros Acetobacter, Rhizobium, Agrobacterium y Sarcina, delas cuales la especie más eficiente es la Acetobacter Xylinum. Este polímero presenta la misma estructura química de la celulosa de origen vegetal, pero difiereen su conformación y propiedades fisicoquímicas, lo que lo hace atractivo para diversas aplicaciones, especialmente en las áreas de alimentos, procesosde separación, catálisis y en medicina, gracias a su biocompatibilidad. Sin embargo, el principal problema es la producción a gran escala limitada por losbajos rendimientos, lo que genera la necesidad de desarrollar alternativas que permitan disminuir o eliminar las causas de esta limitación. En este artículo se hace una revisión acerca de la síntesis, producción, propiedades y principales aplicaciones de la celulosa bacteriana, así como de algunas alternativas estudiadas para disminuir los inconvenientes en el escalamiento del proceso.

  11. PATOGENICIDAD BACTERIANA EN MAÍZ (ZEA MAYS

    Directory of Open Access Journals (Sweden)

    Rocío Pérez-y-Terrón

    2012-01-01

    Full Text Available El maíz es un grano de consumo mundial para alimento tanto humano como animal. México se encuentra en el séptimo lugar de la producción, China y Estados Unidos son los principales consumidores. Zea mays pertenece a la familia de las gramíneas y tiene producción anual. La planta se puede ver afectada por plagas principalmente de diferentes especies de insectos. Puede también desarrollar enfermedad debida a hongos y virus, así como a bacterias patogénicas. Dentro de estas la causada por organismos del género Pantoea. P. stewartii se sabe que tiene genes como cps que codifican para la producción de exopolisacarido sterwatan controlada por un mecanismo de quórum sensing, y hrp para el sistema de secreción tipo III involucrados en la patogenicidad de la bacteria.

  12. PATOGENICIDAD BACTERIANA EN MAÍZ (ZEA MAYS)

    OpenAIRE

    Rocío Pérez-y-Terrón; Julio César Carmona Díaz; Jorge Alejandro Cebada Ruíz; José Antonio Munive Hernández

    2012-01-01

    El maíz es un grano de consumo mundial para alimento tanto humano como animal. México se encuentra en el séptimo lugar de la producción, China y Estados Unidos son los principales consumidores. Zea mays pertenece a la familia de las gramíneas y tiene producción anual. La planta se puede ver afectada por plagas principalmente de diferentes especies de insectos. Puede también desarrollar enfermedad debida a hongos y virus, así como a bacterias patogénicas. Dentro de estas la causada por organis...

  13. Associação da Vaginose Bacteriana com o Parto Prematuro Espontâneo Association of Bacterial Vaginosis with Spontaneous Preterm Delivery

    Directory of Open Access Journals (Sweden)

    Mário Henrique Burlacchini de Carvalho

    2001-09-01

    Full Text Available Objetivo: relacionar a presença de vaginose bacteriana em gestantes com a ocorrência de parto prematuro espontâneo. Método: foram estudadas 611 gestantes do serviço pré-natal da Clínica Obstétrica do HCFMUSP. Foram incluídas gestantes com idade gestacional confirmada por ultra-sonografia no primeiro trimestre de gestação ou duas ultra-sonografias até a 20ª semana quando havia discordância da idade gestacional no primeiro exame. Os partos prematuros eletivos foram excluídos. A pesquisa da vaginose foi realizada na 23ª ou 24ª semana de gestação por meio da técnica de coloração de Gram. O pH vaginal foi pesquisado utilizando-se fita de pH Universal 0-14 produzida pela Merck. O conteúdo vaginal foi coletado com a paciente em posição ginecológica, utilizando-se espéculo não-lubrificado. O pH foi medido na parede lateral da vagina e o conteúdo para Gram foi coletado do fundo de saco vaginal utilizando-se de cotonete estéril. Resultado: das 611 gestantes envolvidas inicialmente no estudo, foram obtidos os resultados do parto em 541. A vaginose bacteriana foi diagnosticada por bacterioscopia em 19% dos casos. No grupo de gestantes com vaginose, 9,7% (10/103 evoluíram com parto prematuro, contra apenas 3,2% (14/438 no grupo negativo (p=0,008. A sensibilidade da bacterioscopia positiva para vaginose bacteriana para predição do parto prematuro foi de 41,7%, a especificidade de 82%, a acurácia de 80,2%, com taxa de falso-positivos de 18% e risco relativo de 1,8. Conclusão: a vaginose bacteriana diagnosticada pelo Gram do conteúdo vaginal representa fator de risco para o parto prematuro, com risco relativo de 1,8.Purpose: to evaluate the relationship between bacterial vaginosis (BV and spontaneous preterm delivery. Method: a total of 611 pregnant women from the general antenatal clinic of the "Clínica Obstétrica do Hospital das Clínicas da Universidade de São Paulo" were enrolled in this study. All pregnancies were

  14. Resistencia bacteriana de cultivos de orina en un hospital oncológico:seguimiento a diez años

    Directory of Open Access Journals (Sweden)

    Consuelo Velázquez-Acosta

    2016-07-01

    Full Text Available Objetivo. Describir los patrones de resistencia bacteriana en cultivos de orina de pacientes de un hospital oncológico en la Ciudad de México, de 2004 a 2013. Material y métodos. Se obtuvo el porcentaje de susceptibilidad para diferentes antibióticos, describiendo por separado las bacterias multidrogorresistentes (MDR. Se analizaron por separado las cepas obtenidas de pacientes hospitalizados de las de la comunidad. Resultados. Se realizaron 51 202 cultivos, de los cuales se identificaron 14 480 bacterias (28.3%. De éstas, se reportaron 11 427 Gram negativos (78.9%; 2 080 Gram positivos (14.4%; y 973 (6.6% levaduras. Escherichia coli fue el principal microorganismo aislado (56.1%; 24% de las cepas de la comunidad y 66% de las nosocomiales fueron productoras de beta-lactamasas de espectro extendido (BLEE. Klebsiella pneumoniae se identificó en 705 cultivos (4.8%, 115 de los cuales fueron BLEE (16%: 13.1% de la comunidad y 29.8% nosocomiales. Pseudomonas aeruginosa se identificó en 593 cultivos (4.1%: 9% de la comunidad y 51% nosocomiales. Conclusiones. Las cepas MDR son mucho más frecuentes en muestras de origen nosocomial. Es prioritario intensificar el uso racional de antibióticos en la comunidad y el programa de desescalamiento de antimicrobianos en el hospital.   DOI: http://dx.doi.org/10.21149/spm.v58i4.8025

  15. A resistência bacteriana no contexto da infecção hospitalar

    OpenAIRE

    Neusa Santos de Queiroz

    2004-01-01

    Este artículo aporta algunos aspectos sobre el impacto de la resistencia bacteriana en el contexto de la infección hospitalar. Alerta sobre el papel importante de los profissionais de la salud para el control de la infección hospitalar y del grave problema del uso indiscriminado de los antibióticos que han generado una presión selectiva sobre las bacterias del ambiente hospitalario tornándolas multiresistentes

  16. A resistência bacteriana no contexto da infecção hospitalar

    Directory of Open Access Journals (Sweden)

    Neusa Santos de Queiroz

    2004-01-01

    Full Text Available Este artículo aporta algunos aspectos sobre el impacto de la resistencia bacteriana en el contexto de la infección hospitalar. Alerta sobre el papel importante de los profissionais de la salud para el control de la infección hospitalar y del grave problema del uso indiscriminado de los antibióticos que han generado una presión selectiva sobre las bacterias del ambiente hospitalario tornándolas multiresistentes

  17. Potential aquaculture probiont Lactococcus lactis TW34 produces nisin Z and inhibits the fish pathogen Lactococcus garvieae.

    Science.gov (United States)

    Sequeiros, Cynthia; Garcés, Marisa E; Vallejo, Marisol; Marguet, Emilio R; Olivera, Nelda L

    2015-04-01

    Bacteriocin-producing Lactococcus lactis TW34 was isolated from marine fish. TW34 bacteriocin inhibited the growth of the fish pathogen Lactococcus garvieae at 5 AU/ml (minimum inhibitory concentration), whereas the minimum bactericidal concentration was 10 AU/ml. Addition of TW34 bacteriocin to L. garvieae cultures resulted in a decrease of six orders of magnitude of viable cells counts demonstrating a bactericidal mode of action. The direct detection of the bacteriocin activity by Tricine-SDS-PAGE showed an active peptide with a molecular mass ca. 4.5 kDa. The analysis by MALDI-TOF-MS detected a strong signal at m/z 2,351.2 that corresponded to the nisin leader peptide mass without the initiating methionine, whose sequence STKDFNLDLVSVSKKDSGASPR was confirmed by MS/MS. Sequence analysis of nisin structural gene confirmed that L. lactis TW34 was a nisin Z producer. This nisin Z-producing strain with probiotic properties might be considered as an alternative in the prevention of lactococcosis, a global disease in aquaculture systems.

  18. Bacterial diversity in the sediments of a temperate artificial lake, Rapel reservoir Diversidad bacteriana en sedimentos de un lago artificial temperado, embalse Rapel

    Directory of Open Access Journals (Sweden)

    CRISTINA DORADOR

    2007-06-01

    Full Text Available Rapel reservoir is an eutrophic system in Chile that has undergone a series of anthropogenic impacts in recent decades. To provide a better understanding of the processes occurring in the reservoir, we examined bacterial composition from surface sediments using traditional microbiology techniques and molecular biology tools. Our results showed significant temporal variation in the physical and chemical composition of the water column, but no depth-related differences during the study period. To detect temporal changes in bacterial composition, cultivable heterotrophic bacteria, heterotrophic iron oxidizing bacteria, and sulfate-reducing bacteria were extracted from the surface sediments and their concentration measured. Microbial diversity in sediments was represented by closest relatives of eight different bacterial phyla. The most frequently recovered phylotypes in the clone library of 16S rDNA were related to sulfate-reducing bacteria belong to the Deltaproteobacteria groupEl embalse Rapel es un sistema eutrófico en Chile que ha experimentado diversos impactos antropogénicos en las últimas décadas. Para conocer mejor los posibles procesos que ocurren en el embalse, la composición bacteriana fue estudiada en la zona superficial de los sedimentos utilizando técnicas microbiológicas tradicionales y herramientas de biología molecular. Nuestros resultados mostraron variación temporal significativa en la composición física y química del agua, no encontrándose diferencias de las variables medidas entre superficie y fondo en la columna de agua durante el período de estudio. Para detectar cambios temporales en la concentración y composición bacteriana, se midieron bacterias heterótrofas, heterótrofas oxidantes de fierro y bacterias reductoras de sulfato extraídas de la superficie de los sedimentos. La diversidad bacteriana en los sedimentos estuvo representada por 8 diferentes Phyla del dominio Bacteria. Los filotipos m

  19. Aerobic bacterial microbiota in stomoxys calcitrans: preliminary studies in Brazil Microbiota bacteriana aeróbica em Stomoxys calcitrans: estudos preliminares no Brasil

    Directory of Open Access Journals (Sweden)

    Bruno G. de Castro

    2007-12-01

    Full Text Available The stable fly, Stomoxys calcitrans, has a great importance in medical and veterinary health due to its feeding and reproductive habits, which can disseminate some pathogenic agents among hosts even at long distances. This study aimed to describe, for the first time in Brazil, the bacterial microbiota in segments of the stable fly. Bacterial species were isolated from three different segments (cuticle, mouth parts and abdominal alimentary tract of the stable fly. Twenty dairy farms were visited in four municipalities: Barra Mansa, Quatis, Resende and Rio Claro in the State of Rio de Janeiro in order to collect 20 flies in each site. Dissection of the flies and procedures of isolation and identification of bacterial species were performed. A total of 161 colonies of 33 distinct species were isolated, such as Escherichia coli, Staphylococcus aureus, and S. intermedius. Stomoxys calcitrans may harbor bacterial agents on their cuticle, mouth parts and abdominal alimentary tract and these bacteria may be pathogenic to their hosts.A mosca dos estábulos, Stomoxys calcitrans, possui grande importância médica e veterinária devido a seus hábitos alimentares e reprodutivos, visto que pode disseminar agentes patogênicos para hospedeiros, mesmo a longas distâncias. Esse estudo teve por objetivo, pela primeira vez no Brasil, descrever a microbiota bacteriana de segmentos da mosca dos estábulos. As espécies bacterianas foram isoladas de três diferentes segmentos (superfície externa, aparelho bucal e trato digestivo abdominal de S. calcitrans. Foram visitadas 20 fazendas leiteiras em quatro municípios: Barra Mansa, Quatis, Resende e Rio Claro no Estado do Rio de Janeiro para coletar 20 moscas em cada uma delas. A dissecção das moscas e os procedimentos de isolamento e identificação bacteriana foram realizados. Um total de 161 colônias de 33 espécies distintas foi isolado, dentre elas Escherichia coli, Staphylococcus aureus e S. intermedius

  20. USO DE PATRONES DE DIFRACCIÓN DE LUZ LÁSER Y ANÁLISIS DE IMAGENES PARA DIFERENCIACIÓN DE TRES TIPOS DE COLONIAS BACTERIANAS

    Directory of Open Access Journals (Sweden)

    GLORIA ARANGO

    2013-01-01

    Full Text Available La diferenciación rápida de colonias bacterianas es esencial en muchos campos industriales, científicos y de salud humana y animal. Generalmente esa diferenciación se logra por técnicas microscópicas, bioquímicas o genéticas muy elaboradas que requieren tiempo y entrenamiento. En este estudio se utilizaron técnicas de análisis de imágenes sobre patrones de difracción de luz láser para evaluar su sensibilidad en la diferenciación de colonias bacterianas. Adicionalmente se estudió el efecto del tiempo de crecimiento de las colonias en la generación de estos patrones y se determinó la influencia de la cantidad de medio de cultivo en la difracción de luz láser. Los patrones de difracción del láser se obtuvieron sobre cultivos puros de cinco aislamientos bacterianos B1, B2, B3, B2Ca y B2Cb. En la primera prueba de diferenciación se utilizaron colonias de B2, B3, B2Ca. En el estudio del efecto del tiempo de crecimiento sobre patrones de difracción, las bacterias B1 y B2Cb con uno o dos días de crecimiento. Finalmente, el efecto de la cantidad de medio de cultivo en la difracción de la luz, se evaluó en una prueba en cajas petri con 10, 15 o 20 ml de medio de cultivo estéril sin colonias de bacterias. Mediante un análisis de escalado multidimensional realizado con los parámetros de textura extraídos de las imágenes de los patrones, se obtuvo un agrupamiento adecuado de los patrones asociados a las colonias de cada bacteria evaluada, lo cual indicó que las colonias bacterianas se pueden diferenciar por sus patrones de difracción. Adicionalmente se encontró que no hay variaciones significativas en los patrones de difracción obtenidos de dos aislamientos bacterianos en dos tiempos de crecimiento. El espesor del medio de cultivo afectó la difracción del haz de luz pues patrones obtenidos de cajas petri con 10 ml se separan completamente de los patrones obtenidos con 15 y 20 ml, aunque no hay diferencias entre los dos

  1. Localization and accessibility of antigenic sites of the extracellular serine proteinase of Lactococcus lactis

    NARCIS (Netherlands)

    Laan, Harm; Kok, Jan; Haandrikman, Alfred J.; Venema, Gerhardus; Konings, Wilhelmus

    1992-01-01

    Lactococcus lactis strains produce an extracellular subtilisin-related serine proteinase in which immunologically different components can be distinguished. Monoclonal antibodies specific for the different proteinase components have been raised and their epitopes were identified. By Western-blot ana

  2. Physiological Adaptation of the Bacterium Lactococcus lactis in Response to the Production of Human CFTR

    NARCIS (Netherlands)

    Steen, Anton; Wiederhold, Elena; Gandhi, Tejas; Breitling, Rainer; Slotboom, Dirk Jan

    2011-01-01

    Biochemical and biophysical characterization of CFTR (the cystic fibrosis transmembrane conductance regulator) is thwarted by difficulties to obtain sufficient quantities of correctly folded and functional protein. Here we have produced human CFTR in the prokaryotic expression host Lactococcus lacti

  3. MOSAIC, BACTERIAL SPOT AND BLIGHT IN PEPPER-REVIEW MOSAICO, PÚSTULA BACTERIANA E REQUEIMA DO PIMENTÃO – REVISÃO BIBLIOGRÁFICA

    Directory of Open Access Journals (Sweden)

    Francisco J. B. Reifschneider

    2007-09-01

    Full Text Available

    A review about sintomatology, etiology, epidemiology, control, inoculation and evaluation of mosaic (potato virus Y, bacterial spot (Xanthomonas campestris pv. vesicatoria and blight (Phytophthora capsici is presented.

    Aspectos relacionados à sintomatologia, etiologia, epidemiologia, controle, inoculação e avaliação de mosaico (vírus Y da batata, pústula bacteriana (Xanthomonas campestris pv. vesicatoria e requeima (Phytophthora capsici são abordados em revisão bibliográfica. Em diversos países, o mosaico do pimentão (Capsicum annuun L. é enfermidade importante (LANGE & HAMMI, 1977; WIJS, 1980; NAGAI, 1984 e em algumas localidades foi considerado o problema mais sério da cultura (LOCKHART & FISCHER, 1974. Dentre as bacterioses que afetam o pimentão, a que mais se destaca é a pústula bacteriana (KIMURA, 1984. Também a requeima ou murcha é problema em diversas regiões produtoras (KIMBLE & GROGANK 1960; BAZAN DE SEGURA, 1962; MATTA & GARIBALDI, 1972; ERHAD & HILLE, 1975; MATSUOKA ei alii, 1984. Essa revisão pretende abordar cada uma destas doenças, abrangendo aspectos desde sintomatologia até controle, de utilidade na elaboração de projetos de pesquisa que visem ao controle por resistência genética.

  4. POBLACIONES BACTERIANAS NATIVAS: ALTERNATIVA SUSTENTABLE PARA LA AGRICULTURA

    OpenAIRE

    Lina Hernández-Flores; J. Antonio Munive-Hernández; Engelberto Sandoval-Castro; Daniel Martínez-Carrera; Ma. Carmen Villegas-Hernández

    2012-01-01

    La producción agrícola moderna requiere gran cantidad de agroquímicos derivados del petróleo, por lo que su producción y uso contaminan el ambiente, además de generar daños en la salud de los seres vivos. Una alternativa para mantener un nivel rentable de producción, con un menor uso de agroquímicos, y enfocando la agricultura hacia un manejo sustentable, es la aplicación de microorganismos fijadores de nitrógeno. De esta forma, se busca implementar alternativas que permitan reducir los costo...

  5. Experimental determination of control of glycolysis in Lactococcus lactis

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Andersen, Heidi Winterberg; Solem, Christian

    2002-01-01

    and below the wild-type level. We review a genetic approach that is well suited for both Metabolic Optimization and Metabolic Control Analysis and studies on the importance of a number of glycolytic enzymes for metabolic fluxes in Lactococcus lactis. The glycolytic enzymes phosphofructokinase (PFK......The understanding of control of metabolic processes requires quantitative studies of the importance of the different enzymatic steps for the magnitude of metabolic fluxes and metabolite concentrations. An important element in such studies is the modulation of enzyme activities in small steps above......), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), pyruvate kinase (PYK) and lactate dehydrogenase (LDH) are shown to have no significant control on the glycolytic flux in exponentially growing cells of L. lactis MG1363. Introduction of an uncoupled ATPase activity results in uncoupling of glycolysis from biomass...

  6. Transforming Lactococcus lactis into a microbial cell factory

    DEFF Research Database (Denmark)

    Petersen, Kia Vest

    . To simplify further analysis arcA encoding the arginine deiminase was deleted, thus eliminating the arginine catabolism. We found that in L. lactis KF147 xylose is metabolized through two pathways namely the phosphoketolase pathway and the non-oxidative part of the pentose phosphate pathway. The only products...... the potential of Lactococcus lactis as a platform organism for production of biofuels and-chemicals with a focus on characterization and optimization of the xylose metabolism. The plant isolate L. lactis KF147 was selected as the potential platform organism due to its natural ability to utilize both the pentose...... for the next round of integration. The xylose metabolism in L. lactis KF147 was characterized in a defined medium supplemented with 0.2%, 1% or 3% (w/v) xylose. The defined medium contains free arginine, and it was found that L. lactis KF147 co-metabolizes the arginine through the arginine deiminase pathway...

  7. Infective endocarditis with Lactococcus garvieae in Japan: a case report

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    Isonuma Hiroshi

    2011-08-01

    Full Text Available Abstract Introduction Lactococcus garvieae is a well-recognized fish pathogen, and it is considered a rare pathogen with low virulence in human infection. We describe the 11th case of L. garvieae infective endocarditis reported in the literature, and the first reported case in Japan. Case presentation We report a case of a 55-year-old Japanese woman who had native valve endocarditis with L. garvieae. The case was complicated by renal infarction, cerebral infarction, and mycotic aneurysms. After anti-microbial treatment, she was discharged from the hospital and is now well while being monitored in the out-patient clinic. Conclusion We encountered a case of L. garvieae endocarditis that occurred in a native valve of a healthy woman. The 16S ribosomal RNA gene sequencing was useful for the identification of this pathogen. Although infective endocarditis with L. garvieae is uncommon, it is possible to treat high virulence clinically.

  8. Infecções bacterianas pioram o prognóstico da hepatite alcoólica Alcoholic hepatitis: bad prognosis due to concomitant bacterial infections

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    Edna Strauss

    2004-06-01

    Full Text Available As infecções bacterianas cursam com altos índices de morbilidade e mortalidade na cirrose hepática. O objetivo do nosso trabalho foi avaliar se também na hepatite alcoólica as infecções bacterianas são fatores de mau prognóstico. Na avaliação retrospectiva de 681 pacientes hospitalizados em um único centro, por período de 6 anos, foram bem documentados 52 (7,5% casos de hepatite alcoólica, sendo 73,1% com biópsia hepática para análise histopatológica e os restantes por diagnóstico clínico-bioquímico. Houve predomínio do sexo masculino (relação 3,3:1,0, com idade média de 40 anos e ingestão média de etanol puro de 193g/dia por mais de 3 anos. As principais complicações foram: encefalopatia hepática (n=5, insuficiência renal (n=4 e hemorragia digestiva alta (n=3. Houve infecção bacteriana em 11 (21,1% pacientes, sendo pulmonar (n=5, peritonite bacteriana espontânea (PBE (n=2, urinária (n=3 e dermatológica (n=1. Óbito precoce, durante o período de internação ocorreu em 8 (15,4% casos e a análise comparativa entre eles e os sobreviventes mostrou serem fatores de mau prognóstico a presença de encefalopatia hepática (p=0,012, bilirrubinas > 20mg% (p=0,012 e associação com infecções graves (pulmonar/PBE, com p=0,004. Em conclusão, demonstramos que as infecções bacterianas são fatores de mau prognóstico na hepatite alcoólica. Recomendamos, portanto, que a profilaxia com antibióticos que se faz durante hemorragia digestiva alta na cirrose e em casos de insuficiência hepática fulminante, seja estendida para a hepatite alcoólica, em sua forma grave, com finalidade de evitar infecções bacterianas e mortalidade precoce.Bacterial infections increase morbidity and mortality in cirrhosis. Our aim was to investigate whether in alcoholic hepatitis the development of bacterial infections was also a poor prognostic factor. In the retrospective evaluation of 681 hospitalized patients with liver disease

  9. Aislamiento y selección de una cepa bacteriana degradadora de hidrocarburos a partir de suelos contaminados con petróleo

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    Rosa María Pérez Silva

    2008-01-01

    Full Text Available El conocimiento científico acerca del papel que desempeñan los microorganismos en el tratamiento de agentes contaminantes del medio ambiente como el petróleo, es esencial para prevenir y controlar los daños que puedan ocasionar los derrames o fugas de estos contaminantes. La degradación de petróleo es un proceso que puede ocurrir de forma natural por los microorganismos nativos de las zonas contaminadas aprovechando sus rutas metabólicas. Por esta razón, en estos momentos se prevé que los microorganismos pueden ofrecer esta posibilidad en tecnologías basadas en el uso de estos en la remediación de la contaminación ambiental por petróleo y sus derivados. En el presente trabajo, se estudió la biodegradación de petróleo por cepas aisladas de suelos contaminados con petróleo, mediante un aislamiento realizado por enriquecimiento secuencial utilizando petróleo Mesa 30/Puerto escondido (80 : 20 como única fuente de carbono y energía. Se aislaron 9 cepas bacterianas, cinco Gram negativas y cuatro Gram positivas, que fueron identificadas según el Manual Bergey's, 1994. Las pruebas bioquímicas evaluadas confirmaron que las cepas aisladas AT14, AT15, AT16, AT17 y AT18 corresponden a Pseudomonas aeruginosa. En este estudio, se seleccionó la cepa Pseudomonas aeruginosa AT18, por mostrar mayor crecimiento sobre petróleo como única fuente de carbono y energía al obtenerse 1,83 g/L de biomasa celular, lo que representa un 57 % de biodegradación de petróleo.

  10. Validación de la prueba de Papanicolaou en el diagnóstico de vaginosis bacteriana. Antioquia, Colombia

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    María Elena Vásquez Peña

    2002-01-01

    Full Text Available A descriptive cross sectional study was carry out in 423 women in seven rural communities of the municipality of Amagá, Antioquia. One of the objectives of this study was to evaluate the sensibility and specificity and predictive values of the test of Papanicolaou in relation to the Gram exam, for the diagnosis of Bacterial Vaginosis (BV. In the 423 studied women the results showed a prevalence of BV for the bacteriological exam Gram of 20.8 % (88 cases and for Papanicolaou of 21% (89 cases. The sensitivity was 87.5%, the specificity was 96.4%. The value predictive positive was 86,5% and the value predictive negative was 96.7%. The high sensitivity, specificity and predictive values of the Papanicolaou test reported in this study make it a good screening method, since it is an exam that is carried out commonly and no additional testa are required. Se realizó un estudio descriptivo de corte en 423 mujeres de la población rural del municipio de Amagá, Antioquia, cuyas edades estaban comprendidas entre los 15 y 65 años, a quienes se les tomó muestras cérvicovaginales para estudio citológico de Papanicolau y coloración de Gram. El objetivo de este estudio fue evaluar la sensibilidad, especificidad y valores predictivos de la prueba de Papanicolaou frente al Gram, para el diagnóstico de vaginosis bacteriana (vb. La prevalencia de vb por el Gram, en las 423 mujeres estudiadas, fue de 20.8% (88 casos y la prevalencia de vb por Papanicolaou, fue del 21 % (89 casos. La sensibilidad fue 87.5%, la especificidad 96.4%, valor predictivo positivo (VPP 86,5% y valor predictivo negativo (VPN 96.7%. La alta sensibilidad, especificidad y valores predictivos de la prueba de Papanicolaou, reportados en este estudio hacen de ésta un buen método de tamizaje, dado que es un examen que se realiza de rutina y no se requiere una prueba adicional para hacer el diagnóstico; lo que a su vez permite disminuir costos porque se omite el estudio de la flora vaginal

  11. Pneumonia bacteriana em jabuti-piranga (Chelonoidis carbonaria: aspectos clínicos, microbiológicos, radiológicos e terapêutica

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    Marcelo M. Silveira

    2014-09-01

    Full Text Available A pneumonia é uma doença respiratória comum na clínica de répteis. Agentes infecciosos são capazes de causar pneumonia primária em répteis mantidos em cativeiro, porém na maioria dos casos, são secundárias a problemas de manejo, higiene e nutricionais. O objetivo desse trabalho foi relatar a ocorrência de pneumonia bacteriana em jabuti-piranga (Chelonoidis carbonaria, e descrever o diagnóstico clínico, microbiológico, radiográfico e a conduta terapêutica. O animal apresentava sinais de distúrbios respiratórios e foi descrito durante a anamnese que houve um diagnostico anterior de pneumonia. Os achados radiográficos foram sugestivos de pneumonia/edema pulmonar. Baseado nos exames radiográficos e sinais clínicos apresentados iniciou-se o tratamento com administração de Cloranfenicol (40mg/kg/SID/IM por 10 dias. Foram isoladas Klebsiella spp. e Citrobacter spp. da cultura bacteriana realizada da coleta de lavado endotraqueal. Ambas com perfil de resistência múltipla aos antibióticos testados. Instituiu-se protocolo terapêutico utilizando Gentamicina (5mg/kg/IM, em sete aplicações com intervalos de 72h. Após o segundo protocolo terapêutico notou-se melhora dos sinais clínicos do animal, porém foi observada a persistência de secreção nasal. Foi realizado novo exame radiográfico, demonstrando discreta diminuição na opacidade do campo pulmonar direito e nenhuma alteração significativa no campo pulmonar esquerdo na projeção craniocaudal. Devido à permanência do sinal clínico apresentado, nova coleta de material endotraqueal foi realizada, e houve isolamento de Citrobacter spp. e Enterobacter spp. A partir dos resultados obtidos no antibiograma, instituiu-se novo protocolo com uso de amicacina (2,5mg/kg/IM, em sete aplicações com intervalos de 72h. Após antibioticoterapia, outro exame radiológico foi realizado, e demonstrou redução satisfatória do quadro pulmonar, e sinais clínicos.

  12. Escova dental e dedeira na remoção da placa bacteriana dental em cães

    OpenAIRE

    Lima Tânia Berbert Ferreira; Eurides Duvaldo; Rezende Renata Junqueira; Milken Vanessa Martins Fayad; Silva Luiz Antonio Franco da; Fioravanti Maria Clorinda Soares

    2004-01-01

    A placa bacteriana é fator primário na formação de gengivite, cálculo dentário, halitose e doença periodontal. Objetivou-se avaliar a quantidade de placa bacteriana dental removida pela escova dental e dedeira. Foram utilizados 60 cães machos e fêmeas de diferentes raças, idade e peso, divididos em dois grupos. O índice Logan & Boyce foi utilizados para quantificar a placa bacteriana antes e após a escovação. Observou-se diferença estatística (p0,05) entre a utilização da escova dental e ...

  13. Caracterización de tres cepas bacterianas capaces de fijar nitrógeno y biodegradar hidrocarburos aisladas de un suelo de la Patagonia

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    A.J. Acuña

    2010-01-01

    Full Text Available El objetivo de este trabajo fue caracterizar tres microorganismos capaces de biodegradar hidrocarburos en ausencia de nitrógeno aislados a partir de un suelo de la Patagonia con una larga historia de contaminación por petróleo y sus derivados. Para ello se aislaron tres cepas bacterianas de un suelo patagónico con baja concentración de nitrógeno y contaminado con hidrocarburos. Estos fueron identificados por ARNr 16S y ácidos grasos de membrana. También se estudiaron sus perfiles de biodegradación de hidrocarburos en presencia y en ausencia de nitrógeno con hidrocarburos alifáticos, cíclicos, aromáticos y poliaromáticos. La capacidad de realizar fijación biológica de nitrógeno se estudió por reducción de acetileno y detección del gen nifD. Por otro lado, se realizó un estudio por desarrollo en cultivo líquido para conocer la adaptación a diferentes pH, entre 5 y 9, temperatura, de 15 a 65 °C, y concentraciones crecientes de NaCl entre 0 y 3M. Los microorganismos aislados correspondieron a los géneros Pseudomonas, Bacillus y Gordonia, todos con capacidad de fijar nitrógeno. Las cepas biodegradaron casi la totalidad de los hidrocarburos ensayados en presencia y ausencia de nitrógeno y tuvieron una buena adaptación a los cambios de pH, temperatura y concentración de NaCl, demostrando una buena adaptación a los principales factores de estrés en los suelos patagónicos.

  14. Resistencia bacteriana a los antibióticos: una crisis global

    OpenAIRE

    Alós Cortés, Juan Ignacio

    2015-01-01

    La introducción de los antibióticos en la práctica clínica supuso una de las intervenciones más importantes para el control de las enfermedades infecciosas. Los antibióticos han salvado millones de vidas, y además han supuesto una revolución en la medicina. Sin embargo, una amenaza creciente deteriora la eficacia de estos fármacos: la resistencia bacteriana a los antibióticos, que se define en este trabajo como la capacidad de una bacteria para sobrevivir en concentraciones de antibiótico que...

  15. Microbiota bacteriana asociada a los cultivos de dos especies de diatomeas bentónicas.

    OpenAIRE

    Hernández-Zulueta, Joicye; Leal, Sylvia; Loza, Sandra

    2014-01-01

    Las diatomeas bentónicas forman biopelículas debido a las sustancias que secretan, que les permite mantenerse adheridas al sustrato. A ellas se asocian bacterias que, dada las condiciones no axénicas de los cultivos, pueden alterar su valor nutricional. El objetivo del presente trabajo fue caracterizar la microbiota bacteriana asociada a los cultivos de las microalgas bentónicas Navicula germanopolonica y Amphora sp., especies utilizadas para la precría del camarón en cultivo. Se aislaron e i...

  16. Caracterização da microbiota bacteriana de Biomphalaria glabrata (Say, 1818)(Mollusca: Gastropoda)

    OpenAIRE

    Silva, Tatiana Maria da

    2012-01-01

    Devido a grande importância da microbiota no desenvolvimento de parasitas nos invertebrados, muitos estudos vêm sendo desenvolvidos para o melhor entendimento desta interação. Desta forma, a associação entre microrganismos e seus hospedeiros invertebrados, vetores de doenças, está se tornando cada vez mais evidente. Com base nisto, o objetivo do presente estudo foi caracterizar a microbiota bacteriana de caramujos da espécie Biomphalaria glabrata, principal hospedeiro interm...

  17. Desarrollo de Nanocompuestos de Celulosa Bacteriana para Aplicaciones Biomédicas

    OpenAIRE

    Grande Cruz, Cristian Jaime

    2014-01-01

    La celulosa bacteriana es un polisacárido obtenido a partir de microorganismos de la especie Gluconacetobacter cuando son cultivados en medios que contienen fuentes de carbono y nitrógeno. El material que se obtiene a partir de los procesos bioquímicos que ocurren dentro de la membrana celular de las bacterias se presenta físicamente como un gel que contiene agua y fibras de celulosa de alta pureza, cuyas dimensiones de sección se encuentran en el orden de los nanómetros. Debido a sus buenas ...

  18. Los bacteriófagos como una alternativa en el tratamiento de enfermedades infecciosas Bacterianas (Fagoterapia)

    OpenAIRE

    Nallelyt Segundo A.; Efrén Hernández B.; Oliver López V.; Oscar Torres A.

    2010-01-01

    Los bacteriófagos son virus que infectan y lisan bacterias. Se han aplicado en: Biología Molecular e Investigación Clínica, principalmente en el tratamiento de infecciones bacterianas (Fagoterapia). Los bacteriófagos se han utilizado contra Pseudomonas, Staphylococcus, Escherichia y Mycobacterium, resistentes a antibióticos. Existen compañías que comercializan fagos para terapia en humanos o animales además de otras aplicaciones como sanitizantes. Sin embargo, las farmacopeas mexicana y estad...

  19. Nanocompósitos baseados em celulose bacteriana para aplicações ópticas

    OpenAIRE

    Santos, Molíria Vieira dos [UNESP

    2012-01-01

    Neste trabalho membranas de biocelulose ou celulose bacteriana (CB), obtidas de meios de cultura da bactéria Gluconacetobacter xylinus, foram utilizadas como matriz para preparação de novos compósitos, a saber, celulose - colóides metálicos, celulose - sílica e celuloses - composto de európio. Nanopartículas (NP) esféricas de prata, ouro e prata-ouro, foram preparadas utilizando-se citrato de sódio e/ou pectina como agentes ao mesmo tempo redutores e estabilizantes. As propriedades ópticas de...

  20. Epidemiology of bacterial meningitis among children in Brazil, 1997-1998 Epidemiologia de meningites bacterianas entre crianças no Brasil, 1997 a 1998

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    Débora PL Weiss

    2001-06-01

    , atendimento em pronto-socorros, certificados de óbito, autópsias ou atendimentos em ambulatórios. RESULTADOS: A incidência de meningites bacterianas (n=274 foi de 334,9; 115 e 43,5 casos por 10(5 pessoas-ano entre residentes, em Campinas, com idade inferior a 1,5 e 20 anos, respectivamente. Em todos os casos houve hospitalização com uma média de permanência no hospital de 12 dias. O uso prévio de antimicrobianos notificado foi de 4,0%. A taxa de mortalidade total devida a meningites bacterianas entre pessoas com idade inferior a 20 anos foi de 9% (24/274, com 75% das mortes ocorrendo entre crianças com idade inferior a 5 anos. A incidência de meningites causadas por Haemophilus influenzae tipo b (Hib (n=26 foi de 62,8 e 17 casos por 10(5 pessoas-ano em crianças com idade inferior a 1 e 5 anos, respectivamente. CONCLUSÕES: A incidência e a epidemiologia descritiva de meningites causadas por Haemophilus influenzae tipo b (Hib, entre crianças com idade inferior a 5 anos, em Campinas, SP, Brasil, durante o período de 1997 a 1998, foram semelhantes às relatadas pelos Estados Unidos, Europa Ocidental e Israel no período anterior ao extenso uso da vacina contra o Haemophilus influenzae tipo b nessas regiões. O estudo fornece valores de referência para outras pesquisas posteriores que avaliem mudanças na etiologia e na incidência de meningites bacterianas em crianças, depois da introdução de vacinação rotineira contra Haemophilus influenzae tipo b, no Brasil.

  1. Fontes de resistência à murcha bacteriana em germoplasma de Capsicum spp. do estado do Amazonas Sources of resistance against bacterial wilt in Capsicum spp. germoplasm of the Amazonas state

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    Liane Cristine Rebouças Demosthenes

    2011-01-01

    Full Text Available A murcha bacteriana, causada por Ralstonia solanacearum, é uma das doenças mais importantes do gênero Capsicum no Brasil. No Amazonas, as condições de elevada temperatura e umidade favorecem o desenvolvimento da doença. O objetivo deste trabalho foi avaliar a resistência à murcha bacteriana de germoplasma, selvagem e comercial, de Capsicum spp. Foram avaliados 22 acessos de Capsicum em casa de vegetação. A inoculação foi feita mediante ferimento das raízes, seguido de adição no solo, ao redor das plantas, de suspensão bacteriana na concentração de 10(8 ufc mL-1. A avaliação foi feita diariamente a partir do quarto dia após a inoculação, em função desenvolvimento dos sintomas. A partir das médias de progresso dos sintomas foi construída a área abaixo da curva de progresso da doença (AACPD, e os dados submetidos ao teste de Scott-Knott ao nível de 5% de probabilidade, utilizando o programa estatístico SAEG 9.1. Foram selecionados os acessos 30, 20 e 17, da espécie C. chinense, como resistentes à murcha bacteriana para ensaios futuros em programas de melhoramento genético.The bacterial wilt caused by Ralstonia solanacearum is one of the most important in the genus Capsicum in Brazil. In the state of Amazonas, high temperatures and humidity favor the development of the disease. The objective of this work was to evaluate resistance in germoplasm of wild and commercial Capsicum spp. to bacterial wilt. Twenty two accesses of Capsicum spp. were evaluated in greenhouse conditions. The inoculation was made by means of wounds in the roots, followed by addition of bacterial suspension in the concentration of 10(8 ufc ml-1 in the soil, around the plants. Plant evaluation was made daily after the fourth day of the inoculation (DAI considering the symptoms progress. From the average progress of symptoms was constructed the area under the disease progress curve (AUDPC, and the data submitted to the Scott-Knott test at 5% of

  2. Acute bacterial meningitis in HIV, pacients in southern Brazil: Curitiba, Paraná, Brazil Meningite bacteriana aguda em portadores de HIV, no sul do Brasil: Curitiba, Paraná, Brasil

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    Sérgio M. de Almeida

    2007-06-01

    Full Text Available Acute communitarian bacterial meningitis and AIDS are prevalent infectious disease in Brazil. The objective of this study was to evaluate the frequency of acute communitarian bacterial meningitis in AIDS patients, the clinical and cerebrospinal fluid (CSF characteristics. It was reviewed the Health Department data from city of Curitiba, Southern Brazil, from 1996 to 2002. During this period, 32 patients with AIDS fulfilled criteria for acute bacterial meningitis, representing 0.84% of the AIDS cases and 1.85% of the cases of bacterial meningitis. S. pneumoniae was the most frequent bacteria isolated. The number of white blood cells and the percentage of neutrophils were higher and CSF glucose was lower in the group with no HIV co-infection (p 0.12; 0.008; 0.04 respectively. Bacteria not so common causing meningitis can occur among HIV infected patients. The high mortality rate among pneumococcus meningitis patients makes pneumococcus vaccination important.A meningite bacteriana aguda comunitária e a AIDS são doenças prevalentes no Brasil. O objetivo desse estudo foi avaliar a freqüência de meningite bacteriana aguda comunitária entre os pacientes com AIDS e as características clínicas e do líquido cefalorraquidiano (LCR. Foram revistos os dados da Secretaria Municipal da Saúde, Curitiba, Paraná, Brasil, nos anos de 1996 a 2002. Nesse período, 32 pacientes com AIDS preencheram os critérios para meningite bacteriana aguda, representando 0,84% dos casos com AIDS e 1,85% dos casos com meningite bacteriana aguda. A bactéria mais freqüentemente isolada foi S. pneumoniae. A celularidade total e a porcentagem de neutrófilos no LCR foi mais elevada e a glicose foi mais baixa no grupo sem co-infecção (p 0,12; 0,008; 0,04 respectivamente. Bactérias menos freqüentes como agentes etiológicos de meningite podem ocorrer. A taxa de mortalidade elevada entre pacientes com meningite por pneumococo torna a vacinação importante.

  3. Revisão sistemática do uso da dexametasona como terapia adjuvante na meningite bacteriana em crianças Revisión sistemática del uso de la dexametasona como terapia adyuvante en la meningitis bacteriana en niños Systematic review of dexamethasone as an adjuvant therapy for bacterial meningitis in children

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    João Antonio G. G. Prats

    2012-12-01

    Full Text Available OBJETIVO: Analisar a melhor evidência disponível nos últimos 15 anos com relação aos benefícios da terapia adjuvante com dexametasona na meningite bacteriana em população pediátrica. FONTES DE DADOS: Das bases de dados Medline, Lilacs e SciELO, foram analisados ensaios clínicos randomizados de 1996 a 2011, os quais comparavam a dexametasona ao placebo e/ou a outra terapia adjuvante em pacientes com meningite bacteriana diagnosticada laboratorialmente por critérios quimiocitológicos e/ou bacteriológicos, na faixa etária de 29 dias aos 18 anos. Os desfechos avaliados foram mortalidade e ocorrência de sequelas neurológicas e/ou auditivas. Foram excluídos estudos relacionados à meningite tuberculosa. SÍNTESE DOS DADOS: Com os critérios utilizados, foram identificadas cinco publicações correspondentes a quatro protocolos de estudo. Nenhum dos estudos mostrou diferenças entre a dexametasona e o placebo para os desfechos avaliados. Os estudos analisados tiveram alta qualidade (escore de Jadad et al=5. CONCLUSÕES: As evidências encontradas na literatura são insuficientes para indicar de forma rotineira o uso da dexametasona como terapia adjuvante para redução de mortalidade, perda auditiva e sequelas neurológicas em pacientes pediátricos com meningite bacteriana não tuberculosa.OBJETIVO: El presente estudio tiene por objetivo el análisis de la mejor evidencia disponible los últimos 15 años respecto a los beneficios de la terapia adyuvante con dexametasona en la meningitis bacteriana en población pediátrica por medio de revisión sistemática. FUENTES DE DATOS: De las bases de datos Medline, Lilacs y ScieLO, se analizaron ensayos clínicos aleatorios de 1996 a 2011 que comparaban la dexametasona al placebo y/u otra terapia adyuvante, en pacientes con meningitis bacteriana diagnosticada laboratorialmente por criterios quimiocitológicos y/o bacteriológicos, en la franja de edad de 29 días a 18 años. Los desenlaces

  4. Evaluation of tomato rootstocks and its use to control bacterial wilt diseaseAvaliação de porta-enxertos de tomateiro e o uso da enxertia no controle da murcha bacteriana

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    Francisco Ferraz Laranjeira

    2012-05-01

    ção da resistência a R. solanacearum, utilizaram-se quatro genótipos de tomateiro silvestres coletados em diferentes regiões da Bahia, a cv. Santa Clara como testemunha suscetível e o Hawaii 7996 (H7996 como testemunha resistente. Para a avaliação da enxertia no controle da murcha bacteriana do tomateiro, utilizou-se como porta-enxerto o H7996 e como enxerto as cultivares Santa Clara, Santa Cruz Kada e Débora Plus. Os dois experimentos foram avaliados em infectário de R. solanacearum, por um período de 65 dias, para a seleção de porta-enxertos e 45 dias para a avaliação da enxertia, observando-se o sintoma de murcha bacteriana. Apenas o H7996 pode ser recomendado como porta-enxerto resistente a R. solanacearum. Os demais genótipos apresentaram suscetibilidade ao patógeno. A enxertia com esse híbrido não apresentou incompatibilidade com as cultivares avaliadas e promoveu 100 % de controle da murcha bacteriana, em todos os tratamentos, sugerindo que essa técnica pode ser utilizada como método alternativo de controle da murcha bacteriana, permitindo a produção de cultivares comerciais de tomateiro, suscetíveis à doença, em áreas infestadas com R. solanacearum.

  5. Administração endovenosa de antibióticos e resistência bacteriana: responsabilidade da enfermagem

    OpenAIRE

    Heloisa Helena Karnas Hoefel; Liana Lautert

    2006-01-01

    O sucesso da terapêutica com antibióticos e o desenvolvimento da resistência bacteriana dependem de diversos fatores, sendo que os relacionados ao cuidado de enfermagem são o seu preparo e a sua administração. Objetivo: realizar uma revisão da literatura sobre falhas na administração de antibióticos analisando sua possível influência na resistência bacteriana. Delineamento: realizada uma pesquisa bibliográfica das fontes do LILACS e Medline. Métodos: realizada revisão bibliográfica sistematiz...

  6. Administração endovenosa de antibióticos e resistência bacteriana : responsabilidade da enfermagem

    OpenAIRE

    Hoefel, Heloisa Helena Karnas; Lautert, Liana

    2006-01-01

    O sucesso da terapêutica com antibióticos e o desenvolvimento da resistência bacteriana dependem de diversos fatores, sendo que os relacionados ao cuidado de enfermagem são o seu preparo e a sua administração. Objetivo: realizar uma revisão da literatura sobre falhas na administração de antibióticos analisando sua possível influência na resistência bacteriana. Delineamento: realizada uma pesquisa bibliográfica das fontes do LILACS e Medline. Métodos: realizada revisão bibliográfica sistematiz...

  7. Perfil etiológico das meningites bacterianas em crianças Etiological profile of bacterial meningitis in children

    OpenAIRE

    Mantese,Orlando C.; Jorge Hirano; Silva,Valéria M.; Irenize C. Santos; Elísio de Castro

    2002-01-01

    Objetivo: analisar o perfil etiológico e alguns aspectos epidemiológicos das crianças com meningite bacteriana, internadas em um hospital público universitário. Métodos: foram seguidas, prospectivamente, as crianças internadas com meningite bacteriana, diagnosticada segundo os critérios clínicos e laboratoriais habituais. Foram excluídos os casos de meningite pós-trauma, de meningite na vigência de derivação liquórica, ou de defeitos congênitos do tubo neural, e de meningite tuberculosa. Resu...

  8. Evolução do comportamento auditivo após meningite bacteriana: relato de caso Auditory behaviour monitoring after bacterial meningitis: case report

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    Ida Lichtig

    1997-06-01

    Full Text Available A deficiência auditiva adquirida tem nas meningites bacterianas a sua principal etiologia e pouco tem-se dito a respeito da evolução para melhora ou piora do comportamento auditivo após a alta hospitalar. O presente estudo descreve o caso de um menino que teve meningite por Haemophilus influenzae aos 5 meses de vida e que entre outras complicações apresentou diminuição da acuidade auditiva detectada na evolução imediata, com melhora significativa posteriormente, confirmada por testes qualitativos e quantitativos. Discute-se a importância e a necessidade do seguimento fonoaudiológico de tais indivíduos para estabelecer orientação adequada.Bacterial meningitis is the main cause for acquired hearing loss. Nevertheless very little has been written about the development of the auditory behaviour either for improvement or for deterioration, after hospital release. The present study describes the case of a five month old boy with Haemophilus influenzae meningitis. Amongst various complications, a decrement in the auditory acuity was detected in the immediate evolution, with significant improvement later on by qualitative and quantitative tests.

  9. Clinical Practice Guidelines for Bacterial Meningoencephalitis. Guía de práctica clínica para el tratamiento de la meningoencefalitis bacteriana.

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    Luciano Núñez Almoguea

    2009-03-01

    Full Text Available Clinical Practice Guidelines for Bacterial Meningoencephalitis. It has been defined as an acute inflammatory process caused by bacteria, often purulent, which involves the meninges, subarachnoid space around the brain, spinal cord and usually includes the ventricles. It is caused in the 80% of the patients by three bacteria: Haemophilus influenzae, Neisseria meningitides and Streptococcus pneumonia. Concepts, classification, diagnosis and treatment were reviewed. It includes assessment guidelines focused on the most important aspects to be accomplished.Guía de práctica clínica para el tratamiento de la meningoencefalitis bacteriana. Definida como un proceso inflamatorio agudo causado por bacterias, muchas veces purulento, que involucra a membranas meníngeas, espacio subaracnoideo alrededor del cerebro, médula espinal y suele incluir los ventrículos. Causada en cerca del 80 % por tres bacterias: Haemophilus influenzae, Neisseria meningitidis y Streptococcus pneumoniae. Se revisan los conceptos, clasificación, diagnóstico y tratamiento. Concluye con su guía de evaluación, enfocada en los aspectos más importantes a cumplir.

  10. Role of intestinal bacterial overgrowth and intestinal motility in bacterial translocation in experimental cirrhosis Papel del sobrecrecimiento bacteriano intestinal y de la motilidad intestinal en la traslocación bacteriana en un modelo experimental de cirrosis

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    E. Sánchez

    2005-11-01

    Full Text Available Background: intestinal bacterial overgrowth (IBO is related to small bowel motility and has been involved in the pathogenesis of bacterial translocation (BT in experimental models, and both overgrowing gut flora and translocating bacteria to mesenteric lymph nodes are common features in cirrhosis. Objectives: the aims of this study were to analyze cecal aerobic bacteria and intestinal transit in cirrhotic rats, and their relationship with BT, evaluating the role of intestinal bacterial overgrowth and small bowel dismotility in the development of BT in experimental cirrhosis. Material and methods: we included twenty-seven male Sprague-Dawley rats with carbon tetrachloride-induced cirrhosis without ascites and ten controls. Cultures of mesenteric lymph nodes (MLN, peripheral and portal blood, liver, spleen and cecal samples were carried out. Small intestinal transit was determined in ten cirrhotic rats and in ten control rats. Results: the prevalence of bacterial translocation was 56%. Total cecal aerobic bacteria count was significantly higher in cirrhotic rats than in control rats (p Introducción: el sobrecrecimiento bacteriano intestinal (SBI está relacionado con la motilidad del intestino delgado y diferentes trabajos con modelos experimentales han sugerido su relación con el desarrollo de traslocación bacteriana (TB. Tanto el sobrecrecimiento bacteriano intestinal como la traslocación bacteriana son eventos frecuentes en la cirrosis hepática. Objetivos: los objetivos de este estudio han sido analizar la población cecal de bacterias aerobias y el tránsito intestinal en un modelo de ratas cirróticas y su relación con la TB. Material y métodos: el estudio se ha realizado en un modelo experimental de cirrosis inducida por tetracloruro de carbono por vía oral en ratas Sprague-Dawley. Se llevaron a cabo cultivos microbiológicos convencionales a partir de ganglios linfáticos mesentéricos (GLM, sangre portal y periférica, h

  11. Endocardite bacteriana em paciente com diabetes mellitus tipo 2

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    Alcinda Aranha Nigri

    2016-10-01

    Full Text Available Introdução: A endocardite infecciosa é uma infecção microbiana da superfície do endocárdio. Acomete sobretudo valvas cardíacas, em geral, a mitral. Etiologias comuns são: uso de drogas injetáveis, infecção oral, hemodiálise a longo prazo e diabetes mellitus (DM. O diagnóstico é realizado por meio dos Critérios de Duke. Objetivos: Relatar caso de endocardite de paciente do Hospital Santa Lucinda (HSL. Metodologia: As informações foram obtidas pelo exame clínico, prontuário da paciente, relato da equipe médica e revisão de literatura. Relato de Caso: Paciente L.F.P.L., F., 54 anos, DM tipo 2, hipertensa, com insuficiência renal crônica não-dialítica, com úlceras de membros inferiores (MMII. Foi realizado debridamento e uso de antibiótico (ATB. Posteriormente, procurou hospital com queixa de dispneia. Diagnosticada com pneumonia (sic, usou ATB. A posteriori, apresentou anasarca e febre. Não houve leucocitose provavelmente devido ao uso de ATB. Constatou-se sopro mitral; no ecocardiograma: insuficiência mitral e tricúspide e vegetação em valva mitral, indicando endocardite infecciosa. Encaminhada ao HSL para cirurgia, apresentou na admissão: derrame pleural, hemo- e leucograma (LEU sem alterações, ureia 142, glicose 256 (mg/dL e albumina 2,6 (g/dL. Após 6 dias, foi inserida a prótese biomitral e cerclagem de valva tricúspide. Realizou-se transfusões sanguíneas pós-cirúrgicas. Manifestou parada cardiorrespiratória (PCR, realizada ressuscitação cardiopulmonar. Após 10 dias, apresentou arritmia, PCR, sepse e foi a óbito. Conclusões: O manejo adequado do DM pode evitar complicações, como úlceras de MMII, evitando, consequentemente, a disseminação via hematogênica e o quadro de endocardite. Deve-se considerar o uso prévio de ATB ao se analisar o LEU do paciente.

  12. EXPRESSION OF A CHITINASE GENE FROM SERRATIA-MARCESCENS IN LACTOCOCCUS-LACTIS AND LACTOBACILLUS-PLANTARUM

    NARCIS (Netherlands)

    BRURBERG, MB; HAANDRIKMAN, AJ; LEENHOUTS, KJ; VENEMA, G; NES, IF

    1994-01-01

    A chitinase gene from the Gram-negative bacterium Serratia marcescens BJL200 was cloned in Lactococcus lactis subsp. lactis MG1363 and in the silage inoculum strain Lactobacillus plantarum E19b. The chitinase gene was expressed as an active enzyme at a low level in Lactococcus lactis, when cloned in

  13. Enhancement of Nisin Production by Lactococcus lactis subsp. lactis.

    Science.gov (United States)

    Dussault, Dominic; Vu, Khanh Dang; Lacroix, Monique

    2016-09-01

    Lactococcus lactis subsp lactis BSA (L. lactis BSA) was isolated from a commercial fermented product (BSA Food Ingredients, Montreal, Canada) containing mixed bacteria that are used as starter for food fermentation. In order to increase the bacteriocin production by L. lactis BSA, different fermentation conditions were conducted. They included different volumetric combinations of two culture media (the Man, Rogosa and Sharpe (MRS) broth and skim milk), agitation level (0 and 100 rpm) and concentration of commercial nisin (0, 0.15, and 0.30 µg/ml) added into culture media as stimulant agent for nisin production. During fermentation, samples were collected and used for antibacterial evaluation against Lactobacillus sakei using agar diffusion assay. Results showed that medium containing 50 % MRS broth and 50 % skim milk gave better antibacterial activity as compared to other medium formulations. Agitation (100 rpm) did not improve nisin production by L. lactis BSA. Adding 0.15 µg/ml of nisin into the medium-containing 50 % MRS broth and 50 % skim milk caused the highest nisin activity of 18,820 AU/ml as compared to other medium formulations. This activity was 4 and ~3 times higher than medium containing 100 % MRS broth without added nisin (~4700 AU/ml) and 100 % MRS broth with 0.15 µg/ml of added nisin (~6650 AU/ml), respectively.

  14. Therapeutic drug delivery by genetically modified Lactococcus lactis.

    Science.gov (United States)

    Steidler, Lothar; Rottiers, Pieter

    2006-08-01

    Food-grade bacteria have been consumed throughout history without associated pathologies and are, therefore, absolutely safe to ingest. Unexpectedly, Lactococcus lactis (L. lactis), known from cheese production, can be genetically engineered to constantly secrete satisfactory amounts of bioactive cytokines. Both of these features enabled the development of a new kind of topical delivery system: topical and active delivery of therapeutic proteins by genetically modified micro-organisms. The host organism's record inspired the development of applications that target intestinal diseases. In a variety of mouse models, chronic colon inflammation can be successfully treated with (interleukin) IL-10-secreting L. lactis. Trefoil factor (TFF) producer strains have also been shown to be very effective in the treatment of acute colitis. Such novel therapeutic strains are textbook examples of genetically modified (GM) organisms. There are legitimate concerns with regard to the deliberate release of GM micro-organisms. On development of these applications, therefore, we have engineered these bacteria in such a way that biological containment is guaranteed. The essential gene thyA, encoding thymidylate synthase, has been exchanged for IL-10. This makes the GM strain critically dependent on thymidine. Lack of thymidine, for example, resulting from thymidine consumption by thyA-deficient strains-will irreversibly lead to induced "thymidine-less death." This accomplishment has created the possibility of using this strategy for application in human medicine.

  15. Evolution of Lactococcus lactis phages within a cheese factory.

    Science.gov (United States)

    Rousseau, Geneviève M; Moineau, Sylvain

    2009-08-01

    We have sequenced the double-stranded DNA genomes of six lactococcal phages (SL4, CB13, CB14, CB19, CB20, and GR7) from the 936 group that were isolated over a 9-year period from whey samples obtained from a Canadian cheese factory. These six phages infected the same two industrial Lactococcus lactis strains out of 30 tested. The CB14 and GR7 genomes were found to be 100% identical even though they were isolated 14 months apart, indicating that a phage can survive in a cheese plant for more than a year. The other four genomes were related but notably different. The length of the genomes varied from 28,144 to 32,182 bp, and they coded for 51 to 55 open reading frames. All five genomes possessed a 3' overhang cos site that was 11 nucleotides long. Several structural proteins were also identified by nano-high-performance liquid chromatography-tandem mass spectrometry, confirming bioinformatic analyses. Comparative analyses suggested that the most recently isolated phages (CB19 and CB20) were derived, in part, from older phage isolates (CB13 and CB14/GR7). The organization of the five distinct genomes was similar to the previously sequenced lactococcal phage genomes of the 936 group, and from these sequences, a core genome was determined for lactococcal phages of the 936 group.

  16. A review on Lactococcus lactis: from food to factory.

    Science.gov (United States)

    Song, Adelene Ai-Lian; In, Lionel L A; Lim, Swee Hua Erin; Rahim, Raha Abdul

    2017-04-04

    Lactococcus lactis has progressed a long way since its discovery and initial use in dairy product fermentation, to its present biotechnological applications in genetic engineering for the production of various recombinant proteins and metabolites that transcends the heterologous species barrier. Key desirable features of this gram-positive lactic acid non-colonizing gut bacteria include its generally recognized as safe (GRAS) status, probiotic properties, the absence of inclusion bodies and endotoxins, surface display and extracellular secretion technology, and a diverse selection of cloning and inducible expression vectors. This have made L. lactis a desirable and promising host on par with other well established model bacterial or yeast systems such as Escherichia coli, Salmonella cerevisiae and Bacillus subtilis. In this article, we review recent technological advancements, challenges, future prospects and current diversified examples on the use of L. lactis as a microbial cell factory. Additionally, we will also highlight latest medical-based applications involving whole-cell L. lactis as a live delivery vector for the administration of therapeutics against both communicable and non-communicable diseases.

  17. Recombinant expression of Laceyella sacchari thermitase in Lactococcus lactis.

    Science.gov (United States)

    Jørgensen, Casper M; Madsen, Søren M; Vrang, Astrid; Hansen, Ole C; Johnsen, Mads G

    2013-12-01

    Thermitase (EC 3.4.21.66) is a thermostable endo-protease with the ability to convert various food relevant substrates into low-molecular weight peptides. A thermitase produced by Laceyella sacchari strain DSM43353 was found to have a mature amino acid sequence nearly identical to that of the original thermitase isolated from Thermoactinomyces vulgaris. The DSM43353 thermitase gene sequence contains a pro-peptide including parts of an I9 inhibitor motif. Expression of the thermitase gene in the Lactococcus lactis P170 expression system allowed secretion of stable thermitase in an auto-induced fermentation setup at 30°C. Thermitase accumulated in the culture supernatant during batch fermentations and was easily activated at 50°C or by prolonged dialysis. The activation step resulted in an almost complete degradation of endogenous L. lactis host proteins present in the supernatant. Mature activated product was stable at 50°C and functional at pH values between pH 6 and pH 11, suggesting that substrate hydrolysis can be performed over a broad range of pH values. The L. lactis based P170 expression system is a simple and safe system for obtaining food compatible thermitase in the range of 100 mg/L.

  18. Expression of biologically active murine interleukin-18 in Lactococcus lactis.

    Science.gov (United States)

    Feizollahzadeh, Sadegh; Khanahmad, Hossein; Rahimmanesh, Ilnaz; Ganjalikhani-Hakemi, Mazdak; Andalib, Alireza; Sanei, Mohammad Hossein; Rezaei, Abbas

    2016-11-01

    The food-grade bacterium Lactococcus lactis is increasingly used for heterologous protein expression in therapeutic and industrial applications. The ability of L. lactis to secrete biologically active cytokines may be used for the generation of therapeutic cytokines. Interleukin (IL)-18 enhances the immune response, especially on mucosal surfaces, emphasizing its therapeutic potential. However, it is produced as an inactive precursor and has to be enzymatically cleaved for maturation. We genetically manipulated L. lactis to secrete murine IL-18. The mature murine IL-18 gene was inserted downstream of a nisin promoter in pNZ8149 plasmid and the construct was used to transform L. lactis NZ3900. The transformants were selected on Elliker agar and confirmed by restriction enzyme digestion and sequencing. The expression and secretion of IL-18 protein was verified by SDS-PAGE, western blotting and ELISA. The biological activity of recombinant IL-18 was determined by its ability to induce interferon (IFN)-γ production in L. lactis co-cultured with murine splenic T cells. The amounts of IL-18 in bacterial lysates and supernatants were 3-4 μg mL(-1) and 0.6-0.7 ng mL(-1), respectively. The successfully generated L. lactis strain that expressed biologically active murine IL-18 can be used to evaluate the possible therapeutic effects of IL-18 on mucosal surfaces.

  19. Efecto de la adición de materia orgánica sobre la dinámica poblacional bacteriana del suelo en cultivos de papa y maíz

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    David García Ventocilla

    2012-02-01

    Full Text Available Se determinó el efecto de la fertilización orgánica sobre las poblaciones bacterianas del suelo en cultivos de papa y maíz durante la campaña agrícola 2008-2009 en terrenos de cuatro localidades del Valle del Mantaro: INIA Santa Ana (Huancayo, en la EEA El Mantaro (Jauja, Vista Alegre y Huayao (ambos en Chupaca. En estos lugares se instalaron parcelas experimentales de papa (Solanum tuberosum L. Var. Canchan y maíz (Zea maíz L. Var. Cusco mejorado bajo abonamiento orgánico (vacuno, ovino, cuy, fertilización química y sin fertilización alguna (testigo. Para dicho efecto se empleó las técnicas de la Electroforesis en Gel de Gradiente Desnaturalizante (DGGE con amplificación de la región 968 – 1401 del rDNA 16S. Los resultados obtenidos muestran que la variabilidad de las poblaciones bacterianas en los suelos está afectado directamente por el tipo de cultivo mas no por el tipo de fertilización ya que el efecto de este último resulta variable para cada zona experimental y cultivo encontrándose solo en la zona experimental de Chupaca - Maíz una segregación de los tratamientos con fertilización orgánica de los tratamientos químicos. También se ha encontrado que la variación de las comunidades microbianas no sufre variaciones significativas en los suelos con cultivos de maíz obteniéndose coeficientes de similaridad para todos los tratamientos por encima del 80% mientras que para los tratamientos en los cultivos de papa dicho coeficiente fue de tan solo del 60%.

  20. Evolution of Lactococcus strains during ripening in Brie cheese using Fourier transform infrared spectroscopy

    OpenAIRE

    Lefier, Dominique; Lamprell, Helen; Mazerolles, Gérard

    2000-01-01

    International audience; The diversity of the Lactococcus flora during maturation of soft cheese, produced using one of 2 different starter cultures (S$_{\\rm A}$ and S$_{\\rm B}$), was determined using Fourier transform infrared spectroscopy (FTIR). Identification of Lactococcus sp. was achieved using a model composed of the 6 strains of Lc. lactis ssp. lactis and the 2 strains of Lc. lactis ssp. cremoris, present in the starter cultures S$_{\\rm A}$ and S$_{\\rm B}$, as well as a reference strai...

  1. Placa bacteriana dentária em cães Dental bacterial plaque in dogs

    Directory of Open Access Journals (Sweden)

    Duvaldo Eurides

    1996-12-01

    Full Text Available Com objetivo de avaliar a incidência de placa bacteriana dentária, foram utilizados 30 cães, sem raça definida, distribuídos em três grupos iguais, de acordo com a faixa etária, sendo o grupo I de 0 a 2 anos, o grupo II de 3 a 5 anos e o grupo III acima de 6 anos. Os animais foram submetidos a anestesia geral e sobre os dentes foi aplicado cloreto de metilrosanilina, para evidenciar acúmulos bacterianos. As placas encontravam-se distribuídas em 80,99% no grupo I, 71,45% no grupo II e 83,96% no grupo III. Os grupos dentários foram considerados separadamente, apresentando índices de 64,84% nos dentes incisivos, 84,80% nos caninos, 87,23% nos pré-molares e 78,34% nos molares. Nos três grupos de cães observou-se índices semelhantes de placa bacteriana nos diferentes grupos dentários. Os animais do grupo II e o grupo de dentes incisivos apresentaram menores índices de placa bacteriana.To avaliate the incidence of bacterial plaque 30 mogreal dogs were utilizated, distributed among three equal groups. According to age, group I was composed of 0 to 2 years-old dogs, group II was 3 to 5 years-old, and group III over 6 years-old. The animals underwent a general anesthesia and metilrosanilin cloret was applied over the tooth, to evidence the bacterial mass. The plaques were distributed to 80.99% in group I, 71.42% in group II and 83.96% in group III. The dental groups were considerated apart, showing index of 64.84% on the incisar tooth, 84.80% on the canine tooth, 87.23% on the premolar tooth, and 78.34% on the molar tooth. At the dogs groups, similar Índex of bacterial plaque were observed on the diffèrent dental groups. The dogs from group II and the incisive tooth group showed minar bacterial plaque index.

  2. Resistance to antibiotics in Lacid acid bacteria - strain Lactococcus

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    Filipić Brankica

    2015-01-01

    Full Text Available Lactic acid bacteria (LAB are widely used in the food industry, especially in the production of fermented dairy products and meat. The most studied species among Lis Lactococcus lactis. L. lactis strains are of great importance in the production of fermented dairy products such as yogurt, butter, fresh cheese and some kind of semi-hard cheese. Although L. lactis acquired the „Generally Regarded As Safe“ (GRAS status, many investigations indicated that lactococci may act as reservoirs of antibiotic resistance genes, which could be transferred to other bacterial species in human gastrointestinal tract includ­ing pathogens. The genome analysis of L. lactis indicated the presence of at least 40 putative drug transporter genes, and only four multidrug resistance (MDR transporters are functionally characterized: LmrA, LmrP, LmrCD i CmbT. LmrA is the first described MDR transporter in prokaryotes. LmrCD is responsible for resistance to cholate, which is an integral part of human bile and LmrCD is important for intestinal survival of lactococci that are used as probiotics. Secondary multidrug transporter LmrP confers resistance to lincosamides, macrolides, streptogramins and tetracyclines. CmbT protein has an effect on the host cell resistance to lincomycin, sulfadiazine, streptomycin, rifampicin, puromycin and sulfametox­azole. Since the food chain is an important way of transmitting resistance genes in human and animal population, it is of great importance to study the mechanisms of resistance in lactococci and other LAB, intended for the food industry. [Projekat Ministarstva nauke Republike Srbije, br. 173019: Izučavanje gena i molekularnih mehanizama u osnovi probiotičke aktivnosti bakterija mlečne kiseline izolovanih sa područja Zapadnog Balkana

  3. Genes but not genomes reveal bacterial domestication of Lactococcus lactis.

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    Delphine Passerini

    Full Text Available BACKGROUND: The population structure and diversity of Lactococcus lactis subsp. lactis, a major industrial bacterium involved in milk fermentation, was determined at both gene and genome level. Seventy-six lactococcal isolates of various origins were studied by different genotyping methods and thirty-six strains displaying unique macrorestriction fingerprints were analyzed by a new multilocus sequence typing (MLST scheme. This gene-based analysis was compared to genomic characteristics determined by pulsed-field gel electrophoresis (PFGE. METHODOLOGY/PRINCIPAL FINDINGS: The MLST analysis revealed that L. lactis subsp. lactis is essentially clonal with infrequent intra- and intergenic recombination; also, despite its taxonomical classification as a subspecies, it displays a genetic diversity as substantial as that within several other bacterial species. Genome-based analysis revealed a genome size variability of 20%, a value typical of bacteria inhabiting different ecological niches, and that suggests a large pan-genome for this subspecies. However, the genomic characteristics (macrorestriction pattern, genome or chromosome size, plasmid content did not correlate to the MLST-based phylogeny, with strains from the same sequence type (ST differing by up to 230 kb in genome size. CONCLUSION/SIGNIFICANCE: The gene-based phylogeny was not fully consistent with the traditional classification into dairy and non-dairy strains but supported a new classification based on ecological separation between "environmental" strains, the main contributors to the genetic diversity within the subspecies, and "domesticated" strains, subject to recent genetic bottlenecks. Comparison between gene- and genome-based analyses revealed little relationship between core and dispensable genome phylogenies, indicating that clonal diversification and phenotypic variability of the "domesticated" strains essentially arose through substantial genomic flux within the dispensable

  4. Detection and viability of Lactococcus lactis throughout cheese ripening.

    Science.gov (United States)

    Ruggirello, Marianna; Dolci, Paola; Cocolin, Luca

    2014-01-01

    Recent evidences highlighted the presence of Lactococcus lactis during late cheese ripening. For this reason, the role of this microorganism, well known as dairy starter, should be reconsidered throughout cheese manufacturing and ripening. Thus, the main objective of this study was to develop a RT-qPCR protocol for the detection, quantification and determination of the viability of L. lactis in ripened cheese samples by direct analysis of microbial nucleic acids. Standard curves were constructed for the specific quantification of L. lactis in cheese matrices and good results in terms of selectivity, correlation coefficient and efficiency were obtained. Thirty-three ripened cheeses were analyzed and, on the basis of RNA analysis, twelve samples showed 106 to 108 CFU of L. lactis per gram of product, thirteen from 103 to 105 CFU/g, and in eight cheeses, L. lactis was not detected. Traditional plating on M17 medium led to loads ranging from 105 to 109 CFU/g, including the cheese samples where no L. lactis was found by RT-qPCR. From these cheeses, none of the colonies isolated on M17 medium was identified as L. lactis species. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. At the same time, the absence or low abundance of L. lactis isolates on M17 medium from cheese where L. lactis was detected by RT-qPCR support the hypothesis that L. lactis starter populations are mainly present in viable but not culturable state during ripening and, for this reason, culture-dependent methods have to be supplemented with direct analysis of cheese.

  5. Detection and viability of Lactococcus lactis throughout cheese ripening.

    Directory of Open Access Journals (Sweden)

    Marianna Ruggirello

    Full Text Available Recent evidences highlighted the presence of Lactococcus lactis during late cheese ripening. For this reason, the role of this microorganism, well known as dairy starter, should be reconsidered throughout cheese manufacturing and ripening. Thus, the main objective of this study was to develop a RT-qPCR protocol for the detection, quantification and determination of the viability of L. lactis in ripened cheese samples by direct analysis of microbial nucleic acids. Standard curves were constructed for the specific quantification of L. lactis in cheese matrices and good results in terms of selectivity, correlation coefficient and efficiency were obtained. Thirty-three ripened cheeses were analyzed and, on the basis of RNA analysis, twelve samples showed 106 to 108 CFU of L. lactis per gram of product, thirteen from 103 to 105 CFU/g, and in eight cheeses, L. lactis was not detected. Traditional plating on M17 medium led to loads ranging from 105 to 109 CFU/g, including the cheese samples where no L. lactis was found by RT-qPCR. From these cheeses, none of the colonies isolated on M17 medium was identified as L. lactis species. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. At the same time, the absence or low abundance of L. lactis isolates on M17 medium from cheese where L. lactis was detected by RT-qPCR support the hypothesis that L. lactis starter populations are mainly present in viable but not culturable state during ripening and, for this reason, culture-dependent methods have to be supplemented with direct analysis of cheese.

  6. Modeling Lactococcus lactis using a genome-scale flux model

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    Nielsen Jens

    2005-06-01

    Full Text Available Abstract Background Genome-scale flux models are useful tools to represent and analyze microbial metabolism. In this work we reconstructed the metabolic network of the lactic acid bacteria Lactococcus lactis and developed a genome-scale flux model able to simulate and analyze network capabilities and whole-cell function under aerobic and anaerobic continuous cultures. Flux balance analysis (FBA and minimization of metabolic adjustment (MOMA were used as modeling frameworks. Results The metabolic network was reconstructed using the annotated genome sequence from L. lactis ssp. lactis IL1403 together with physiological and biochemical information. The established network comprised a total of 621 reactions and 509 metabolites, representing the overall metabolism of L. lactis. Experimental data reported in the literature was used to fit the model to phenotypic observations. Regulatory constraints had to be included to simulate certain metabolic features, such as the shift from homo to heterolactic fermentation. A minimal medium for in silico growth was identified, indicating the requirement of four amino acids in addition to a sugar. Remarkably, de novo biosynthesis of four other amino acids was observed even when all amino acids were supplied, which is in good agreement with experimental observations. Additionally, enhanced metabolic engineering strategies for improved diacetyl producing strains were designed. Conclusion The L. lactis metabolic network can now be used for a better understanding of lactococcal metabolic capabilities and potential, for the design of enhanced metabolic engineering strategies and for integration with other types of 'omic' data, to assist in finding new information on cellular organization and function.

  7. Mobile CRISPR/Cas-mediated bacteriophage resistance in Lactococcus lactis.

    Directory of Open Access Journals (Sweden)

    Anne M Millen

    Full Text Available Lactococcus lactis is a biotechnological workhorse for food fermentations and potentially therapeutic products and is therefore widely consumed by humans. It is predominantly used as a starter microbe for fermented dairy products, and specialized strains have adapted from a plant environment through reductive evolution and horizontal gene transfer as evidenced by the association of adventitious traits with mobile elements. Specifically, L. lactis has armed itself with a myriad of plasmid-encoded bacteriophage defensive systems to protect against viral predation. This known arsenal had not included CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins, which forms a remarkable microbial immunity system against invading DNA. Although CRISPR/Cas systems are common in the genomes of closely related lactic acid bacteria (LAB, none was identified within the eight published lactococcal genomes. Furthermore, a PCR-based search of the common LAB CRISPR/Cas systems (Types I and II in 383 industrial L. lactis strains proved unsuccessful. Here we describe a novel, Type III, self-transmissible, plasmid-encoded, phage-interfering CRISPR/Cas discovered in L. lactis. The native CRISPR spacers confer resistance based on sequence identity to corresponding lactococcal phage. The interference is directed at phages problematic to the dairy industry, indicative of a responsive system. Moreover, targeting could be modified by engineering the spacer content. The 62.8-kb plasmid was shown to be conjugally transferrable to various strains. Its mobility should facilitate dissemination within microbial communities and provide a readily applicable system to naturally introduce CRISPR/Cas to industrially relevant strains for enhanced phage resistance and prevention against acquisition of undesirable genes.

  8. Strain-Dependent Transcriptome Signatures for Robustness in Lactococcus lactis

    Science.gov (United States)

    Dijkstra, Annereinou R.; Alkema, Wynand; Starrenburg, Marjo J. C.; van Hijum, Sacha A. F. T.; Bron, Peter A.

    2016-01-01

    Recently, we demonstrated that fermentation conditions have a strong impact on subsequent survival of Lactococcus lactis strain MG1363 during heat and oxidative stress, two important parameters during spray drying. Moreover, employment of a transcriptome-phenotype matching approach revealed groups of genes associated with robustness towards heat and/or oxidative stress. To investigate if other strains have similar or distinct transcriptome signatures for robustness, we applied an identical transcriptome-robustness phenotype matching approach on the L. lactis strains IL1403, KF147 and SK11, which have previously been demonstrated to display highly diverse robustness phenotypes. These strains were subjected to an identical fermentation regime as was performed earlier for strain MG1363 and consisted of twelve conditions, varying in the level of salt and/or oxygen, as well as fermentation temperature and pH. In the exponential phase of growth, cells were harvested for transcriptome analysis and assessment of heat and oxidative stress survival phenotypes. The variation in fermentation conditions resulted in differences in heat and oxidative stress survival of up to five 10-log units. Effects of the fermentation conditions on stress survival of the L. lactis strains were typically strain-dependent, although the fermentation conditions had mainly similar effects on the growth characteristics of the different strains. By association of the transcriptomes and robustness phenotypes highly strain-specific transcriptome signatures for robustness towards heat and oxidative stress were identified, indicating that multiple mechanisms exist to increase robustness and, as a consequence, robustness of each strain requires individual optimization. However, a relatively small overlap in the transcriptome responses of the strains was also identified and this generic transcriptome signature included genes previously associated with stress (ctsR and lplL) and novel genes, including nan

  9. Antimicrobial susceptibilities and random amplified polymorphic DNA-PCR fingerprint characterization of Lactococcus lactis ssp. lactis and Lactococcus garvieae isolated from bovine intramammary infections.

    Science.gov (United States)

    Plumed-Ferrer, C; Barberio, A; Franklin-Guild, R; Werner, B; McDonough, P; Bennett, J; Gioia, G; Rota, N; Welcome, F; Nydam, D V; Moroni, P

    2015-09-01

    In total, 181 streptococci-like bacteria isolated from intramammary infections (IMI) were submitted by a veterinary clinic to Quality Milk Production Services (QMPS, Cornell University, Ithaca, NY). The isolates were characterized by sequence analysis, and 46 Lactococcus lactis ssp. lactis and 47 Lactococcus garvieae were tested for susceptibility to 17 antibiotics. No resistant strains were found for β-lactam antibiotics widely used in clinical practice (penicillin, ampicillin, and amoxicillin), and all minimum inhibitory concentrations (MIC) were far from the resistance breakpoints. Eight strains had MIC intermediate to cefazolin. The random amplification of polymorphic DNA (RAPD)-PCR fingerprint patterns showed a slightly higher heterogeneity for Lc. lactis ssp. lactis isolates than for Lc. garvieae isolates.

  10. EFEITO DE PROTETORES E TRATAMENTOS DE ESTRESSE NA SOBREVIVÊNCIA DE LACTOCOCCUS LACTIS SUBSP LACTIS AO CONGELAMENTO Effect of protective and stress treatment on survival of Lactococcus lactis subsp. lactis to freezing

    Directory of Open Access Journals (Sweden)

    Eliana dos Santos Leandro

    2013-02-01

    Full Text Available O efeito de substâncias crioprotetoras e de tratamentos subletais de estresse foi avaliado no aumento da tolerância ao congelamento em Lactococcus lactis subsp lactis PD 6.9. Todas as substâncias crioprotetoras avaliadas aumentaram a sobrevivência de L. lactis subsp lactis PD 6.9 a estocagem de 15 dias a - 20 ºC. Entretanto, o leite desnatado reconstituído a 10 % foi o que conferiu maior proteção. Quanto à exposição da suspensão de células a tratamentos subletais de estresse, a exposição a 10 ºC por 4 horas foi capaz de manter a sobrevivência de L. lactis subsp lactis PD 6.9 estável durante 70 dias de estocagem a - 20 ºC. O tratamento a 40 ºC por 30 minutos conferiu proteção durante 70 dias de estocagem a - 20 ºC quando comparado com a suspensão de células que não recebeu nenhum tratamento antes do congelamento. A aplicação desses tratamentos é importante para assegurar a viabilidade de L. lactis subsp lactis PD 6.9 no decorrer do período de estocagem, e também de assegurar a qualidade sensorial e microbiológica de alimentos obtidos por processos de fermentação.

  11. Comparative genome analysis of Lactococcus garvieae using a suppression subtractive hybridization library: discovery of novel DNA signatures.

    Science.gov (United States)

    Kim, Wonyong; Park, Hee Kuk; Thanh, Hien Dang; Lee, Bo-Young; Shin, Jong Wook; Shin, Hyoung-Shik

    2011-12-01

    Lactococcus garvieae, the pathogenic species in the genus Lactococcus, is recognized as an emerging pathogen in fish, animals, and humans. Despite the widespread distribution and emerging clinical significance of L. garvieae, little is known about the genomic content of this microorganism. Suppression subtractive hybridization was performed to identify the genomic differences between L. garvieae and Lactococcus lactis ssp. lactis, its closest phylogenetic neighbor, and the type species of the genus Lactococcus. Twenty-seven clones were specific to L. garvieae and were highly different from Lactococcus lactis in their nucleotide and protein sequences. Lactococcus garvieae primer sets were subsequently designed for two of these clones corresponding to a pyrH gene and a novel DNA signature for application in the specific detection of L. garvieae. The primer specificities were evaluated relative to three previously described 16S rRNA gene-targeted methods using 32 Lactococcus and closely related strains. Both newly designed primer sets were highly specific to L. garvieae and performed better than did the existing primers. Our findings may be useful for developing more stable and accurate tools for the discrimination of L. garvieae from other closely related species.

  12. Evaluación de la eficacia de dos prescripciones de cepillos dentales en la remoción de placa bacteriana en pacientes ortodóncicos Evaluation of two toothbrushes prescriptions on the removal of plaque in patients with fixed orthodontic appliances

    OpenAIRE

    Zúñiga García,D; EJ Pastén Castro; PA Araya-Díaz; Palomino Montenegro,H

    2012-01-01

    La aparatología empleada en los tratamientos de ortodoncia, favorece la retención de placa bacteriana y dificulta su eliminación por parte del paciente, aumentando el riesgo de desarrollar caries, manchas blancas y enfermedad periodontal. Diferentes cepillos dentales se han desarrollado para facilitar la mantención de una adecuada higiene oral en estos pacientes, sin embargo, se ha observado que los cepillos comunmente indicados (cepillo ortodóncico mas cepillo unipenacho), no siempre son bie...

  13. Perdurabilidad de la efectividad de la combinación penicilina-estreptomicina en la reducción de la carga bacteriana del semen de toro congelado en pastillas (Durability of the effectiveness of the penicillin-streptomycin combination in the reduction of the bacterial content of frozen bulls semen in concentrated pellet form)

    OpenAIRE

    2005-01-01

    Se investigaron por bacteriología general 206 muestras de semen fresco, 133 de semen diluido y congelado en forma de pastillas con adición de penicilina-estreptomicina y 33 sin antibióticos, de diferentes toros de inseminación artificial clínicamente sanos. El resumen de los aislamientos agrupados según las especies bacterianas reveló que las especies más frecuentemente aisladas en muestras de semen fresco fueron E. coli (50,6%), otras enterobacterias (27,7%), Staphylococcus coag. neg. (26,2%...

  14. “VALORACIÓN DE PLACA BACTERIANA Y GINGIVITIS, MEDIANTE EL ÍNDICE DE PLACA DE O ́LEARY E ÍNDICE GINGIVAL DE LOE-SILNESS, POSTERIOR AL USO DE CLORHEXIDINA AL 0.12%, EN PACIENTES CON APARATOLOGIA FIJA”

    OpenAIRE

    Bucio Hernández, María Sugey

    2012-01-01

    Antecedentes: La búsqueda de agentes para el control de la placa bacteriana ha sido amplia, más teniendo en cuenta la importancia que ha adquirido la enfermedad periodontal en los últimos años; esto ha llevado a diversas industrias farmaceuticas a investigar en este campo. En el presente estudio se utilizo el índice Gingival de Löe y Silness (1963), por ser sencillo y valorar todas las áreas del diente, el más utilizado actualmente para medir el estado de inflamación y de salud...

  15. Aportes a la epidemiología de la meningitis bacteriana, Cuba:1998-2007

    OpenAIRE

    Dickinson Meneses, Félix Orlando

    2012-01-01

    En la presente investigación se abordó la epidemiología de la meningitis bacteriana en Cuba sobre la base de 10 años de vigilancia (1998-2007). Streptococcus pneumoniae fue el principal y más letal agente causal, que afectó sobre todo a las edades extremas de la vida y ocasionó una alta letalidad en los adultos y ancianos. La incidencia de la meningitis neumocócica y meningocócica se agrupó en algunos municipios de la región central. Esta última se mantuvo muy baja luego de 20 años de vacu...

  16. Piomiosite bacteriana aguda (PBA em crianças eutróficas

    Directory of Open Access Journals (Sweden)

    Mirtha B. Talavera

    2003-08-01

    Full Text Available A infecção aguda do músculo esquelético é denominada piomiosite bacteriana aguda (PBA. Ocorre mais freqüentemente em regiões tropicais e é mais prevalecente em crianças em idade escolar. A maioria dos casos relatados aconteceu em crianças desnutridas, com parasitoses. Relatamos quatro casos de PBA em crianças previamente eutróficas. A presença de dor muscular aguda localizada, com ou sem sintomas inflamatórios, ocorreu em todos os quatro casos. Osteomielite e/ou artrite séptica também ocorreram em todos os casos. O exame de escolha para o diagnóstico definitivo foi a ressonância nuclear magnética. A terapia foi realizada com antibioticoterapia endovenosa e drenagem cirúrgica dos abscessos.

  17. Assessing the diversity of bacterial communities associated with plants Avaliação da diversidade de comunidades bacterianas associadas às plantas

    Directory of Open Access Journals (Sweden)

    Fernando Dini Andreote

    2009-09-01

    Full Text Available Plant-bacteria interactions result from reciprocal recognition between both species. These interactions are responsible for essential biological processes in plant development and health status. Here, we present a review of the methodologies applied to investigate shifts in bacterial communities associated with plants. A description of techniques is made from initial isolations to culture-independent approaches focusing on quantitative Polymerase Chain Reaction in real time (qPCR, Denaturing Gradient Gel Electrophoresis (DGGE, clone library construction and analysis, the application of multivariate analyses to microbial ecology data and the upcoming high throughput methodologies such as microarrays and pyrosequencing. This review supplies information about the development of traditional methods and a general overview about the new insights into bacterial communities associated with plants.As interações planta-bactéria resultam de um reconhecimento recíproco de ambas espécies. Estas interações são responsáveis por processos biológicos essenciais para o desenvolvimento e a proteção das plantas. Este trabalho revisa as metodologias aplicadas na investigação de alterações nas comunidades bacterianas associadas às plantas. Uma descrição das técnicas é feita, desde o isolamento até a aplicação de técnicas independentes de cultivo, destacando as técnicas de qPCR, Gel de Eletroforese em Gradiente Desnaturante (DGGE, construção e análise de bibliotecas de clones, a aplicação de análise multivariada em dados de ecologia microbiana, e as novas metodologias de alto processamento de amostras como microarranjos e pirosequenciamento. Em resumo, esta revisão fornece informações sobre o desenvolvimento das técnicas tradicionais e uma visão geral sobre as novas tendências dos estudos de comunidades bacterianas associadas às plantas.

  18. Physiological responses of Lactococcus lactis ML3 to alternating conditions of growth and starvation

    NARCIS (Netherlands)

    Kunji, E.R.S.; Ubbink, T.; Matin, A.; Poolman, B.; Konings, W.N.

    1993-01-01

    Lactococcus lactis species can survive periods of carbohydrate starvation for relatively long periods of time. In the first hours of starvation, however, the maximal glycolytic and arginine deiminase (ADI) pathway activities decline rapidly. The rate of decrease of the pathway activities diminishes

  19. Genome-Wide Transcriptional Responses to Carbon Starvation in Nongrowing Lactococcus lactis

    NARCIS (Netherlands)

    Ercan,O.; Wels, M.; Smid. E.J.; Kleerebezem, M.

    2015-01-01

    This paper describes the transcriptional adaptations of nongrowing, retentostat cultures of Lactococcus lactis to starvation. Near-zero-growth cultures (μ = 0.0001 h−1) obtained by extended retentostat cultivation were exposed to starvation by termination of the medium supply for 24 h, followed by a

  20. Lactococcus lactis Uses MscL as Its Principal Mechanosensitive Channel

    NARCIS (Netherlands)

    Folgering, Joost H.A.; Moe, Paul C.; Schuurman-Wolters, Gea K.; Blount, Paul; Poolman, Bert

    2005-01-01

    The functions of the mechanosensitive channels from Lactococcus lactis were determined by biochemical, physiological, and electrophysiological methods. Patchclamp studies showed that the genes yncB and mscL encode MscS and MscL-like channels, respectively, when expressed in Escherichia coli or if th

  1. A Case of Infective Endocarditis and Pulmonary Septic Emboli Caused by Lactococcus lactis

    Science.gov (United States)

    Habib, Adib; Asli, Nazih; Geffen, Yuval; Miron, Dan; Elias, Nael

    2016-01-01

    Infective endocarditis is a rare condition in children with normal hearts. We present here a case of previously healthy eleven-year-old girl with infective endocarditis and pulmonary septic emboli caused by a very rare bacterial etiology (Lactococcus lactis). Identification of this pathogen was only made by polymerase chain reaction.

  2. Hydrophobic membrane thickness and lipid-protein interactions of the leucine transport system of Lactococcus lactis

    NARCIS (Netherlands)

    in t Veld, Gerda; Driessen, Arnold J.M.; Kamp, Jos A.F. op den; Konings, Wil N.

    1991-01-01

    The effect of the phospholipid acyl chain carbon number on the activity of the branched-chain amino acid transport system of Lactococcus lactis has been investigated. Major fatty acids identified in a total lipid extract of L. lactis membranes are palmitic acid (16:0), oleic acid (18:1) and the cycl

  3. Development, molecular characterization and exploitation of the nisin controlled expression system in Lactococcus lactis.

    NARCIS (Netherlands)

    Ruyter, de P.G.G.A.

    1998-01-01

    Lactic acid bacteria are gram-positive bacteria that are widely used in a variety of dairy fermentation processes. Notably, strains of the lactic acid starter bacterium Lactococcus lactis are of great economic importance because of their world-wide use in cheese making. The characteristic aroma, fla

  4. Complete genome sequence of Lactococcus lactis S0, an efficient producer of nisin.

    Science.gov (United States)

    Zhao, Fangyuan; Ma, Hongchu; Lu, Ying; Teng, Kunling; Kang, Xusheng; Wang, Fangfang; Yang, Xiaopan; Zhong, Jin

    2015-03-20

    Lactococcus lactis S0 is a nisin Z-producing strain isolated from milk, and the nisin production of the strain can reach 4000 IU/ml under fermenting condition. Here, we present the complete genome sequence of L. lactis S0 which includes a single circular chromosome.

  5. Properties of Nisin Z and Distribution of Its Gene, nisZ, in Lactococcus lactis

    NARCIS (Netherlands)

    Vos, Willem M. de; Mulders, John W.M.; Siezen, Roland J.; Hugenholtz, Jeroen; Kuipers, Oscar P.

    1993-01-01

    Two natural variants of the lantibiotic nisin that are produced by Lactococcus lactis are known. They have a similar structure but differ in a single amino acid residue at position 27: histidine in nisin A and asparagine in nisin Z. The nisin variants were purified to apparent homogeneity, and their

  6. Complete Genome Sequence of Nonagglutinating Lactococcus garvieae Strain 122061 Isolated from Yellowtail in Japan

    Science.gov (United States)

    Nishiki, Issei; Oinaka, Daisaku; Iwasaki, Yuki; Yasuike, Motoshige; Nakamura, Yoji; Yoshida, Terutoyo; Nagai, Satoshi; Katoh, Masaya; Kobayashi, Takanori

    2016-01-01

    Nonagglutinating Lactococcus garvieae has been isolated from diseased farmed yellowtail in Japan since 2012. In this study, the complete genome and plasmid sequence of nonagglutinating L. garvieae strain 122061 was determined, to our knowledge, for the first time. PMID:27389264

  7. Morphology, genome sequence, and structural proteome of type phage P335 from Lactococcus lactis

    DEFF Research Database (Denmark)

    Labrie, Simon J.; Josephsen, Jytte; Neve, Horst;

    2008-01-01

    Lactococcus lactis phage P335 is a virulent type phage for the species that bears its name and belongs phage P335 is a virulent type phage for the species that bears its name and belongs to the Siphoviridae family. Morphologically, P335 resembled the L. lactis phages TP901-1 and Tuc2009, except...

  8. Genome Sequence of Lactococcus lactis subsp. lactis NCDO 2118, a GABA-Producing Strain

    DEFF Research Database (Denmark)

    Oliveira, Letícia C; Saraiva, Tessália D L; Soares, Siomar C

    2014-01-01

    Lactococcus lactis subsp. lactis NCDO 2118 is a nondairy lactic acid bacterium, a xylose fermenter, and a gamma-aminobutyric acid (GABA) producer isolated from frozen peas. Here, we report the complete genome sequence of L. lactis NCDO 2118, a strain with probiotic potential activity....

  9. A System To Generate Chromosomal Mutations in Lactococcus lactis Which Allows Fast Analysis of Targeted Genes

    NARCIS (Netherlands)

    Law, Jean; Buist, Girbe; Haandrikman, Alfred; Kok, Jan; Venema, Gerhardus; Leenhouts, Kees

    1995-01-01

    A system for generating chromosomal insertions in lactococci is described. It is based on the conditional replication of lactococcal pWV01-derived Ori+ RepA- vector pORI19, containing lacZα and the multiple cloning site of pUC19. Chromosomal AluI fragments of Lactococcus lactis were cloned in pORI19

  10. Characteristics and Osmoregulatory Roles of Uptake Systems for Proline and Glycine Betaine in Lactococcus lactis

    NARCIS (Netherlands)

    Molenaar, Douwe; Hagting, Anja; Alkema, Harmen; Driessen, Arnold J.M.; Konings, Wilhelmus

    1993-01-01

    Lactococcus lactis subsp. lacti ML3 contains high pools of proline or betaine when grown under conditions of high osmotic strength. These pools are created by specific transport systems. A high-affinity uptake system for glycine betaine (betaine) with a Km of 1.5 µM is expressed constitutively. The

  11. Functional Analysis of Promoters in the Nisin Gene Cluster of Lactococcus lactis

    NARCIS (Netherlands)

    Ruyter, Pascalle G.G.A. de; Kuipers, Oscar P.; Beerthuyzen, Marke M.; Alen-Boerrigter, Ingrid van; Vos, Willem M. de

    1996-01-01

    The promoters in the nisin gene cluster nisABTCIPRKFEG of Lactococcus lactis were characterized by primer extension and transcriptional fusions to the Escherichia coli promoterless β-glucuronidase gene (gusA). Three promoters preceding the nisA, nisR, and nisF genes, which all give rise to gusA expr

  12. Rerouting Citrate Metabolism in Lactococcus lactis to Citrate-Driven Transamination

    NARCIS (Netherlands)

    Pudlik, Agata M.; Lolkema, Juke S.

    2012-01-01

    Oxaloacetate is an intermediate of the citrate fermentation pathway that accumulates in the cytoplasm of Lactococcus lactis ILCitM(pFL3) at a high concentration due to the inactivation of oxaloacetate decarboxylase. An excess of toxic oxaloacetate is excreted into the medium in exchange for citrate

  13. Lactococcus lactis Dihydroorotate Dehydrogenase A Mutants Reveal Important Facets of the Enzymatic Function

    DEFF Research Database (Denmark)

    Nørager, Sofie Charlotte; Arent, S; Björnberg, Olof

    2003-01-01

    and 1B, and class 2. This division corresponds to differences in cellular location and the nature of the electron acceptor. Herein we report a study of Lactococcus lactis DHODA, a representative of the class 1A enzymes. Based on the DHODA structure we selected seven residues that are highly conserved...

  14. Transcriptome analysis of the Lactococcus lactis ArgR and AhrC regulons

    DEFF Research Database (Denmark)

    Larsen, Rasmus; van Hijum, Sacha A. F. T.; Martinussen, Jan;

    2008-01-01

    In previous studies, we have shown that direct protein-protein. interaction between the two regulators ArgR and AhrC in Lactococcus lactis is required for arginine-dependent repression of the biosynthetic argC promoter and the activation of the catabolic arcA promoter. Here, we establish the global...

  15. Time-resolved genetic responses of Lactococcus lactis to a dairy environment

    NARCIS (Netherlands)

    Bachmann, H.; Wilt, de L.; Kleerebezem, M.; Hylckama Vlieg, van J.E.T.

    2010-01-01

    Lactococcus lactis is one of main bacterial species found in mixed dairy starter cultures for the production of semi-hard cheese. Despite the appreciation that mixed cultures are essential for the eventual properties of the manufactured cheese the vast majority of studies on L. lactis were carried o

  16. Adaptation of Lactococcus lactis to high growth temperature leads to a dramatic increase in acidification rate

    DEFF Research Database (Denmark)

    Chen, Jun; Shen, Jing; Hellgren, Lars;

    2015-01-01

    Lactococcus lactis is essential for most cheese making, and this mesophilic bacterium has its growth optimum around 30 °C. We have, through adaptive evolution, isolated a mutant TM29 that grows well up to 39 °C, and continuous growth at 40 °C is possible if pre-incubated at a slightly lower...

  17. Heterologous expression and characterization of recombinant Lactococcus lactis neutral endopeptidase (Neprilysin)

    NARCIS (Netherlands)

    Lian, W; Wu, D; Konings, W.N; Mierau, I; Hersh, L.B

    1996-01-01

    A neutral endopeptidase (NEP) from Lactococcus lactis has recently been cloned and shown to contain high sequence homology with the human neutral endopeptidase, endopeptidase 24.11 (I. Mierau et al., J. Bacteriol. 175, 2087-2096, 1993). The gene for the neutral endopeptidase from L. lactis was clone

  18. Characterization of the Lactococcus lactis lactose genes and regulation of their expression.

    NARCIS (Netherlands)

    Rooijen, van R.J.

    1993-01-01

    An important trait of the lactic acid bacterium Lactococcus lactis , that is used in industrial dairy fermentations, is the conversion of lactose into lactic acid. The enzymatic steps involved in the breakdown of lactose, that is transported into the cell via a phosphoenolpyruvate-dependent lactose

  19. Immunogenicity of a malaria parasite antigen displayed by Lactococcus lactis in oral immunisations

    NARCIS (Netherlands)

    Ramasamy, R; Yasawardena, S; Zomer, A; Venema, G; Kok, J; Leenhouts, K

    2006-01-01

    A putative protective protein from Plasmodium falciparum merozoites, MSA2, was expressed in two different ways on the cell surface of the Gram-positive food-grade bacterium, Lactococcus lactis. The first display format exploits an LPXTG-type anchoring motif of the lactococcal proteinase PrtP to cova

  20. Comparative analyses of prophage-like elements present in two Lactococcus lactis strains

    NARCIS (Netherlands)

    Ventura, Marco; Zomer, Aldert; Canchaya, Carlos; O'Connell-Motherway, Mary; Kuipers, Oscar; Turroni, Francesca; Ribbera, Angela; Foroni, Elena; Buist, Girbe; Wegmann, Udo; Shearman, Claire; Gasson, Michael J.; Fitzgerald, Gerald F.; Kok, Jan; van Sinderen, Douwe; O’Connell-Motherway, Mary

    2007-01-01

    In this study, we describe the genetic organizations of six and five apparent prophage-like elements present in the genomes of the Lactococcus lactis subsp. cremoris strains MG1363 and SK11, respectively. Phylogenetic investigation as well bioinformatic analyses indicates that all 11 prophages belon

  1. Molecular analysis of the replication origin of the Lactococcus lactis plasmid pCI305

    NARCIS (Netherlands)

    Foley, S; Bron, S; Venema, G; Daly, C; Fitzgerald, GF

    1996-01-01

    The replication origin region, ori, of the Lactococcus lactis subsp. lactis plasmid pCI305 contains three-and-one-half directly repeated 22-bp sequences and two inverted repeat sequences, IR1 and IR2. These inverted repeat sequences overlap the promoter of the repB gene, which encodes a protein (Rep

  2. Transcriptomic profile of aguR deletion mutant of Lactococcus lactis subsp. cremoris CECT 8666

    NARCIS (Netherlands)

    Del Rio, Beatriz; Linares, Daniel M; Redruello, Begoña; Martin, Maria Cruz; Fernandez, Maria; de Jong, Anne; Kuipers, Oscar P; Ladero, Victor; Alvarez, Miguel A

    2015-01-01

    Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14) is a dairy strain that catabolizes agmatine (a decarboxylated derivative of arginine) into the biogenic amine putrescine by the agmatine deiminase (AGDI) pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, ag

  3. Genotype-phenotype matching analysis of 38 Lactococcus lactis strains using random forest methods

    NARCIS (Netherlands)

    Bayjanov, J.; Starrenburg, M.J.; Sijde, M.R. van der; Siezen, R.J.; Hijum, S.A.F.T. van

    2013-01-01

    BACKGROUND: Lactococcus lactis is used in dairy food fermentation and for the efficient production of industrially relevant enzymes. The genome content and different phenotypes have been determined for multiple L. lactis strains in order to understand intra-species genotype and phenotype diversity a

  4. Topology of LcnD, a protein implicated in the transport of bacteriocins from Lactococcus lactis

    NARCIS (Netherlands)

    Franke, Christian M.; Leenhouts, Kees J.; Haandrikman, Alfred J.; Kok, Jan; Venema, Gerard; Venema, Koen

    1996-01-01

    Four in-frame translational fusions to both the reporter proteins beta-galactosidase and alkaline phosphatase support a topological model of LcnD, a protein implicated in the transport of several bacteriocins from Lactococcus lactis, in which the N-terminal part is located intracellularly and one tr

  5. Quantitative physiology of Lactococcus lactis at extreme low-growth rates

    NARCIS (Netherlands)

    Ercan, O.; Smid, E.J.; Kleerebezem, M.

    2013-01-01

    This paper describes the metabolic adaptation of Lactococcus lactis during the transition from a growing to a non-growing state using retentostat cultivation. Under retentostat cultivation, the specific growth rate decreased from 0.025 h-1 to 0.0001 h-1 in 42 days, while doubling time increased to m

  6. Genome-wide transcriptional responses to carbon starvation in nongrowing Lactococcus lactis

    NARCIS (Netherlands)

    Ercan, O.; Wels, M.; Smid, E.J.; Kleerebezem, M.

    2015-01-01

    This paper describes the transcriptional adaptations of nongrowing, retentostat cultures of Lactococcus lactis to starvation. Near-zero-growth cultures (µ = 0.0001 h-1) obtained by extended retentostat cultivation were exposed to starvation by termination of the medium supply for 24 h, followed by a

  7. Physiological and molecular adaptations of Lactococcus lactis to near-zero growth conditions

    NARCIS (Netherlands)

    Ercan, O.

    2014-01-01

    Lactococcus lactis is an important lactic acid bacteria (LAB) species that is used for the manufacture of dairy products, such as cheese, buttermilk, and other fermented products. The predominant function of this bacterium in dairy fermentation is the production of lactic acid, as its major fermenta

  8. A possible contribution of mRNA secondary structure to translation initiation efficiency in Lactococcus lactis

    NARCIS (Netherlands)

    Guchte, Maarten van de; Lende, Ted van der; Kok, Jan; Venema, Gerard

    1991-01-01

    Gene expression signals derived from Lactococcus lactis were linked to lacZ-fused genes with different 5'-nucleotide sequences. Computer predictions of mRNA secondary structure were combined with lacZ expression studies to direct base-substitutions that could possibly influence gene expression. Muta

  9. Targeting diseases with genetically engineered Lactococcus lactis and its course towards medical translation

    NARCIS (Netherlands)

    Villatoro-Hernandez, Julio; Montes-de-Oca-Luna, Roberto; Kuipers, Oscar P.

    2011-01-01

    The use of the lactic acid bacterium Lactococcus lactis, primarily used in food fermentations, as therapeutic agent is no longer speculative but an imminent reality. After the successful completion of Phase I and II clinical trials in humans for the treatment of inflammatory bowel disease, an ongoin

  10. Effect of X-Prolyl Dipeptidyl Aminopeptidase Deficiency on Lactococcus lactis

    NARCIS (Netherlands)

    Mayo, Baltasar; Kok, Jan; Bockelmann, Wilhelm; Haandrikman, Alfred; Leenhouts, Kees J.; Venema, Gerhardus

    1993-01-01

    The genetic determinant (pepXP) of an X-prolyl dipeptidyl aminopeptidase (PepXP) has recently been cloned and sequenced from both Lactococcus lactis subsp. cremoris (B. Mayo, J. Kok, K. Venema, W. Bockelmann, M. Teuber, H. Reinke, and G. Venema, Appl. Environ. Microbiol. 57:38-44, 1991) and L. lacti

  11. Insertion-Sequence-Mediated Mutations Isolated During Adaptation to Growth and Starvation in Lactococcus lactis.

    NARCIS (Netherlands)

    Visser, de J.A.G.M.; Akkermans, A.D.L.; Hoekstra, R.F.; Vos, de W.M.

    2004-01-01

    We studied the activity of three multicopy insertion sequence (IS) elements in 12 populations of Lactococcus lactis IL1403 that evolved in the laboratory for 1000 generations under various environmental conditions (growth or starvation and shaken or stationary). Using RFLP analysis of single-clone r

  12. Systematic identification of tRNAome and its dynamics in Lactococcus lactis

    NARCIS (Netherlands)

    Puri, Pranav; Wetzel, Collin; Saffert, Paul; Gaston, Kirk W.; Russel, Susan P.; Cordero Varela, Juan A.; van der Vlies, Pieter; Zhang, Gong; Limbach, Patrick A.; Ignatova, Zoya; Poolman, Bert

    2014-01-01

    Transfer RNAs (tRNAs) through their abundance and modification pattern significantly influence protein translation. Here, we present a systematic analysis of the tRNAome of Lactococcus lactis. Using the next-generation sequencing approach, we identified 40 tRNAs which carry 16 different post-transcr

  13. Microbial domestication signatures of Lactococcus lactis can be reproduced by experimental evolution

    NARCIS (Netherlands)

    Bachmann, H.; Starrenburg, M.J.C.; Molenaar, D.; Kleerebezem, M.; Hylckama Vlieg, van J.E.T.

    2012-01-01

    Experimental evolution is a powerful approach to unravel how selective forces shape microbial genotypes and phenotypes. To this date, the available examples focus on the adaptation to conditions specific to the laboratory. The lactic acid bacterium Lactococcus lactis naturally occurs on plants and i

  14. CONTINUOUS MEASUREMENT OF THE CYTOPLASMIC PH IN LACTOCOCCUS-LACTIS WITH A FLUORESCENT PH INDICATOR

    NARCIS (Netherlands)

    MOLENAAR, D; ABEE, T; KONINGS, WN

    1991-01-01

    The cytoplasmic pH of Lactococcus lactis was studied with the fluorescent pH indicator 2',7'-bis-(2-carboxyethyl)-5 (and-6)-carboxyfluorescein (BCECF). A novel method was applied for loading bacterial cells with BCECF, which consists of briefly treating a dense cell suspension with acid in the prese

  15. Construction and Expression of β-galactosidase Genetically Engineered Lactococcus lactis

    Institute of Scientific and Technical Information of China (English)

    吕晓英; 张朝武; 裴晓方; 刘祥; 余倩; 刘衡川

    2004-01-01

    Our objective is to solve the lactose malabsorption and intolerance of human beings by combining mlcro-ecology path with genetic engineering technique. Plasmid pMG36e was used to clone and express a β-galactosidase gene from L.delbrueckii bulgaricus strain 1. 1480 in the Lactococcus lactis subsp, cremoris MG1363 and Lactococcus lactis subsp. lactis IL1403. The recombinant plasmid was preserved and proliferated in Escherichia coli ( E. coli) JM109, and transformed into MG1363 and 1L1403 by electroporation. The protein expression was studied. (1) The bifidobacterium culture medium (BBL) was suitable for the growth of the strain 1. 1480. (2) With 13 amino acids at the N-terminus from the vector, β-galactosidase fusion protein (which retained the enzyme activity) could be successfully expressed in E. coli JM109, MG1363 and IL1403, but the expression quantity was larger in the former than in the latter two. (3) The SD sequence designed could be successfully recognized by both the E. coli and the Lactococcus lactis, but the expression level of the non-fusion β-galac-tosidase protein was lower than that of the fusion protein in the same host. The β-galactosidase genetically engineered E.coli JM109 is a useful tool to produce this enzyme in vitro. The signal peptide of the usp45 protein from the Lactococcus lactis can be added before the promoter sequence to promote β-galactosidase secretion from Lactococcus lactis. The potential application of the β-galactosidase genetically engineered MG1363 and IL1403 to cure the lactose malabsorption and lactose intolerance in both health food and medicine is promising。

  16. Cell wall anchoring of the Campylobacter antigens to Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Patrycja Anna Kobierecka

    2016-02-01

    Full Text Available Campylobacter jejuni is the most frequent cause of human food-borne gastroenteritis and chicken meat is the main source of infection. Recent studies showed that broiler chicken immunization against Campylobacter should be the most efficient way to lower the number of human infections by this pathogen. Induction of the mucosal immune system after oral antigen administration should provide protective immunity to chickens. In this work we tested the usefulness of Lactococcus lactis, the most extensively studied lactic acid bacterium, as a delivery vector for Campylobacter antigens. First we constructed hybrid protein – CjaA antigen presenting CjaD peptide epitopes on its surface. We showed that specific rabbit anti-rCjaAD serum reacted strongly with both CjaA and CjaD produced by a wild type Campylobacter jejuni strain. Next, rCjaAD and CjaA were fused to the C-terminus of the L. lactis YndF containing the LPTXG motif. The genes expressing these proteins were transcribed under control of the L. lactis Usp45 promoter and their products contain the Usp45 signal sequences. This strategy ensures a cell surface location of both analysed proteins, which was confirmed by immunofluorescence assay. In order to evaluate the impact of antigen location on vaccine prototype efficacy, a L. lactis strain producing cytoplasm-located rCjaAD was also generated. Animal experiments showed a decrease of Campylobacter cecal load in vaccinated birds as compared with the control group and showed that the L. lactis harboring the surface-exposed rCjaAD antigen afforded greater protection than the L. lactis producing cytoplasm-located rCjaAD. To the best of our knowledge, this is the first attempt to employ LAB (Lactic Acid Bacteria strains as a mucosal delivery vehicle for chicken immunization. Although the observed reduction of chicken colonization by Campylobacter resulting from vaccination was rather moderate, the experiments showed that LAB strains can be considered

  17. Administração endovenosa de antibióticos e resistência bacteriana: responsabilidade da enfermagem

    Directory of Open Access Journals (Sweden)

    Heloisa Helena Karnas Hoefel

    2006-12-01

    Full Text Available O sucesso da terapêutica com antibióticos e o desenvolvimento da resistência bacteriana dependem de diversos fatores, sendo que os relacionados ao cuidado de enfermagem são o seu preparo e a sua administração. Objetivo: realizar uma revisão da literatura sobre falhas na administração de antibióticos analisando sua possível influência na resistência bacteriana. Delineamento: realizada uma pesquisa bibliográfica das fontes do LILACS e Medline. Métodos: realizada revisão bibliográfica sistematizada com pesquisa de artigos de 1994 a 2005 na Internet usando-se os seguintes descritores juntamente com enfermagem: resistência bacteriana, controle de antibióticos, infecções hospitalares, administração de medicamentos, erros de medicações e eventos adversos. Foram selecionados 58 artigos que apresentaram correlação com a enfermagem e/ou eram básicos na fundamentação brasileira ou internacional. Resultados: Foram descritos aspectos gerais sobre a resistência bacteriana, antibióticos e custos incluindo estratégias para prevenção da resistência e classificações de erros utilizadas internacionalmente. Conclusões: Baseado nesse conhecimento são recomendadas intervenções para implementação do cuidado de enfermagem prático e seguro.

  18. Candida albicans skin abscess Abscesso de pele por Candida albicans

    Directory of Open Access Journals (Sweden)

    Felipe Francisco Tuon

    2006-10-01

    Full Text Available Subcutaneous candidal abscess is a very rare infection even in immunocompromised patients. Some cases are reported when breakdown in the skin occurs, as bacterial cellulites or abscess, iatrogenic procedures, trauma and parenteral substance abuse. We describe a case of Candida albicans subcutaneous abscess without fungemia, which can be associated with central venous catheter.Abscesso subcutâneo por Candida é infecção muito rara mesmo em pacientes imunocomprometidos. Alguns casos são relatados quando ocorre dano na pele, como celulite bacteriana ou abscesso, procedimentos iatrogênicos, trauma e abuso de substância parenteral. Relatamos caso de abscesso subcutâneo por Candida albicans sem fungemia, que pode estar associado com cateter venoso central.

  19. Guías de manejo de las queratitis infecciosas bacterianas. Hospital Universitario del Valle, enero-julio 2002 .

    Directory of Open Access Journals (Sweden)

    Alejandro de La Torre

    2009-11-01

    Full Text Available Propósito. Evaluar los resultados de la aplicación de las guías de manejo de las queratitis infecciosas bacterianas en pacientes que llegan al Servicio de Oftalmología. Métodos. Ingresaron con diagnóstico de queratitis infecciosas bacterianas 21 pacientes durante 6 meses. Resultados. De 18 queratitis infecciosas, 16 (88.9% se manejaron medicamente y 2 se les realizó tratamiento quirúrgico; 50% (9 se diagnosticaron como severas, 14 cumplieron criterios para tomar muestras de laboratorio: sensibilidad del Gram es de 50% y la sensibilidad de cultivos para bacterias es de 64.2%. La bacteria encontrada con más frecuencia fue el Staphylococcus epidermidis. Conclusión. El estudio demostró evidentemente que las guías de manejo propuestas para las queratitis infecciosas bacterianas son útiles para lograr su recuperación sin complicaciones (prueba exacta de Fisher p= 0.001032.

  20. Purification and partial characterization of bacteriocin produced by Lactococcus lactis ssp. lactis LL171.

    Science.gov (United States)

    Kumari, Archana; Akkoç, Nefise; Akçelik, Mustafa

    2012-04-01

    Lactic acid bacteria (LAB) are possessing ability to synthesize antimicrobial compounds (like bacteriocin) during their growth. In this regard, novel bacteriocin compound secreting capability of LAB isolated from Tulum Cheese in Turkey was demonstrated. The synthesized bacteriocin was purified by ammonium sulphate precipitation, dialysis and gel filtration. The molecular weight (≈3.4 kDa) of obtained bacteriocin was confirmed by SDS-PAGE, which revealed single peptide band. Molecular identification of LAB strain isolated from Tulum Cheese was conducted using 16S rDNA gene sequencing as Lactococcus lactis ssp. lactis LL171. The amino acid sequences (KKIDTRTGKTMEKTEKKIELSLKNMKTAT) of the bacteriocin from Lactococcus lactis ssp. lactis LL171 was found unique and novel than reported bacteriocins. Further, the bacteriocin was possessed the thermostable property and active at wide range of pH values from 1 to 11. Thus, bacteriocin reported in this study has the potential applications property as food preservative agent.

  1. Biosorption of silver cations onto Lactococcus lactis and Lactobacillus casei isolated from dairy products

    Science.gov (United States)

    Milanowski, Maciej; Pomastowski, Paweł; Railean-Plugaru, Viorica; Rafińska, Katarzyna; Ligor, Tomasz; Buszewski, Bogusław

    2017-01-01

    The current work deals with the phenomenon of silver cations uptake by two kinds of bacteria isolated from dairy products. The mechanism of sorption of silver cations by Lactococcus lactis and Lactobacillus casei bacteria was investigated. Inductively coupled plasma–mass spectrometry (ICP-MS) was used for determination of silver concentration sorbed by bacteria. Analysis of charge distribution was conducted by diffraction light scattering method. Changes in the ultrastructure of Lactococcus lactis and Lactobacillus casei cells after treatment with silver cations were investigated using transmission electron microscopy observation. Molecular spectroscopy methods, namely Fourier transform-infrared spectroscopy (FT-IR) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) were employed for description of the sorption mechanism. Moreover, an analysis of volatile organic compounds (VOCs) extracted from bacterial cells was performed. PMID:28362838

  2. PURIFICATION AND CHARACTERIZATION OF NISIN PRODUCED BY LACTOCOCCUS LACTIS ISOLATED FROM INDIAN CURD

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    Saba A. Mahdy

    2015-12-01

    Full Text Available Lactococcus lactis isolated from traditional dairy Indian curd. Strains were preliminarily identified by PCR analysis and partial 16S rRNA confirmed that N5 were 100% identical to Lactococcus. lactis sp. lactis. The results revealed that only the bacteriocin produced from strain N5 was shown as being active against mostly gram positive bacteria The bacteriocin produced purified by precipitation followed by loading with gel chromatography. The partially purified bacteriocin was found to be stable over a wide range of pH, temperature and enzymes. The molecular weight of the peptide was judged to be 3.5 kDa by SDSpolyacrylamide gel electrophoresis.and conform to the result of mass spectrometry by maldi-tof test which calculated the mass of 3354.07 Da for nisin.These results indicate that bacteriocin produced by L. lactis sp. lactis N5 is a nisin.

  3. Physiological and regulatory effects of controlled overproduction of five cold shock proteins of Lactococcus lactis

    NARCIS (Netherlands)

    Wouters, J.A.; Mailhes, M.; Rombouts, F.M.; Vos, de W.M.; Kuipers, O.P.; Abee, T.

    2000-01-01

    The physiological and regulatory effects of overproduction of five cold shock proteins (CSPs) of Lactococcus lactis were studied. CspB, CspD, and CspE could be overproduced at high levels (up to 19␘f the total protein), whereas for CspA and CspC limited overproduction (0.3 to 0.5␘f the total protein

  4. In vivo imaging of Lactococcus lactis, Lactobacillus plantarum and Escherichiacoli expressing infrared fluorescent protein in mice

    OpenAIRE

    Berlec, Aleš; Štrukelj, Borut; Završnik, Janja; Turk, Boris; Butinar, Miha

    2016-01-01

    Background In vivo imaging of orally administered lactic acid bacteria (LAB) and commensal bacteria in mice is shown to provide information on the spatial and temporal distribution of bacteria in the gastrointestinal tract. The bacteria can be detected and monitored using bioluminescence or near-infrared fluorescence. Results Fluorescence imaging of bacteria was established by expressing the infrared fluorescent protein IRFP713 in Lactococcus lactis, Lactobacillus plantarum and Escherichia co...

  5. Generation of Dipeptidyl Peptidase-IV-Inhibiting Peptides from β-Lactoglobulin Secreted by Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Suguru Shigemori

    2014-01-01

    Full Text Available Previous studies showed that hydrolysates of β-lactoglobulin (BLG prepared using gastrointestinal proteases strongly inhibit dipeptidyl peptidase-IV (DPP-IV activity in vitro. In this study, we developed a BLG-secreting Lactococcus lactis strain as a delivery vehicle and in situ expression system. Interestingly, trypsin-digested recombinant BLG from L. lactis inhibited DPP-IV activity, suggesting that BLG-secreting L. lactis may be useful in the treatment of type 2 diabetes mellitus.

  6. Development, molecular characterization and exploitation of the nisin controlled expression system in Lactococcus lactis.

    OpenAIRE

    Ruyter, de, D.J.

    1998-01-01

    Lactic acid bacteria are gram-positive bacteria that are widely used in a variety of dairy fermentation processes. Notably, strains of the lactic acid starter bacterium Lactococcus lactis are of great economic importance because of their world-wide use in cheese making. The characteristic aroma, flavor and texture of cheese develops during ripening of the cheese curd through the action of numerous enzymes derived from the cheese milk, the coagulant, and the starter and non-starter bacteria. R...

  7. Characterization of the Lactococcus lactis lactose genes and regulation of their expression.

    OpenAIRE

    Rooijen, van, J.

    1993-01-01

    An important trait of the lactic acid bacterium Lactococcus lactis , that is used in industrial dairy fermentations, is the conversion of lactose into lactic acid. The enzymatic steps involved in the breakdown of lactose, that is transported into the cell via a phosphoenolpyruvate-dependent lactose phosphotransferase system (PEP-PTS lac), have been well established (Fig. 1). However, except for the molecular cloning and characterization of the plasmid-located phospho-B-galactosidase gene (Boi...

  8. Milk fermentation by Lactococcus lactis with modified proteolytic systems to accumulate potentially bio-active peptides

    OpenAIRE

    Algaron, Florence; Miranda, Guy; Le Bars, Dominique; Monnet, Véronique

    2004-01-01

    International audience; The proteolytic system of lactic acid bacteria has been characterised in detail and numerous modified strains with null or increased specific proteolytic activities have been constructed or identified among natural strains. Based on this knowledge, our objective was to ferment milk with modified strains and produce mixtures of peptides with specific features corresponding to potential bio-activities. We used a collection of Lactococcus lactis negative mutants for pepti...

  9. Diagnóstico clínico, de laboratorio y tratamiento de la vaginosis por Gardnerella vaginilis

    OpenAIRE

    JOSÉ ANTONIO SÁNCHEZ HERNÁNDEZ; LAURA LIZETH COYOTECATL GARCÍA; ESTHER VALENTÍN GONZÁLEZ; LIZZET VERA GORDILLO; JOSÉ ANTONIO RIVERA TAPIA

    2007-01-01

    La vaginosis bacteriana es la infección de tejidos vaginales, generalmente por transmisión sexual, en cambio la vaginitis es la inflamación de la mucosa de la vagina y obedece a diversas etiologías. La vaginosis es más frecuente durante el periodo fértil y aunque su etiología es polimicrobiana se ha visto que uno de los agentes infecciosos más importante es Gardnerella vaginalis; identificada en la década de 1950 por Leopod, Gardner y Dukes, los que después de varios estudios la encontraron e...

  10. Patrones de resistencia bacteriana en urocultivos en un hospital oncológico Antimicrobial resistance patterns of isolates from urine cultures at an oncological center

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    Patricia Cornejo-Juárez

    2007-10-01

    Full Text Available OBJETIVOS: Describir los patrones de resistencia bacteriana en cultivos de orina en un hospital oncológico. MATERIAL Y MÉTODOS: Se incluyeron las cepas obtenidas de cultivos de orina de 1998 a 2005. Se obtuvo el porcentaje de sensibilidad para diferentes antibióticos, tras analizar por separado cepas nosocomiales y compararlas con las de la comunidad. RESULTADOS: Se detectaron 9 232 cultivos positivos (20.7% de 44 447 muestras: gramnegativos, 78.8%; grampositivos, 13.8%; y levaduras, 7.4 por ciento. Escherichia coli fue el principal microorganismo identificado (41.3%; la resistencia en aislados nosocomiales fue mayor que en la comunidad para amikacina (92.4 y 97%, ceftazidima (83.1 y 95.1% y ciprofloxacina (46.2 y 58.6%. De igual manera, Pseudomonas aeruginosa presentó mayor resistencia para amikacina y ceftazidima en las cepas nosocomiales (55.7 y 66.6%; y 65.5 y 84.8%, respectivamente. Enterococcus resistente a vancomicina se encontró sólo en 2.5% (3/119 aislados de E. faecium. CONCLUSIONES: Existe una mayor resistencia bacteriana en las cepas de origen nosocomial en comparación con las cepas comunitarias. Se encontró un incremento progresivo de la resistencia para E. coli, el patógeno aislado con más frecuencia de infecciones nosocomiales y comunitarias. Es prioritario intensificar una campaña educativa para el control y uso racional de los antibióticos.OBJECTIVE: To describe the patterns of antimicrobial resistance of organisms isolated from urine cultures at a teaching oncological hospital for adult patients. MATERIAL AND METHODS: All strains obtained from urine cultures from 1998 to 2005 were included. Mean susceptibilities were obtained for each antimicrobial tested; nosocomial and community-acquired isolates were analyzed separately. RESULTS: A total of 9 232 positive urine cultures were obtained (20.7% from 44 447 samples taken. Gram negative bacteria were reported in 78.8%, Gram-positive in 13.8% and yeasts in 7

  11. Etiologia e evolução das meningites bacterianas em centro de pediatria Etiology and evolution of bacterial meningitis in a pediatric center

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    Roberta M.C. Romanelli

    2002-02-01

    Full Text Available Objetivo: determinar a prevalência dos agentes etiológicos das meningites bacterianas em serviço de referência, no atendimento de doenças infecciosas para o estado de Minas Gerais, e verificar a resposta ao tratamento utilizado.Métodos: estudo descritivo em que foram incluídas todas as crianças com diagnóstico provável de meningite, admitidas na instituição no período de junho a novembro/99.Resultados: obteve-se 210 casos de meningite, sendo 111 casos de etiologia bacteriana (52,9%. Destes, 52 casos foram diagnósticos prováveis (por alteração do liquor rotina e 59 com diagnósticos de certeza (por cultura e/ou isolamento de antígeno. Os principais agentes isolados foram, em ordem decrescente, H. influenzae, N. meningitidis e S. pneumoniae. O tratamento inicial para a faixa etária de três meses a cinco anos foi ampicilina e cloranfenicol, sendo posteriormente restrito para penicilina em casos de meningococo e pneumococo, e para cloranfenicol nos casos de H. influenzae. A mudança para antimicrobiano de maior espectro foi realizada com base em dados clínicos ou laboratoriais, não havendo isolamento de microorganismo resistente.Conclusões: o acompanhamento do perfil epidemiológico das meningites deve ser contínuo, e cada serviço deve se basear em dados locais para direcionar a terapia antimicrobiana. A monitorização contínua dos agentes prevalentes em cada instituição e de sua resistência é fundamental para a escolha antimicrobiana, atuando com menor interferência na colonização individual, sem contribuir para a crescente resistência dos agentes responsáveis pelas infecções meníngeas.Objective: to establish the prevalence of the etiological agents of bacterial meningitis in a reference center for the treatment of infectious diseases in the state of Minas Gerais. Methods: descriptive study including all children with probable diagnosis of meningitis between June/1999 and November/1999.Results: there were 210

  12. Relación placa bacteriana y caries en un grupo de niños escolarizados entre 5 y 14 años de la población de la Boquilla - Cartagena en el año 20041

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    Lizelia Alfaro Zolá

    2013-10-01

    Full Text Available Objetivo: Describir la ocurrencia de placa bacteriana en las superficies dentales y relacionarla con el tipo de lesión de caries que se presenta en niños escolares de 5 a 14 años de la Boquilla - Cartagena. Materiales y Métodos: Se realizó un estudio de corte transversal, en el cual se seleccionó una muestra de 89 niños escolares de la población de la Boquilla a través de un muestreo aleatorio sistemático, a quienes se les evaluó el estado de higiene oral mediante el índice de placa comunitario de Corchuelo modificado y el índice de caries superficial con criterios de diagnóstico Ekstrand. Resultados: La superficie con lesiones de caries de mayor frecuencia fue la oclusal, presentándose un mayor numero de lesiones detenidas, seguido en palatino por las lesiones precavitacionales, a diferencia de las superficies vestibular y lingual donde se encontraron un mayor número de superficies sanas. En todas las superficies evaluadas predominó la presencia de placa bacteriana independientemente de la presencia de caries y no se encontró una relación estadísticamente significativa entre estas dos variables. Conclusiones: La alta frecuencia de placa bacteriana en las superficies dentarias nos mostró el deficiente estado de higiene oral de la población, sin embargo, sigue en duda la pertinencia de los índices de placa para la predicción de la caries debido a que no se encontró relación estadística. (Duazary 2007; 2: 119 - 126

  13. Medición de cambios cuantitativos de la microbiota subgingival posterior a la remoción de placa bacteriana supragingival Measurement of quantitative changes of the microbiota subgingival after to removal of bacterial plaque supragingival

    Directory of Open Access Journals (Sweden)

    C Godoy

    2010-04-01

    Full Text Available Uno de los campos de interés en el estudio de la microbiología periodontal para muchos investigadores ha sido identificar si es posible que los microorganismos responsables del origen y progresión de la enfermedad periodontal que habitan sobre el margen gingival (supragingival y bajo este (subgingival tengan una relación directa que permita mantener interacciones influyentes en el crecimiento y desarrollo de las diferentes especies bacterianas que habitan en los tejidos periodontales. Por lo tanto, al remover los microorganismos que se ubican supragingivalmente sería posible encontrar cambios en el medio subgingival al no existir un intercambio entre los ambientes aerobios (supragingival y anaerobios (subgingival una vez desorganizada la placa bacteriana supragingival. Para demostrar esta relación se seleccionaron 7 individuos con diagnóstico de periodontitis crónica moderada y severa a los cuales se les realizó un destartraje supragingival de boca completa para lograr desorganizar la placa bacteriana supragingival. A su vez se tomaron muestras microbiológicas de los sacos periodontales más profundos de cada cuadrante de estos individuos, siendo la primera muestra tomada previo al destartraje supragingival considerada como muestra basal (día 0, luego se tomaron a las 24 horas, a los 7 y 21 días de removida la placa bacteriana supragingival. De los resultados del presente estudio pudimos concluir que al desorganizar el biofilm supragingival se observa una disminución en la cantidad total de microorganismos subgingivales, así como también disminuye de manera considerable la proporción de Porphyoromona gingivalis presente en el medio subgingival. Lo cual permitiría establecer la existencia de una relación directa y dependiente entre los microorganismos que habitan el medio supragingival y subgingival.One of the fields of interest in the study of the microbiology periodontal for many investigators has been to identify if it is

  14. Sepsis por Acinetobacter baumannii multirresistente: a propósito de un caso

    OpenAIRE

    Hernández Blanco, Javier Enrique; Arrieta Aguilera, Ana Milena; Arcón Medina, Dewitt Fabián; Castellano Orcasita, Juan Enrique

    2012-01-01

    En este artículo se revisa el caso clínico de un paciente con cuadro de infección nosocomial por Acinetobacter baumannii multirresistente, quien a pesar del tratamiento instaurado presentó deterioro de su condición clínica. Se realiza una revisión bibliográfica en diversas bases de datos con el fin de mencionar actualizaciones en el tema y describir el mecanismo de acción antibiótica y resistencia bacteriana que ha dificultado en los últimos años el manejo de estos pacientes. http://revist...

  15. Detecção da adição fraudulenta de soro de queijo em leite: interferência da atividade de proteases bacterianas.

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    Gislene Bremer de Oliveira

    2009-06-01

    Full Text Available Uma das fraudes econômicas mais comumente aplicadas ao leite fluido é a adição do soro de queijo. A ocorrência dessa fraude, no Brasil, é sugerida pela análise do índice de caseinomacropeptídeo (CMP, uma porção da molécula de ê-caseína solúvel no soro. No entanto, a ação de proteases produzidas por microrganismos psicrotróficos pode interferir neste teste levando a resultados falso-positivos, situação que passou a ter maior importância após a implementação da Instrução Normativa 51 (2002. Com o objetivo de avaliar esta interferência, foi inoculado no leite ca6 103 UFC/mL de Pseudomonas spp. seguido de incubação durante 2 e 5 dias a 7 ºC. O crescimento microbiano foi monitorado e, após estes períodos, o leite foi submetido a tratamento térmico (100 ºC/5 min para eliminação das células bacterianas e o extrato enzimático foi obtido para posterior análise da atividade de proteases. Em seguida, o leite foi submetido à incubação 30 ºC/30 d e o índice de CMP foi analisado nos tempos zero e 30 dias. Os resultados dos testes de atividade de proteases após 2 dias de incubação, usando como substrato a azocaseína, não diferiram significativamente (P > 0,05 dos de 5 dias. Diferentemente, os índices de CMP no tempo zero do tratamento 5d/7 ºC para o leite inoculado com P. fluorescens, foram maiores do que o mesmo leite fraudado com 30% de soro de queijo, o que denota ainda mais a necessidade de controlar este importante deteriorante. Após 30 dias houve diminuição destes índices, possivelmente em decorrência da degradação do próprio CMP pelas proteases produzidas por P. fluorescens.

  16. Infecciones en pacientes hospitalizados por cirrosis Infections in hospitalized patients with cirrhosis

    Directory of Open Access Journals (Sweden)

    Sebastián Mathurin

    2009-04-01

    Full Text Available Evaluamos la prevalecencia y relevancia clínica de las infecciones bacterianas y no bacterianas en pacientes cirróticos predominantemente alcohólicos internados en un hospital de mediana complejidad, y comparamos las características clínicas, de laboratorio y la evolución de pacientes con y sin infección bacteriana en un estudio prospectivo de cohorte. Se incluyeron 211 internaciones consecutivas de 132 pacientes con diagnóstico de cirrosis, de abril 2004 a julio 2007. El promedio de edad (±DS fue 51.8 (±8 años, 112 fueron hombres (84.8%; etiología alcohólica 95.4%. Se diagnosticaron 129 episodios de infecciones bacterianas en 99/211 (46.9% internaciones, adquiridos en la comunidad 79 (61.2% y 50 (38.8% intrahospitalarios: peritonitis bacteriana espontánea (23.3%; infección urinaria (21.7%; neumonías (17.8%; infecciones de piel y partes blandas (17.1%; sepsis por bacteriemia espontánea (7.7%; otras infecciones bacterianas (12.4%. El 52.2% fueron por gérmenes gram-positivos. Hubo ocho casos de tuberculosis e infecciones graves por hongos y parásitos. La prevalecencia de tuberculosis fue del 6% con una mortalidad anual de 62.5%. El 28.1% (9/32 de los exámenes coproparasitológicos tuvieron Strongyloides stercolaris. La mortalidad hospitalaria fue mayor en los pacientes con infección bacteriana (32.4% vs. 13.2%; p=0.02. Fueron identificados como predictores independientes de mortalidad: las infecciones bacterianas, el score de Child-Pügh y creatininemia > 1.5 mg/dl. En el análisis multivariado fueron factores independientes asociados a infección bacteriana la leucocitosis y la encefalopatía hepática grado III/IV. Este estudio confirma que las infecciones bacterianas y no bacterianas son una complicación frecuente y grave en pacientes cirróticos internados, con un aumento de la mortalidad hospitalaria.We evaluated the prevalence and the clinical relevance of bacterial and nonbacterial infections in predominantly alcoholic

  17. Lactococcus lactis NCC 2287 Alleviates Food Allergic Manifestations in Sensitized Mice by Reducing IL-13 Expression Specifically in the Ileum

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    Adrian W. Zuercher

    2012-01-01

    Full Text Available Objective. Utilizing a food allergy murine model, we have investigated the intrinsic antiallergic potential of the Lactococcus lactis NCC 2287 strain. Methods. BALB/c mice were sensitized at weekly intervals with ovalbumin (OVA plus cholera toxin (CT by the oral route for 7 weeks. In this model, an oral challenge with a high dose of OVA at the end of the sensitization period leads to clinical symptoms. Lactococcus lactis NCC 2287 was given to mice via the drinking water during sensitization (prevention phase or after sensitization (management phase. Results. Lactococcus lactis NCC 2287 administration to sensitized mice strikingly reduced allergic manifestations in the management phase upon challenge, when compared to control mice. No preventive effect was observed with the strain. Lactococcus lactis NCC 2287 significantly decreased relative expression levels of the Th-2 cytokine, IL-13, and associated chemokines CCL11 (eotaxin-1 and CCL17 (TARC in the ileum. No effect was observed in the jejunum. Conclusion/Significance. These results taken together designate Lactococcus lactis NCC 2287 as a candidate probiotic strain appropriate in the management of allergic symptoms.

  18. Lactococcus lactis NCC 2287 Alleviates Food Allergic Manifestations in Sensitized Mice by Reducing IL-13 Expression Specifically in the Ileum

    Science.gov (United States)

    Zuercher, Adrian W.; Weiss, Marietta; Holvoet, Sébastien; Moser, Mireille; Moussu, Hélène; van Overtvelt, Laurence; Horiot, Stéphane; Moingeon, Philippe; Nutten, Sophie; Prioult, Guénolée; Singh, Anurag; Mercenier, Annick

    2012-01-01

    Objective. Utilizing a food allergy murine model, we have investigated the intrinsic antiallergic potential of the Lactococcus lactis NCC 2287 strain. Methods. BALB/c mice were sensitized at weekly intervals with ovalbumin (OVA) plus cholera toxin (CT) by the oral route for 7 weeks. In this model, an oral challenge with a high dose of OVA at the end of the sensitization period leads to clinical symptoms. Lactococcus lactis NCC 2287 was given to mice via the drinking water during sensitization (prevention phase) or after sensitization (management phase). Results. Lactococcus lactis NCC 2287 administration to sensitized mice strikingly reduced allergic manifestations in the management phase upon challenge, when compared to control mice. No preventive effect was observed with the strain. Lactococcus lactis NCC 2287 significantly decreased relative expression levels of the Th-2 cytokine, IL-13, and associated chemokines CCL11 (eotaxin-1) and CCL17 (TARC) in the ileum. No effect was observed in the jejunum. Conclusion/Significance. These results taken together designate Lactococcus lactis NCC 2287 as a candidate probiotic strain appropriate in the management of allergic symptoms. PMID:21961022

  19. Diversity analysis of dairy and nondairy Lactococcus lactis isolates, using a novel multilocus sequence analysis scheme and (GTG)5-PCR fingerprinting

    NARCIS (Netherlands)

    Rademaker, J.L.W.; Herbet, H.; Starrenburg, M.J.C.; Naser, S.M.; Gevers, D.; Kelly, W.J.; Hugenholtz, J.; Swings, J.; van Hylckama Vlieg, J.E.T.

    2007-01-01

    The diversity of a collection of 102 lactococcus isolates including 91 Lactococcus lactis isolates of dairy and nondairy origin was explored using partial small subunit rRNA gene sequence analysis and limited phenotypic analyses. A subset of 89 strains of L. lactis subsp. cremoris and L. lactis subs

  20. Genética y genómica enfocadas en el estudio de la resistencia bacteriana

    OpenAIRE

    Ulises Garza-Ramos; Jesús Silva-Sánchez; Esperanza Martínez-Romero

    2009-01-01

    La resistencia bacteriana es un problema de salud pública causante de índices elevados de morbi-mortalidad hospitalaria. En la medida en que se usan los diferentes antibióticos se seleccionan bacterias resistentes a múltiples fármacos. El desarrollo de nuevas herramientas moleculares de la genómica y proteómica, como el PCR en tiempo real, pirosecuenciación de ADN, espectrometría de masas, microarreglos de ADN y bioinformática, permite conocer en forma más estrecha la fisiología y estructura ...

  1. Avaliação da resistência de clones e cultivares de batata à murcha bacteriana (Ralstonia solanacearum)

    OpenAIRE

    Lima Neto, Artur Ferreira

    2005-01-01

    Cultivares e clones de batata (Solanum tuberosum L.) foram avaliados de 2002 a 2004 na Embrapa Hortaliças, Brasília-DF, para resistência à murcha bacteriana em campo naturalmente infestado com a raça 1, biovar 1 de Ralstonia solanacearum. Os testes de avaliação foram conduzidos com as cultivares atualmente mais plantadas no Brasil e com conjuntos de clones relatados como resistentes no Brasil e em outras partes do mundo. Em todos os experimentos, a doença foi avaliada pela incidência de plant...

  2. Estudo prospectivo dos fatores de risco para complicações neurológicas na meningite bacteriana infantil

    Directory of Open Access Journals (Sweden)

    Sadie Namani

    2013-06-01

    Full Text Available OBJETIVO: Análise prospectiva de fatores de prognóstico para complicações neurológicas da meningite bacteriana infantil. MÉTODOS: Este estudo prospectivo recrutou 77 crianças de um mês a 16 anos de idade tratadas de meningite bacteriana durante o período de 1/1/2009 a 31/12/2010. Foram escolhidos 16 preditores relevantes para analisar sua associação com a incidência de complicações neurológicas. Valores P abaixo de 0,05 foram considerados estatisticamente significativos. RESULTADOS: Das 77 crianças tratadas para meningite bacteriana, desenvolveram-se complicações neurológicas em 33 pacientes (43%, e duas crianças morreram (2,6%. A etiologia dos casos de meningite bacteriana foi comprovada em 57/77 (74% dos casos: foram encontrados 32 isolados de meningococos; 8 de pneumococos; 6 de bacilos gram-negativos; 5 de H. influenzae; 5 de estafilococos e 1 de S. viridans. Os fatores que se mostraram associados a aumento do risco de desenvolvimento de complicações neurológicas foram idade 5.000 células/mm³, pleiocitose > 5.000 células/mm³ depois de 48 horas, baixa relação da glicose no LCS/sangue 48 horas, presença de comorbidade e foco primário de infecção não se associaram a aumento do risco para o desenvolvimento de complicações neurológicas. CONCLUSÃO: Idade inferior a 12 meses e gravidade da apresentação clínica na admissão foram identificadas como os preditores mais fortes de complicações neurológicas e podem ter valor para selecionar pacientes para tratamento mais intensivo.

  3. O uso de antibióticos e as resistências bacterianas: breves notas sobre a sua evoluc¸ão

    OpenAIRE

    Loureiro, Rui João; Roque, Fátima; Teixeira-Rodrigues, António; Herdeiro, Maria Teresa; Ramalheirae, Elmano

    2016-01-01

    A resistência bacteriana aos antibióticos é atualmente um dos problemas de saúde pública mais relevantes a nível global, dado que apresenta consequências clínicas e económicas preocupantes, estando associada ao uso inadequado de antibióticos. Portugal é, no contexto europeu, um país com um elevado consumo de antibióticos, apesar de uma diminuic¸ão no consumo destes fármacos nos últimos anos. A resistência bacteriana tem crescido acentuadamente, sendo que as bactérias Gram-posit...

  4. Etiologia e evolução das meningites bacterianas em centro de pediatria Etiology and evolution of bacterial meningitis in a pediatric center

    OpenAIRE

    Roberta M.C. Romanelli; Claudete A. Araújo; Fernando Boucinhas; Carvalho,Inácio R.; Nelson R.L. Martins; Heliane B. M. Freire

    2002-01-01

    Objetivo: determinar a prevalência dos agentes etiológicos das meningites bacterianas em serviço de referência, no atendimento de doenças infecciosas para o estado de Minas Gerais, e verificar a resposta ao tratamento utilizado.Métodos: estudo descritivo em que foram incluídas todas as crianças com diagnóstico provável de meningite, admitidas na instituição no período de junho a novembro/99.Resultados: obteve-se 210 casos de meningite, sendo 111 casos de etiologia bacteriana (52,9%). Destes, ...

  5. Aderência bacteriana in vitro a lentes intra-oculares de polimetilmetacrilato e de silicone In vitro bacterial adherence to silicone and polymetylmethacrylate intraocular lenses

    Directory of Open Access Journals (Sweden)

    Claudete Inês Locatelli

    2004-04-01

    Full Text Available OBJETIVOS: Verificar a aderência bacteriana a lentes intra-oculares de silicone e de polimetilmetacrilato como possível fator de risco no desenvolvimento de endoftalmite pós-operatória, utilizando-se um modelo in vitro com três microrganismos potencialmente patogênicos. MÉTODOS: As análises foram realizadas com cepas de Staphylococcus aureus ATCC 29213, Staphylococcus epidermidis (amostra clínica e Pseudomonas aeruginosa ATCC 27853 incluindo a determinação de curvas de crescimento, testes para verificação de produção de cápsula, avaliação da hidrofobicidade, testes de aderência a diferentes materiais, microscopia óptica, microscopia eletrônica de varredura e microscopia de força atômica. RESULTADOS: A produção de cápsula e a aderência das três diferentes cepas não mostraram qualquer relação com a quantidade de microrganismos; em relação às lentes intra-oculares de polimetilmetacrilato e de silicone, não houve diferença estatisticamente significativa na aderência de S. aureus e S. epidermidis; P. aeruginosa foi o microrganismo mais aderente a ambos os materiais. A microscopia eletrônica de varredura confirmou estes achados em relação à aderência, ao peso que a microscopia de força atômica evidenciou a produção de biofilme pelas cepas de S. aureus, S. epidermidis e P. aeruginosa. CONCLUSÕES: Constatou-se, in vitro, que os materiais analisados não diferiram com relação à taxa de aderência bacteriana, porém, P. aeruginosa apresentou maior eficiência de adesão entre as bactérias testadas. Todas as cepas produziram biofilme. Silicone foi o material mais hidrofóbico, quando comparado ao polimetilmetacrilato.PURPOSE: To evaluate bacterial adherence to silicone and polymetylmethacrylate (PMMA intraocular lenses as a risk factor for postsurgery endophthalmitis by using an in vitro model with three potentially pathogenic microorganisms. METHODS: In vitro experiments were carried out with the

  6. Control of Brochothrix thermosphacta in pork meat using Lactococcus lactis subsp. lactis I23 isolated from beef

    Directory of Open Access Journals (Sweden)

    Olusegun A Olaoye

    2015-06-01

    Full Text Available This study evaluated the antimicrobial activities of two lactic acid bacteria (LAB Lactococcus lactis subsp. lactis I23 and L. lactis subsp. hordinae E91 against Brochothrix thermosphacta in pork during storage at ambient temperature (30oC over 7 days. Both the LAB strains and spoilage organism were inoculated on fresh pork samples at 1x106cfu/g. About 3 log reduction in the spoilage organism was obtained in LAB treated samples after 48 h of storage. The spoilage organism was confirmed to be sensitive to the bacteriocin nisin produced by Lactococcus lactis subsp. lactis I23. There were reductions in the counts of Salmonella typhimurium, Listeria monocytogenes, Enterobacteriaceae and Staphylococcus in the treated samples. Conclusively, growth of B. thermosphacta could be effectively controlled by nisin producing Lactococcus lactis subsp. lactis I23 in fresh pork during storage, thereby enhancing shelf life of the product.

  7. Identification of Lactococcus-Specific Bacteriocins Produced by Lactococcal Isolates, and the Discovery of a Novel Bacteriocin, Lactococcin Z.

    Science.gov (United States)

    Ishibashi, Naoki; Seto, Hiromi; Koga, Shoko; Zendo, Takeshi; Sonomoto, Kenji

    2015-09-01

    Lactic acid bacteria that produce Lactococcus-specific bacteriocins were isolated and identified as Lactococcus lactis from fresh corn or lettuce. Among them, four isolates were identified as lactococcin Q producers. Seven isolates showed antimicrobial activity against a lactococcin Q producer, L. lactis QU 4, as well as against nisin Z and lacticin Q producers belonging to L. lactis. Strain QU 7 was selected as a standard strain and showed no cross-immunity to lactococcin Q or other lactococcal bacteriocins. The bacteriocin produced by strain QU 7 was purified in three chromatographic steps, and its molecular mass was determined to be 5041.35 Da. The amino acid sequence analysis revealed that it is a novel class IId bacteriocin, referred to as lactococcin Z. It consisted of 45 amino acid residues. The lczA gene encoding the prepeptide of lactococcin Z showed homology to lactococcins A, B, and M. Thus, this report demonstrates a new example of Lactococcus-specific bacteriocins.

  8. Perfil clínico e microbiológico de mulheres com vaginose bacteriana Clinical and microbiological profile of women with bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    Sonia Regina Ribeiro de Figueiredo Leite

    2010-02-01

    Full Text Available OBJETIVO: estudar o perfil clínico e microbiológico de mulheres portadoras de vaginose bacteriana participantes de um ensaio clínico randomizado, duplamente mascarado, que comparou aroeira e metronidazol, em uso vaginal, para tratamento do corrimento genital. MÉTODOS: o estudo constitui-se em uma série de casos de 277 mulheres portadoras de vaginose bacteriana diagnosticada, concomitantemente, pelos critérios de Amsel e Nugent, selecionadas a partir de um total de 462 recrutadas, utilizando as informações colhidas antes da intervenção. A análise dos dados foi efetuada utilizando-se o programa Epi-Info 3.32. Para comparar as frequências dos desfechos entre os grupos de intervenção, foi utilizado o teste do χ2 e foi calculada a razão de risco e o intervalo de confiança a 95%. Foi feita análise por intenção de tratar. Além dos parâmetros de diagnósticos, foram também colhidas cultura do conteúdo vaginal e uma citologia de Papanicolaou. RESULTADOS: entre as queixas clínicas, as mais frequentes foram o corrimento genital, observado em 206 participantes (74,4% e o odor de peixe da secreção vaginal, que ocorreu em 68,6% dos casos (190 pacientes. Dentre os critérios clínicos de diagnósticos, a presença de clue-cells foi positiva em 275 mulheres (99,3%, o teste de Whiff positivo apareceu em 266 participantes (96,0%, seguido do pH >4,5, que ocorreu em 92,8% dos casos e da presença de corrimento fluido e acinzentado, citado por 206 participantes (74,4%. Com relação ao critério de Nugent, a mediana dos escores foi o valor 8,0. As culturas de conteúdo vaginal permitiram a identificação de Gardnerella vaginalis em 96,8% e de Mobiluncus, em 53,1% dos casos. Apenas uma terça parte dos exames mostrou a presença de Lactobacillus (89 mulheres - 32,1%. Houve crescimento de fungos em culturas de 14 participantes (5,1%. Na maior parte dos casos, os resultados das culturas demonstraram a presença de Corynebacterium (94

  9. por valores

    Directory of Open Access Journals (Sweden)

    Jazmín Díaz-Barrios

    2005-01-01

    Full Text Available La era actual se caracteriza por una búsqueda de la identidad del hombre, donde el pivote del cambio organizacional es el individuo; cambiar en este entorno depende, en gran medida, de los valores que imperen en la cultura de la organización. Este trabajo documental intenta identificar aquellos valores, condición sine-qua-non, para el logro de los objetivos de cambio y analizarlos a fin de determinar sus indicadores, con el objeto de presentar una herramienta a las organizaciones que les facilite adaptarse a los nuevos tiempos. Se encontró que los valores: Delegación, Comunicación, Colaboración, Participación y Aprendizaje, son esenciales en los cambios integrales de esta era. Se determinaron 20 indicadores de su presencia. Se concluye que con esta información cada ente puede elaborar instrumentos que le permitan saber si los valores requeridos están presentes y en caso contrario tomar decisiones que alineen a la organización alrededor de los valores humanistas planteados, incrementando así las posibilidades de éxito en el proceso de cambio y por ende, las posibilidades de supervivencia en esta nueva época.

  10. Latex agglutination vs. counterimmunoelectrophoresis in the diagnosis of acute bacterial meningitis Aglutinación de partículas de látex vs. contrainmunoelectroforesis en meningitis bacteriana aguda

    Directory of Open Access Journals (Sweden)

    Witer Elena Vallejo López

    1991-01-01

    Full Text Available

    A comparison was made between latex particles agglutination (LPA and counterimmunoelectrophoresis (CIE in the diagnosis of 57 children with acute bacterial meningitis; reagents were utllized to detect infection by Haemophilus influenzae, Streptococcus pneumoniae and Neísseria meningitídís. Results of both tests were similar for diagnosis of H. ínfluenzae and S. pneumoniae; in contrast only 30.0% of cases due to N. meningitidis gave a positive result with LP A and none was detected with CIE.in 12 patients (21.0% LPA and CIE were the only tests that allowed a precise determination ot the etiology of the disease. The authors recommend LPA for the particular situation of limited availability of funds since it is more economic than CIE and the quality of the results is similar.

    Se estudiaron 57 pacientes con meningitis aguda, de etiología bacteriana comprobada; 47.4% (27 casos fueron causados por Haemophilus influenzae tipo b; 21.0% (12 casos por Streptococcus pneumoniae; 17.5% (10 casos por Neisseria meningitidis; 5.3% (3 casos por Staphylococcus aureus,. 5.3% (3 casos por enterobacterias y 3.5% (2 casos por gérmenes no Identificados por cultivos. Se comparó la aglutinación de partículas de látex (APL con la contralnmunoelectroforesis (CIE en los pacientes con cultivo positivo. La exactitud de ambas fue similar para el H. influenzae tipo b y el S. pneumoniae. Tres de los 10 casos con cultivo positivo para N. meningítidis fueron positivos en la APL pero ninguno lo fue en la CIE. Se presentó un falso positivo para H. ínfluenzae con la APL que correspondió a meningitis por Salmonella typhí, Las pruebas inmunológicas estuvieron plenamente justificadas en 12 de los 57 pacientes (21.0%, previamente tratados, en quienes la bacteriología tradicional fue negativa o se quería identificar el germen porque lo único positivo era el gram y se justificaba utilizar el

  11. Fatores de risco para meningite bacteriana no recém-nascido Risk factors for bacterial meningitis in the newborn

    Directory of Open Access Journals (Sweden)

    Vera Lúcia Jornada Krebs

    2004-09-01

    Full Text Available O objetivo do estudo é descrever os fatores de risco para meningite bacteriana em recém-nascidos e analisar a prevalência destes fatores, considerando-se a presença ou não de baixo peso ao nascimento. Foram analisados 50 recém-nascidos com meningite bacteriana, excluindo-se aqueles com meningomielocele ou infecção congênita. Na análise estatística utilizou-se o teste exato de Fisher, considerando-se significantes os valores de p The aim of this study is to describe the risk factors for bacterial meningitis in newborns, and to analyze the prevalence of these factors, considering or not the low birth weight presence. Fifty newborns with bacterial meningitis were analyzed, excluding the ones with meningomyelocele or congenital infection. In the statistical analysis, the Fisher's exact test was used, considering significant the p < 0.05 values. This study has shown that prematurity, low birth weight and presence of previous infectious diseases in the newborn or in the mother were important risk factors for meningitis. Among low birth weight newborns, invasive procedures, especially tracheal intubation, use of central venous catheter and previous use of antibiotics, were significantly associated to the meningitis occurrence. These results indicate that the improvement in the prenatal care and in the hospital infection control are measures of high importance in the decrease of the incidence of neonatal bacterial meningitis.

  12. Inoculação de suspensão bacteriana de Plesiomonas shigelloides em Jundiá, Rhamdia quelen (Teleostei: Pimelodidae Inoculation of bacterial suspension of Plesiomonas shigelloides in jundiá, Rhamdia quelen (Teleostei: Pimelodidae

    Directory of Open Access Journals (Sweden)

    Cheila de Lima Boijink

    2001-06-01

    Full Text Available Com o crescimento da aqüicultura mundial e intensificação da criação de peixes, os animais ficam sujeitos às enfermidades bacterianas e outras. Com o objetivo de avaliar a patogenicidade da Plesiomonas shigelloides para jundiás (Rhamdia quelen, diferentes concentrações bacterianas (3 x 10(8 e 9 x 10(8 UFC - Unidade Formadora de Colônia/ml foram inoculadas por via intraperitoneal. Foram utilizados 84 jundiás juvenis com peso e comprimento médios de 24,37 ± 4,28g e 14,42 ± 1,62cm, respectivamente. Os animais inoculados foram mantidos durante 21 dias, em caixas d'agua de amianto, em condições semelhantes de temperatura, pH, alcalinidade e dureza. Os jundiás foram sacrificados a cada dois dias para contagem de UFC/ml de tecido renal. Por observações diárias, constatou-se que a inoculação intraperitoneal de Plesiomonas shigelloides não ocasionou nenhuma alteração nos jundiás, independente da concentração inoculada. As contagens das bactérias nos rins dos jundiás mantiveram-se entre 10(5 e 10(6UFC/ml até o 21º dia, quando o experimento foi finalizado.As worldwide aquaculture has grown, and intensification in fish raising, the animals are subject to bacterial diseases and others. With the aim of evaluating pathogenicity of Plesiomonas shigelloides for "jundiá" (Rhamdia quelen, different bacterial concentrations (3 x 10(8 e 9 x 10(8 CFU - Colony Former Unit/ml were inoculated via peritoneum. Eigthy four juvenile "jundiá" averaging 24.37 ± 4,28g of weight and 14.42 ± 1,62cm of length were utilized. The inoculated animals were maintained for 21 days, in asbestos water tanks, at similar temperature, pH, alkalinity and hardness conditions. The "jundiás" were slaughtered every other day for counting UFC/ml renal tissue. For daily inspections, it was observed that intraperitoneal inoculation of Plesiomonas shigelloides did not cause any change in the catfishes, regardless inoculated concentration. Bacteria counting in

  13. Phosphoglycerate Mutase Is a Highly Efficient Enzyme without Flux Control in Lactococcus lactis

    DEFF Research Database (Denmark)

    Solem, Christian; Petranovic, D.; Købmann, Brian

    2010-01-01

    The glycolytic enzyme phosphoglycerate mutase (PGM), which catalyzes the conversion of 3-phosphoglycerate to 2-phosphoglycerate, was examined in Lactococcus lactis with respect to its function, kinetics and glycolytic flux control. A library of strains with PGM activities ranging between 15......-465% of the wild-type level was constructed by replacing the native promoter of pgm with synthetic promoters of varying strengths. The specific growth rate and glucose flux were found to be maximal at the wild-type level at which PGM had no flux control. Low flux control of PGM was found on mixed acid fluxes...

  14. Non-Fusion and Fusion Expression of β-Galactosidase from Lactobacillus bulgaricus in Lactococcus lactis

    Institute of Scientific and Technical Information of China (English)

    CHUAN WANG; CHAO-WU ZHANG; HENG-CHUAN LIU; QIAN YU; XIAO-FANG PEI

    2008-01-01

    Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion. Methods The gene fragments encoding β-galactosidase from two strains of Lactobacillus bulgaricus, wch9901 isolated from yogurt and 1.1480 purchased from the Chinese Academy of Sciences, were amplified and inserted into lactococcal expression vector pMG36e. For fusion expression, the open reading frame of the β-galactosidase gene was amplified, while for non-fusion expression, the open reading frame of the β-galactosidase gene was amplified with its native Shine-Dalgarno sequence upstream. The start codon of the β-galactosidase gene partially overlapped with the stop codon of vector origin open reading frame. Then, the recombinant plasmids were transformed into Escherichia coli DH5α and Lactococcus lactis subsp, lactis MG1363 and confirmed by determining β-galactosidase activities. Results The non-fusion expression plasmids showed a significantly higher β-galactosidase activity in transformed strains than the fusion expression plasmids. The highest enzyme activity was observed in Lactococcus lactis transformed with the non-fusion expression plasmids which were inserted into the β-galactosidase gene from Lactobacillus bulgaricus wch9901. The β-galactosidase activity was 2.75 times as high as that of the native counterpart. In addition, β-galactosidase expressed by recombinant plasmids in Lactococcus lactis could be secreted into the culture medium. The highest secretion rate (27.1%) was observed when the culture medium contained 20 g/L of lactose. Conclusion Different properties of the native bacteria may have some effects on the protein expression of recombinant plasmids. Non-fusion expression shows a higher enzyme activity in host bacteria. There may be a ost-related weak secretion signal peptide gene within the structure gene of Lb

  15. Mechanism of flavin reduction in the class 1A dihydroorotate dehydrogenase from Lactococcus lactis

    DEFF Research Database (Denmark)

    Fagan, Rebecca L; Jensen, Kaj Frank; Björnberg, Olof;

    2007-01-01

    is concerted or stepwise was addressed for the class 1A enzyme from Lactococcus lactis by determining kinetic isotope effects (KIEs) on flavin reduction in anaerobic stopped-flow experiments. Isotope effects were determined at two pH values. At pH 7.0, KIEs were approximately 2-fold for DHO labeled singly...... mutants was extremely slow compared to that of the wild type; the rate of reduction increased with pH, showing no sign of a plateau. Interestingly, double-deuterium isotope effects on the Cys130Ser mutant also showed a concerted mechanism for flavin reduction....

  16. Cloning and Characterization of upp, a Gene Encoding Uracil Phosphoribosyltransferase from Lactococcus lactis

    DEFF Research Database (Denmark)

    Martinussen, Jan; Hammer, Karin

    1994-01-01

    Uracil phosphoribosyltransferase catalyzes the key reaction in the salvage of uracil in many microorganisms. The gene encoding uracil phosphoribosyltransferase (upp) was cloned from Lactococcus lactis subsp. cremoris MG1363 by complementation of an Escherichia coli mutant. The gene was sequenced...... construction of an internal deletion, a upp mutant was constructed by a double-crossover event. This implicated the utilization of a plasmid with a thermosensitive origin of replication and a new and easy way to screen for double crossover events in both gram-positive and gram-negative bacterial strains...

  17. Lactococcus lactis-based vaccines from laboratory bench to human use: an overview.

    Science.gov (United States)

    Bahey-El-Din, Mohammed

    2012-01-17

    Developing effective vaccines is an important weapon in the battle against potential pathogens and their evolving antibiotic resistance trends. Several vaccine delivery vectors have been investigated among which the generally regarded as safe (GRAS) Lactococcus lactis has a distinguished position. In this review, different factors affecting the efficacy of L. lactis-based vaccines are discussed. In addition, the issues of biological containment and pharmaceutical quality assurance of L. lactis vaccines are highlighted. These issues are critical for the success of medical translation of L. lactis-based vaccines from research laboratories to clinical use by ensuring consistent manufacturing of safe and efficacious vaccines.

  18. Cloning and Expression of the Lactococcus lactis purDEK Genes, Required for Growth in Milk

    DEFF Research Database (Denmark)

    Nilsson, Dan; Kilstrup, Mogens

    1998-01-01

    An operon containing the genes purD and purE and part of the purK gene was cloned from the facultative anaerobic gram positive bacterium Lactococcus lactis by complementation of the purD mutation in Escherichia coli SO609. The genes encode enzymes in the de novo pathway of purine nucleotides....... The expression of the genes was regulated approximately 35-fold at the transcription level by the availability of purines in the growth medium. Deletion analysis of the nucleotide region upstream of purD indicated that a region of 145 bp is enough to give regulated expression of the reporter lacLM genes, which...

  19. Metabolic behavior of Lactococcus lactis MG1363 in microaerobic continuous cultivation at a low dilution rate

    DEFF Research Database (Denmark)

    Jensen, Niels B.S.; Melchiorsen, Claus Rix; Jochumsen, Kirsten Væver;

    2001-01-01

    Minute amounts of oxygen were supplied to a continuous cultivation of Lactococcus lactis subsp. cremoris MG1363 grown on a defined glucose-limited medium at a dilution rate of 0.1 h(-1). More than 80% of the carbon supplied with glucose ended up in fermentation products other than lactate. Addition...... dioxide and acetate to replace formate and ethanol as catabolic end products while hardly affecting the production of either acetoin or lactate. The negative impact of oxygen on the synthesis of pyruvate formate lyase was confirmed. Moreover, oxygen was shown to down regulate the protein level of alcohol...

  20. Complete genome sequence and description of Lactococcus garvieae M14 isolated from Algerian fermented milk

    Directory of Open Access Journals (Sweden)

    M. Moumene

    2016-03-01

    Full Text Available We describe using a polyphasic approach that combines proteomic by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF analysis, genomic data and phenotypic characterization the features of Lactococcus garvieae strain M14 newly isolated from the fermented milk (known as raib of an Algerian cow. The 2 188 835 bp containing genome sequence displays a metabolic capacity to form acid fermentation that is very useful for industrial applications and encodes for two bacteriocins responsible for its eventual bioprotective properties.

  1. Prevalencia de vaginosis bacteriana y factores asociados en veinte ciudades del Perú

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    Lorena López-Torres

    Full Text Available Objetivos. Determinar la prevalencia de vaginosis bacteriana (VB y factores asociados en mujeres peruanas de 18 a 29 años de edad en 20 ciudades a partir de datos del proyecto PREVEN. Materiales y métodos. Estudio de tipo transversal, la definición de VB se realizó previa selección de una muestra de secreción vaginal en una lámina portaobjetos. Las láminas fueron teñidas usando la tinción Gram para ser observadas al microscopio usando el puntaje de Nugent, el diagnóstico de VB se aplicó a los puntajes 7-10. Se estimaron razones de prevalencias (RP y sus intervalos de confianza al 95% (IC 95% mediante el uso de modelos lineales generalizados. Resultados. Un total de 6322 mujeres contestaron la encuesta epidemiológica y proporcionaron muestras vaginales. La prevalencia de VB fue de 23,7% (IC95%: 22,6-24,7 y se asoció con tener un mayor número de parejas sexuales en los últimos 12 meses (RP: 1,22, IC 95%: 1,03-1,44, p=0,020; para dos parejas y RP: 1,46, IC 95%: 1,23-1,74, p<0,001 para tres o más parejas, no usar condón en la última relación sexual (RP: 1,16, IC 95%: 1,01-1,34, p=0,034, ser residente de la sierra (RP: 1,18, IC 95%: 1,05-1,31, p=0,004 y tener flujo vaginal anormal o con mal olor (RP: 1,20, IC 95%: 1,09-1,33, p<0,001. Conclusiones. La alta prevalencia de VB encontrada remarca la necesidad de fortalecer los servicios de salud para la detección y tratamiento de esta condición.

  2. Efecto de la sacarosa en la producción de celulosa por Gluconacetobacter xylinus en cultivo estático

    OpenAIRE

    Rubén Jaramillo L; Wladimir Tobio J.; José Escamilla M.

    2012-01-01

    RESUMENObjetivo. Determinar el efecto de sacarosa en la productividad de BC por Gluconacetobacter xylinus IFO 13693 en condición estática. Materiales y métodos. La síntesis de celulosa bacteriana (BC) por Gluconacetobacter xylinus se llevo a cabo en un cultivo estático discontinuo a temperatura ambiente, en presencia de sacarosa como la principal fuente de carbono a concentraciones iniciales de 0.8 a 7.6 % (p/v). Las concentraciones remanentes de BC, sacarosa, glucosa y fructosa se determinar...

  3. Evaluación de la resistencia bacteriana frente a tres antibióticos usados en la maduración del camarón marino (Litopenaeus vannamei).

    OpenAIRE

    Luna G., Diana; De León L., Jorge; Vallejo I., Adriana; Velásquez L., Gustavo

    2003-01-01

    La incidencia de las enfermedades bacteriana en camaronicultura, ha conducido a la utilización de terapéuticos, con el subsecuente problema de generación de resistencia a mediano y largo plazo, afectando la producción. Con el objetivo de evaluar la resistencia bacteriana en un sistema de maduración de Litopenaeus vannamei , fueron aisladas 18 cepas bacterianas correspondientes a V. parahaemolyticus (n=3), V. alginolyiticus (n=5), V. hollisae (n=5) y Flavobacterium spp. (n=5). ...

  4. Antibacterial effects of medicinal plant extracts against Lactococcus garvieae, the etiological agent of rainbow trout lactococcosis

    Directory of Open Access Journals (Sweden)

    Mohammad Saeid Fereidouni

    2013-05-01

    Full Text Available Eight medicinal plants were assessed for antimicrobial activity against Lactococcus garvieae isolate obtained from diseased Oncorhynchus mykiss collected from rainbow trout fish farms in Iran. Lactococcus garvieae is among the major pathogens of a large number of fish species cultured in fresh and marine recirculating and net pen production systems. The antibacterial activity of the medicinal plants against L. garvieae was evaluated using disc diffusion, well diffusion and minimum inhibitory concentration. Results showed that the extracts and essential oils had a relatively high antibacterial activity against L. garvieae. Of the plants studied, the most active extracts were those from the methanol extract of Peganum harmala, the essential oil of Satureja bachtiarica, the ethanol extract of Juglans regia and Trachyspermum copticum with minimum inhibitory concentration (MIC of 105, 126, 510 and 453 μg/ml, respectively. Conversly, some of the extracts such as Quercus branti Lindley and Glycyrrhiza glabra L. had lower activity against L. garvieae with MIC values of 978 and 920 μg/ml respectively. Plant extracts as natural and environment- friendly compounds can be an important source of antibacterial agents against L. garvieae. They may be used for disinfection of instruments and rainbow trout raceways or treatment of the fish.

  5. First Case Report of a Late Onset Knee Periprosthetic Joint Infection Caused by Lactococcus garvieae

    Directory of Open Access Journals (Sweden)

    V.-I. Neagoe

    2016-01-01

    Full Text Available Lactococcus garvieae is known as a Gram-positive, catalase-negative, and facultatively anaerobic fish pathogen. The association between Lactococcus spp. and human infectious diseases is described as being mainly associated with lumbar osteomyelitis, hepatic abscess, and infective endocarditis. In the literature of orthopedic post-prosthetic infections, L. garvieae was associated with a case of hip prosthetic infection in a fishmonger woman. We present the case of a 79-year-old male patient with multiple comorbidities, who is admitted to our center with a 5-day history of pain, swelling, and motility disorder of the right knee by the presence of a bicondylar knee replacement surgery, which was performed due to gonarthrosis 17 years ago. The radiographies of the right knee revealed no signs of displacement or loosening of the prothesis. After multiple radical debridements including VAC therapy and targeted antibiotic therapy we have managed to defeat the infection without exchange arthroplasty. Although we could not demonstrate the source of infection, we can only presume that in our case the source of infection was represented by the ingestion of possibly contaminated food. The patient had a habit of eating Nile perch fish (Lates niloticus every 4 weeks. We illustrated once more the possibility of a late onset L. garvieae related orthopedic periprosthetic joint infection by multiple comorbidities.

  6. Analysis of the genome content of Lactococcus garvieae by genomic interspecies microarray hybridization

    Directory of Open Access Journals (Sweden)

    Gibello Alicia

    2010-03-01

    Full Text Available Abstract Background Lactococcus garvieae is a bacterial pathogen that affects different animal species in addition to humans. Despite the widespread distribution and emerging clinical significance of L. garvieae in both veterinary and human medicine, there is almost a complete lack of knowledge about the genetic content of this microorganism. In the present study, the genomic content of L. garvieae CECT 4531 was analysed using bioinformatics tools and microarray-based comparative genomic hybridization (CGH experiments. Lactococcus lactis subsp. lactis IL1403 and Streptococcus pneumoniae TIGR4 were used as reference microorganisms. Results The combination and integration of in silico analyses and in vitro CGH experiments, performed in comparison with the reference microorganisms, allowed establishment of an inter-species hybridization framework with a detection threshold based on a sequence similarity of ≥ 70%. With this threshold value, 267 genes were identified as having an analogue in L. garvieae, most of which (n = 258 have been documented for the first time in this pathogen. Most of the genes are related to ribosomal, sugar metabolism or energy conversion systems. Some of the identified genes, such as als and mycA, could be involved in the pathogenesis of L. garvieae infections. Conclusions In this study, we identified 267 genes that were potentially present in L. garvieae CECT 4531. Some of the identified genes could be involved in the pathogenesis of L. garvieae infections. These results provide the first insight into the genome content of L. garvieae.

  7. Tulum Peynirlerinden izole Edilen Lactococcus lactis subsp. lactis YBML9 ve

    Directory of Open Access Journals (Sweden)

    Yasin TUNCER

    2009-04-01

    Full Text Available Bu çalısmanın amacı tulum peynirlerinden izole edilen Lactococcus lactis suslarının fenotipik tanısı ve bu suslar tarafından üretilen bakteriyosinlerin kısmi karakterizasyonlarıdır. Bu amaçla Türkiye'nin sekiz farklı ilinden (Ankara, Antalya, Burdur, Denizli, Erzincan, Isparta, İstanbul ve İzmir yöresel pazarlardan toplanan 60 adet tulum peyniri örneginden 40 adet Lactococcus lactis susu (31 adet L. lactis subsp. lactis ve 9 adet L. lactis subsp. cremoris izole edildi. 40 adet L. lactis susu içerisinden, 2 adet L. lactis subsp. lactis (YBML9 ve YBML21 susu bakteriyosin üretme yeteneginde bulundu. L. lactis subsp. lactis YBML9 ve YBML21 susları tarafından üretilen bakteriyosinler, farklı enzim, pH ve sıcaklık uygulamaları sonucu; sırasıyla nisin ve laktisin 481 olarak tanımlandı.

  8. POTENTIAL OF Lactococcus lactis subsp. lactis MTCC 3041 AS A BIOPRESERVATIVE

    Directory of Open Access Journals (Sweden)

    Neha Sharma

    2013-10-01

    Full Text Available Lactic acid bacteria especially in developing countries can be exploited against frequently occurring spoilage organisms of fresh fruits and vegetables in addition to pathogens. Keeping in views this antagonism imparted by bacteria Lactococci, the present study was taken and effectiveness of bacteriocin of Lactococci was also studied in preservatives and enzymes. Lactic acid bacteria Lactococcus lactis subs. Lactis MTCC 3041 was used as bacteriocin producer strain. Isolation of most frequently occurring spoilage organisms from spoiled Mango and Kinnow was done by microbiological procedures and were identified by microscopic studies as Isolate 1 and Isolate 2. It has limited use in processed salted food as no zone of inhibition was observed at and above 5% NaCl (w/v.0.3% (w/v is the minimum concentration of KMS that provides stress to the microorganism for the production of bacteriocin. It is not suitable for food having sodium benzoate as preservative as with increase in concentration growth of Lactococcus lactis decreases. Presence of bacteriocin hinders the growth of the isolate 1 as fresh weight of the mycelium in test sample is 7.09% less than the control. Being non-pathogenic this organism can be safely used against spoilage organisms in addition to food borne pathogens.

  9. Enhancing bile tolerance improves survival and persistence of Bifidobacterium and Lactococcus in the murine gastrointestinal tract

    Directory of Open Access Journals (Sweden)

    Hill Colin

    2008-10-01

    Full Text Available Abstract Background The majority of commensal gastrointestinal bacteria used as probiotics are highly adapted to the specialised environment of the large bowel. However, unlike pathogenic bacteria; they are often inadequately equipped to endure the physicochemical stresses of gastrointestinal (GI delivery in the host. Herein we outline a patho-biotechnology strategy to improve gastric delivery and host adaptation of a probiotic strain Bifidobacterium breve UCC2003 and the generally regarded as safe (GRAS organism Lactococcus lactis NZ9000. Results In vitro bile tolerance of both strains was significantly enhanced (P Listeria monocytogenes bile resistance mechanism BilE. Strains harbouring bilE were also recovered at significantly higher levels (P n = 5, following oral inoculation. Furthermore, a B. breve strain expressing bilE demonstrated increased efficacy relative to the wild-type strain in reducing oral L. monocytogenes infection in mice. Conclusion Collectively the data indicates that bile tolerance can be enhanced in Bifidobacterium and Lactococcus species through rational genetic manipulation and that this can significantly improve delivery to and colonisation of the GI tract.

  10. Classification of Lactococcus lactis cell envelope proteinase based on gene sequencing, peptides formed after hydrolysis of milk, and computer modeling

    DEFF Research Database (Denmark)

    Børsting, Mette Winther; Qvist, K.B.; Brockmann, E.

    2015-01-01

    Lactococcus lactis strains depend on a proteolytic system for growth in milk to release essential AA from casein. The cleavage specificities of the cell envelope proteinase (CEP) can vary between strains and environments and whether the enzyme is released or bound to the cell wall. Thirty-eight L...

  11. Interaction between ArgR and AhrC controls regulation of arginine metabolism in Lactococcus lactis

    NARCIS (Netherlands)

    Larsen, R; Kok, J; Kuipers, OP

    2005-01-01

    The expression of arginine metabolism in Lactococcus lactis is controlled by the two homologous transcriptional regulators ArgR and AhrC. Genome sequence analyses have shown that the occurrence of multiple homologues of the ArgR family of transcriptional regulators is a common feature of many low-G

  12. Two nucleoside uptake systems in Lactococcus lactis: Competition between purine nucleosides and cytidine allows for modulation of intracellular nucleotide pools

    DEFF Research Database (Denmark)

    Martinussen, Jan; Wadskov-Hansen, Steen Lyders Lerche; Hammer, Karin

    2003-01-01

    in Lactococcus lactis were investigated by measuring the uptake of radioactively labeled nucleosides. The K. for for inosine, cytidine, and uridine was determined to be in the micromolar range. Furthermore, it was found that cytidine and inosine are competitive inhibitors of each other, whereas no competition...

  13. Physiological and Regulatory Effects of Controlled Overproduction of Five Cold Shock Proteins of Lactococcus lactis MG1363

    NARCIS (Netherlands)

    Wouters, Jeroen A.; Mailhes, Marielle; Rombouts, Frank M.; Vos, Willem M. de; Kuipers, Oscar P.; Abee, Tjakko

    2000-01-01

    The physiological and regulatory effects of overproduction of five cold shock proteins (CSPs) of Lactococcus lactis were studied. CspB, CspD, and CspE could be overproduced at high levels (up to 19% of the total protein), whereas for CspA and CspC limited overproduction (0.3 to 0.5% of the total pro

  14. STRESS-RESPONSE IN LACTOCOCCUS-LACTIS - CLONING, EXPRESSION ANALYSIS, AND MUTATION OF THE LACTOCOCCAL SUPEROXIDE-DISMUTASE GENE

    NARCIS (Netherlands)

    SANDERS, JW; LEENHOUTS, KJ; HAANDRIKMAN, AJ; VENEMA, G; KOK, J

    1995-01-01

    In an analysis of the stress response of Lactococcus lactis, three proteins that were induced under low pH culture conditions were detected. One of these was identified as the lactococcal superoxide dismutase (SodA) by N-terminal amino acid sequence analysis. The gene encoding this protein, designat

  15. Expression of the pyrG gene determines the pool sizes of CTP and dCTP in Lactococcus lactis

    DEFF Research Database (Denmark)

    Jørgensen, C.M.; Hammer, Karin; Jensen, Peter Ruhdal;

    2004-01-01

    The pyrG gene from Lactococcus lactis encodes CTP synthase (EC 6.4.3.2), an enzyme converting UTP to CTP. A series of strains were constructed with different levels of pyrG expression by insertion of synthetic constitutive promoters with different strengths in front of pyrG. These strains expressed...

  16. Reconstitution of the Leucine Transport System of Lactococcus lactis into Liposomes Composed of Membrane-Spanning Lipids from Sulfolobus acidocaldarius

    NARCIS (Netherlands)

    in t Veld, Geertruida; Elferink, Maria; Driessen, Arnold J.M.; Konings, Wilhelmus

    1992-01-01

    The effect of bipolar tetraether lipids, extracted from the thermophilic archaebacterium Sulfolobus acidocaldarius, on the branched-chain amino acid transport system of the mesophilic bacterium Lactococcus lactis was investigated. Liposomes were prepared from mixtures of monolayer lipids and the bil

  17. Heterologous Gene Expression in Lactococcus lactis subsp. lactis : Synthesis, Secretion, and Processing of the Bacillus subtilis Neutral Protease

    NARCIS (Netherlands)

    Guchte, Maarten van de; Kodde, Jan; Vossen, Jos M.B.M. van der; Kok, Jan; Venema, Gerard

    1990-01-01

    The Bacillus subtilis nprE gene lacking its own promoter sequence was inserted in the lactococcal expression vector pMG36e. Upon introduction of the recombinant plasmid into Lactococcus lactis subsp. lactis strain MG1363, neutral protease activity could be visualized by the appearance of large clear

  18. Recombinant invasive Lactococcus lactis can transfer DNA vaccines either directly to dendritic cells or across an epithelial cell monolayer

    NARCIS (Netherlands)

    Azevedo, de Marcela; Meijerink, Marjolein; Taverne, Nico; Pereira, Vanessa Bastos; LeBlanc, Jean Guy; Azevedo, Vasco; Miyoshi, Anderson; Langella, Philippe; Wells, J.M.; Chatel, Jean Marc

    2015-01-01

    Lactococcus lactis (L. lactis), a generally regarded as safe (GRAS) bacterium has recently been investigated as a mucosal delivery vehicle for DNA vaccines. Because of its GRAS status, L. lactis represents an attractive alternative to attenuated pathogens. Previous studies showed that eukaryotic

  19. Controlled Gene Expression Systems for Lactic Acid Bacteria : Transferable Nisin-Inducible Expression Cassettes for Lactococcus, Leuconostoc, and Lactobacillus spp.

    NARCIS (Netherlands)

    Kleerebezem, Michiel; Beerthuyzen, Marke M.; Vaughan, Elaine E.; Vos, Willem M. de; Kuipers, Oscar P.

    1997-01-01

    A transferable dual-plasmid inducible gene expression system for use in lactic acid bacteria that is based on the autoregulatory properties of the antimicrobial peptide nisin produced by Lactococcus lactis was developed. Introduction of the two plasmids allowed nisin-inducible gene expression in Lac

  20. Versatile vector suite for the extracytoplasmic production and purification of heterologous His-tagged proteins in Lactococcus lactis

    NARCIS (Netherlands)

    Neef, Jolanda; Milder, Fin J.; Koedijk, Danny G. A. M.; Klaassens, Marindy; Heezius, Erik C.; van Strijp, Jos A. G.; Otto, Andreas; Becher, Doerte; van Dijl, Jan Maarten; Buist, Girbe

    2015-01-01

    Recent studies have shown that the Gram-positive bacterium Lactococcus lactis can be exploited for the expression of heterologous proteins; however, a versatile set of vectors suitable for inducible extracellular protein production and subsequent purification of the expressed proteins by immobilized

  1. Functional analysis of glycosyltransferase genes from Lactococcus lactis and other gram-positive cocci: complementation,expression, and diversity

    NARCIS (Netherlands)

    Kranenburg, van R.; Vos, H.R.; Swam, van I.I.; Kleerebezem, M.; Vos, de W.M.

    1999-01-01

    Sixteen exopolysaccharide (EPS)-producing Lactococcus lactis strains were analyzed for the chemical compositions of their EPSS and the locations, sequences, and organization of the eps genes involved in EPS biosynthesis. This allowed the grouping of these strains into three major groups, representat

  2. The anaerobic (Class III) ribonucleotide reductase from Lactococcus lactis : Catalytic properties and allosteric regulation of the pure enzyme system

    NARCIS (Netherlands)

    Torrents, Eduard; Buist, Girbe; Liu, Aimin; Eliasson, Rolf; Kok, Jan; Gibert, Isidre; Gräslund, Astrid; Reichard, Peter

    2000-01-01

    Lactococcus lactis contains an operon with the genes (nrdD and nrdG) for a class III ribonucleotide reductase, Strict anaerobic growth depends on the activity of these genes. Both were sequenced, cloned, and overproduced in Escherichia coli, The corresponding proteins, NrdD and NrdG, were purified c

  3. Lytic Infection of Lactococcus lactis by Bacteriophages Tuc2009 and c2 Triggers Alternative Transcriptional Host Responses

    NARCIS (Netherlands)

    Ainsworth, S.; Zomer, A.L.; Mahony, J.; Sinderen, D. van

    2013-01-01

    Here we present an entire temporal transcriptional profile of Lactococcus lactis subsp. cremoris UC509.9 undergoing lytic infection with two distinct bacteriophages, Tuc2009 and c2. Furthermore, corresponding high-resolution whole-phage genome tiling arrays of both bacteriophages were performed thro

  4. Ability of Lactococcus lactis to export viral capsid antigens: a crucial step for development of live vaccines

    NARCIS (Netherlands)

    Dieye, Y.; Hoekman, A.J.W.; Clier, F.; Juillard, V.; Boot, H.J.; Piard, J.C.

    2003-01-01

    Thefood grade bacterium Lactococcus lactis is a potential vehicle for protein delivery in the gastrointestinal tract. As a model, we constructed lactococcal strains producing antigens of infectious bursal disease virus (IBDV). IBDV infects chickens and causes depletion of B-lymphoid cells in the bur

  5. Suitability of Lactococcus lactis subsp lactis ATCC 11454 as a protective culture for lightly preserved fish products

    DEFF Research Database (Denmark)

    Wessels, Stephen Wallace; Huss, Hans Henrik

    1996-01-01

    This study is part of strategy to control the human pathogen Listeria monocytogenes in lightly preserved fish products by using food-grade lactic acid bacteria. When the nisin-producing Lactococcus lactis subsp lactis ATCC 11454 was cultured in the same vessel as L-monocytogenes Scott A in brain...

  6. Metabolic Engineering of Mannitol Production in Lactococcus lactis: Influence of Overexpression of Mannitol 1-Phosphate Dehydrogenase in Different Genetic Backgrounds

    NARCIS (Netherlands)

    Wisselink, H.W.; Mars, A.E.; Meer, van der P.; Eggink, G.; Hugenholtz, J.

    2004-01-01

    To obtain a mannitol-producing Lactococcus lactis strain, the mannitol 1-phosphate dehydrogenase gene (mtlD) from Lactobacillus plantarum was overexpressed in a wild-type strain, a lactate dehydrogenase(LDH)-deficient strain, and a strain with reduced phosphofructokinase activity. High-performance l

  7. A POSSIBLE CONTRIBUTION OF MESSENGER-RNA SECONDARY STRUCTURE TO TRANSLATION INITIATION EFFICIENCY IN LACTOCOCCUS-LACTIS

    NARCIS (Netherlands)

    VANDEGUCHTE, M; VANDERLENDE, T; KOK, J; VENEMA, G

    1991-01-01

    Gene expression signals derived from Lactococcus lactis were linked to lacZ-fused genes with different 5'-nucleotide sequences. Computer predictions of mRNA secondary structure were combined with lacZ expression studies to direct base-substitutions that could possibly influence gene expression. Muta

  8. Fermentation-induced variation in heat and oxidative stress phenotypes of Lactococcus lactis MG1363 reveals transcriptome signatures for robustness

    NARCIS (Netherlands)

    A.R. Dijkstra; W. Alkema; M.J.C. Starrenburg; J. Hugenholtz; S.A.F.T. van Hijum; P.A. Bron

    2014-01-01

    Background: Lactococcus lactis is industrially employed to manufacture various fermented dairy products. The most cost-effective method for the preservation of L. lactis starter cultures is spray drying, but during this process cultures encounter heat and oxidative stress, typically resulting in low

  9. Twofold reduction of phosphofructokinase activity in Lactococcus lactis results in strong decreases in growth rate and in glycolytic flux

    DEFF Research Database (Denmark)

    Andersen, Heidi Winterberg; Solem, Christian; Hammer, Karin;

    2001-01-01

    Two mutant strains of Lactococcus lactis in which the promoter of the las operon, harboring pfk, pyk, and ldh, were replaced by synthetic promoters were constructed. These las mutants had an approximately twofold decrease in the activity of phosphofructokinase, whereas the activities of pyruvate...

  10. The riboflavin transporter RibU in Lactococcus lactis : Molecular characterization of gene expression and the transport mechanism

    NARCIS (Netherlands)

    Burgess, CM; Slotboom, DJ; Geertsma, ER; Duurkens, Hinderika; Poolman, B; van Sinderen, D

    2006-01-01

    This study describes the characterization of the riboflavin transport protein RibU in the lactic acid bacterium Lactococcus lactis subsp. cremoris NZ9000. RibU is predicted to contain five membrane-spanning segments and is a member of a novel transport protein family, not described in the Transport

  11. Antimicrobial Activities of Five Strains Of Lactococcus Isolated from Beef Against Indicator Organisms of Public Health Significance

    Directory of Open Access Journals (Sweden)

    Olusegun Ayodele Olaoye

    2016-10-01

    Full Text Available Five strains of Lactococcus, including L. garviae K2, L. piscium SU4, L. lactis subsp. cremoris E22, L. plantarum L7 and L. lactis subsp. hordinae E91 were screened for production of antimicrobial agents. The strains were also analysed for antimicrobial activities against spoilage and pathogenic organisms, including Staphylococcus aureus, Salmonella Typhimurium, Escherichia coli, Yersinia enterocolitica, Pseudomonas aeruginosa, Klebsiella pneumoniae, Listeria monocytogenes, Bacillus cereus and Pseudomonas fluorescens. Result revealed that L. piscium SU4, L. plantarum L7 and L. lactis subsp. cremoris E22 had lactic acid production (g/107 colony forming units, CFU of 7.23, 7.20 and 7.19. The value of 6.83 recorded as lactic acid produced by L. garviae K2 was significantly different from those obtained for others. The highest acetic acid production (3.55 g/107 CFU was recorded for L. garviae K2 while L. piscium SU4 had the lowest (2.99 g/107 CFU. L. lactis subsp. hordinae E91 had diacetyl production of 71.99 (µg/107 CFU, which was higher than those recorded for other Lactococcus strains. Test for antimicrobial activities showed that Escherichia coli NCTC 86, Yersinia enterocolitica NCTC 10460, Pseudomonas aeruginosa NCIMB 10848, Bacillus cereus NCTC 21113 and Pseudomonas flourescens recorded higher susceptibilities to the antimicrobial action of the Lactococcus strains than others; zones of inhibition of 5 mm and above were recorded for the indicator organisms compared to lower values (<5 mm obtained for others. Listeria monocytogenes also showed medium susceptibility (zones of inhibition <5 mm to the antimicrobial activities of the Lactococcus strains. It was concluded that the Lactococcus strains could be effective in the control of spoilage and pathogenic organisms; their antagonism recorded against Listeria monocytogenes, E. coli, Salmonella Typhimurium and Staphylococcus aureus may be of public health significance.

  12. Genética y genómica enfocadas en el estudio de la resistencia bacteriana Genetics and Genomics for the study of bacterial resistance

    Directory of Open Access Journals (Sweden)

    Ulises Garza-Ramos

    2009-01-01

    Full Text Available La resistencia bacteriana es un problema de salud pública causante de índices elevados de morbi-mortalidad hospitalaria. En la medida en que se usan los diferentes antibióticos se seleccionan bacterias resistentes a múltiples fármacos. El desarrollo de nuevas herramientas moleculares de la genómica y proteómica, como el PCR en tiempo real, pirosecuenciación de ADN, espectrometría de masas, microarreglos de ADN y bioinformática, permite conocer en forma más estrecha la fisiología y estructura de las bacterias y los mecanismos de resistencia a los antibióticos. Estos estudios hacen posible identificar nuevos blancos farmacológicos y diseñar antibióticos específicos para suministrar tratamientos más certeros que combatan las infecciones producidas por bacterias. Con estas técnicas también es posible la identificación rápida de los genes que confieren la resistencia a los antibióticos y el reconocimiento de las estructuras genéticas complejas como los integrones, que intervienen en la diseminación de los genes que producen la multirresistencia.Bacterial resistance is a public health problem causing high rates of morbidity and mortality in hospital settings. To the extent that different antibiotics are used, bacteria resistant to multiple drugs are selected. The development of new molecular genomic and proteomic tools such as real-time PCR, DNA pyrosequencing, mass spectrometry, DNA microarrays, and bioinformatics allow for more in-depth knowledge about the physiology and structure of bacteria and mechanisms involved in antibiotic resistance. These studies identify new targets for drugs and design specific antibiotics to provide more accurate treatments to combat infections caused by bacteria. Using these techniques, it will also be possible to rapidly identify genes that confer resistance to antibiotics, and to identify complex genetic structures, such as integrons that are involved in the spread of genes that confer

  13. Endocardite bacteriana como complicação de sepse neonatal - relato de caso Bacterial endocarditis as a complication of neonatal sepsis: a case report

    Directory of Open Access Journals (Sweden)

    V.L.J. Krebs

    1999-12-01

    Full Text Available Os autores relatam um paciente com 11 dias de vida, internado em Unidade de Terapia Intensiva Neonatal devido a múltiplas malformações congênitas, apresentando sepse e endocardite bacteriana. Entre os fatores de risco para endocardite foram destacados o cateterismo venoso central, hemocultura com crescimento de Staphylococcus aureus e ventilação mecânica. O diagnóstico foi realizado no 61o dia de internação devido a presença de febre persistente e aparecimento de sopro cardíaco sistólico. O ecocardiograma mostrou trombo em átrio direito, medindo 1,9 x 0,7mm sendo realizada antibioticoterapia e ressecção cirúrgica, com melhora clínica. No 125° dia de internação ocorreu óbito devido à sepse e abscesso cerebral. Na necrópsia não foram observados malformações cardíacas. Os autores concluem ser de grande importância o conhecimento das complicações potenciais das técnicas invasivas utilizadas em recém-nascidos criticamente doentes. A suspeita clínica de endocardite deve ser realizada em todos os neonatos com sepse, internados em Unidade de Terapia Intensiva Neonatal por tempo prolongadoThe authors reported on a 11 day-old child, admitted in Neonatal Intensive Care Unit for multiple congenital malformations, who had sepsis and bacterial endocarditis. Among the risk factors for endocarditis were outstanding: the central venous catheterism, hemoculture with growth of Staphylococcus aureus and mechanical ventilation. The diagnosis was made in the 61st day after admission owing to the presence of persistent fever and appearance of systolic murmur. The echocardiogram revealed a thrombus in the right atrium measuring 1.9 x 0.7mm. Antibiotic therapy and surgical resection being performed, with clinical improvement. On the 125st day after admission the patient died owing sepsis and cerebral abscess. At necropsy, heart malformations were not observed. The authors concluded to be very important the knowledge of the potential

  14. Meningencefalites bacterianas agudas em crianças: complicações e sequelas neurológicas Acute bacterial meningoencephalitis in children: complications and neurologic sequelae

    Directory of Open Access Journals (Sweden)

    WLADIMIR NATALINO

    1999-06-01

    Full Text Available Foram estudadas 271 crianças com idade inferior a 15 anos, com diagnóstico de meningencefalite bacteriana aguda (MBA, no período 1980 -- 1990. Os pacientes foram divididos em dois grupos, conforme não tivessem recebido tratamento prévio (STP, 153 casos, e os que receberam tratamento prévio (CTP, 118 casos. Ocorreram diferenças significativas em relação a identificação do agente etiológico, que foi maior no grupo STP, e em relação a ocorrência de ventriculite, maior no grupo CTP. Ocorreu óbito em 19,5% dos 271 casos, com predomínio em crianças de idade abaixo de 12 meses (29,7% e nos pacientes com MBA por Streptococcus pneumoniae. As manifestações epilépticas e as paresias na fase aguda da MBA predominaram em crianças de idade abaixo de 1 ano. Foram identificados e tratados do ponto de vista neurocirúrgico as ventriculites, higroma subdural, hidrocefalia, empiema subdural e abscesso cerebral.We studied 271 children under age of 15 with diagnosis of acute bacterial meningencephalitis treated at Medical School in Ribeirão Preto, University of São Paulo, between 1980 and 1990. The patients were divided in two groups: 1 those who had not received previous antibiotics treatment (NTP, with 153 cases; and 2, those who had received previous antibiotics treatment (PT, with 118 cases. The etiological agent was more frequently identified in NPT group, while ventriculitis was more frequent in PT group. Mortality rate accounted for 19,5% of all cases, and 29.7% of children under 12 months of age. Acute meningitis caused by Streptococcus pneumoniae was frequently followed by increased mortality. Convulsive disorders and hemiparesis predominante among children under 12 months of age. On the neurosurgical point of view, ventriculitis, subdural hygroma, hydrocephalus, subdural empyema and brain abscess were identified and treated

  15. Estudo dos efeitos da solução salina hipertônica e do Ringer lactato sobre a resposta da microcirculação mesentérica e a translocação bacteriana em modelo de obstrução intestinal e isquemia em ratos

    OpenAIRE

    Fernando Luiz Zanoni

    2010-01-01

    INTRODUÇÃO: Estudos demonstram que a solução salina hipertônica melhora a hemodinâmica, a microcirculação e modula o sistema imune, atenuando a resposta inflamatória associada ao choque e trauma. Este estudo tem por objetivo avaliar e comparar os efeitos da solução salina hipertônica (NaCl, 7,5%) e do Ringer lactato seguido da ressecção de segmento do intestino necrosado no tratamento da obstrução intestinal e isquemia, através da análise da translocação bacteriana, da disfunção microcirculat...

  16. Infecção bacteriana em pacientes portadores de Leishmaniase visceral Bacterial infection in patients with visceral leishmaniasis

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    Jaqueline Guerreiro

    1985-12-01

    Full Text Available Uma análise retrospectiva de 63 casos de Leishmaniose visceral (L.V. revelou a presença, em 33 deles, de infecção bacteriana associada. Infecções do trato respiratório foram observadas em 13 (39,3% pacientes, comprometimento de pele em 4 (12%, do trato urinário em 4 (12%, do ouvido em 3 (9%, e de orofaringe em 2 (6%. Sete (21% pacientes apresentaram infecção concomitante em múltiplos sítios. Documentação bacteriológica através de isolamneto do agente etiológico foi obtida em 10, não havendo predominância estatisticamente significante de bactérias Gram positivas ou negativas. Houve 9 casos de óbito nestes 63 pacientes, sendo que em 8 deles a infecção bacteriana fazia parte do quadro clínico final. A análise das taxas de globulinas séricas revelou que infecção esteve presente de modo significativo (p 0.05 com relação ao número de neutrófilos entre os grupos com e sem infecção bacteriana. Concluiu-se, portanto, que infecção bacteriana é um achado freqüente em pacientes com L.V. e se constitui num sinal de mau prognóstico da doença.In an analysis of 63 hospitalized cases with visceral leishmaniasis, the clinical or post-mortem diagnosis of bacterial infection was performed in 33; 13 (39.3% patients had respiratory infection, 4 (12.1% had skin infection, 4 had urinary tract infection, 3 (9.0% showed ear infection and 2 (6.6% had infection of the oral cavity. It is worth mentioning that in 7 (21% cases there was infection in multiple sites. Gram positive and/or Gram negative organisms were isolated from 10 patients. In only two (autopsied cases, infection with less common organisms was recorded, one with disseminated candidiasis and another with disseminated tuberculosis. Death occurred in 9 of the 63 cases, and in 8 of these, concomitant bacterial infection of importance was documented. Patients who had serum globulins lower than 4 g% had significantly more infection (p less than 0.05 than patients with

  17. Cuerpos de inclusión, células bacterianas y composiciones que los contienen y sus usos

    OpenAIRE

    Veciana Miró, Jaume; Ratera Bastardas, Inmaculada; Díez Gil, César; Villaverde Corrales, Antonio Pedro; Vázquez Gómez, Esther; García Fruitós, Elena

    2008-01-01

    [ES] La presente invención se refiere a un cuerpo de inclusión aislado que comprende un polipéptido caracterizado porque el cuerpo de inclusión está en forma particulada. La presente invención también se refiere a una célula bacteriana que comprende dicho cuerpo de inclusión. La presente invención se refiere además a una composición que comprende dicho cuerpo de inclusión y una célula eucariota. La presente invención se refiere también a una composición que comprende dicho cuerpo de ...

  18. Bacterial translocation in rats nonfunctioning diverted distal colon Translocação bacteriana no coto colônico distal desfuncionalizado de ratos

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    Francisco Edilson Leite Pinto Júnior

    2007-06-01

    colite de derivação fecal, seriam capazes de permitir Translocação Bacteriana (TB, ou se a mucosa intestinal atrofiada permitiria a passagem de bactérias para órgãos à distância. MÉTODOS: Foram utilizados 62 ratos Wistar, machos, pesando entre 220 e 320 gramas, divididos em dois grupos: A (Colostomia e B (Controle, contendo cada um 31 animais. No grupo A, os animais foram submetidos à colostomia, terminal boca única, em cólon ascendente. A partir do 70º dia de observação os seguintes procedimentos foram adotados: em cinco ratos foi injetado por via retal no segmento desfuncionalizado - 2ml de uma solução salina 0,9% nos animais (subgrupo A1; em oito inoculou-se, por via retal, uma solução de 2ml contendo Escherichia coli ATCC 25922 (American Type Culture Collection, na concentração de 10(8 Unidades Formadoras de Colônias por mililitros (UFC/ml - Subgrupo A2; em dez animais inoculava-se a mesma solução de E. coli, na concentração de 10(11UFC/ml (Subgrupo A3; e em oito colhia-se o muco do segmento colônico distal desfuncionalizado, para dosagens de açúcares neutros e proteínas totais (subgrupo A4. Os animais do grupo B foram submetidos aos mesmos procedimentos do grupo A, e não foram submetidos à colostomia. Nos animais dos subgrupos A1, A2, A3, B1, B2, e B3, após serem mortos, realizou-se punção cardíaca para coleta de 2ml de sangue e retiraram-se fragmentos de tecidos de linfonodo do mesocólon, fígado, baço, pulmão e rim, para análise microbiológica. Essa análise consistia em evidenciar a presença de UFC de Escherichia coli ATCC 25922. Os testes de Mann-Whitney e Anova foram aplicados como técnicas investigativas para associação das variáveis. RESULTADOS: A ocorrência de TB, só foi evidenciada nos animais em que a concentração inoculada de Escherichia coli ATCC 25922, atingia níveis de 10(11UFC/ml, ou seja, nos Subgrupos A3 e B3, no entanto, sendo significantemente superior (80% nos animais sem colostomia (subgrupo B3

  19. Bacterial translocation in an experimental intestinal obstruction model: C-reactive protein reliability? Translocação bacteriana no modelo experimental de obstrução intestinal: A proteína C-reativa é confiável?

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    Saleh Ibrahim El-Awady

    2009-04-01

    Full Text Available BACKGROUND: Bacterial translocation occurs in preseptic conditions such as intestinal obstruction through unclear mechanism. The C-reactive protein is an acute phase reactant and a marker of ischemia. METHODS: 45 albino male rats were divided into 3 groups each 15 rats. GI control, GII simple intestinal-obstruction and GIII strangulated obstruction. Outcome measures were: (1 Bacteriologic count and typing for intestinal contents, intestinal wall, liver, mesenteric lymph nodes and blood (cardiac and portal (2 Histopathologic: mucosal injury score, inflammatory cell infiltrate in the wall, MLN, liver, (3 Biochemical: serum CRP, IL-10, mucosal stress pattern (glutathione peroxidase-malonyldialdhyde tissue levels. RESULTS: (1 Intestinal obstruction associates with BT precursors (Bact-overgrowth, mucosal-acidosis, immuno-incomptence, (2 Bacterial translocation (frequency and density was found higher in strangulated I.O, that was mainly enteric (aerobic and anaerobic and mostly E.coli, (3 The pathogen commonality supports the gut origin hypothesis but the systemic inflammatory response goes with the cytokine generating one. (4 The CRP median values for GI, II, III were 0.5, 6.9, 8.5 mg/L, for BT +ve 8 mg/L and 0.75 mg/L for BT -ve rats. CONCLUSION: Bacterial translocation occurs bi-directional (systemic-portal in intestinal obstruction and the resultant inflammatory response pathogenesis is mostly 3 hit model. The CRP is a non selective marker of suspected I.O cases. However, it is a reliable marker of BT, BT density and vascular compromise during I.O.OBJETIVO: Translocação bacteriana ocorre em condições pré-sépticas como na obstrução intestinal por mecanismo não esclarecido. A proteína C-reativa é um marcador de ischemia em fase aguda. A proposição é investigar os possíveis efeitos da obstrução intestinal no equilíbrio ecológico microbiano. MÉTODOS: 45 ratos machos albinos foram distribuídos em três grupos de 15 ratos. GI

  20. Efeito de produtos químicos e biológicos sobre a mancha bacteriana, flora microbiana no filoplano e produtividade de pimentão Effects of chemical and biological products on bacterial spot, microbial flora and yield in bell pepper

    Directory of Open Access Journals (Sweden)

    Débora AG da Silva

    2006-06-01

    Full Text Available Avaliou-se o efeito de pulverizações semanais com sulfato de estreptomicina + oxitetraciclina (0,8 g ia L-1, oxicloreto de cobre (2,4 g ia L-1, biofertilizante Agrobio (5%, e testemunha (água sobre o controle da mancha-bacteriana, sobre a flora microbiana no filoplano e sobre a produtividade de três cultivares de pimentão (Magda, Cascadura Itaipu e Magali R. Os experimentos foram realizados em campo de maio a outubro de 2002. Adotou-se o delineamento de blocos ao acaso, em esquema fatorial (4x3, com quatro repetições. Realizaram-se avaliações semanais, durante três meses para altura de plantas (cm; número de hastes; número total de folhas; número de folhas caídas; incidência de folhas lesionadas; severidade da mancha bacteriana e produtividade (t ha-1. Paralelamente, quantificou-se a população microbiana residente no filoplano e nos frutos. Não houve efeito dos tratamentos sobre a produção de frutos, porém, observou-se efeito sobre o desenvolvimento vegetativo das plantas, sobre a mancha bacteriana e sobre a flora microbiana no filoplano. O oxicloreto de cobre inibiu o desenvolvimento vegetativo, a taxa de abscisão foliar e a flora bacteriana no filoplano. O Agrobio favoreceu o desenvolvimento vegetativo e, assim como o sulfato de estreptomicina + oxitetraciclina, reduziu a população de bactérias, exceto de Bacillus sp., e de fungos, exceto Cladosporium sp., no filoplano. O híbrido Magali R foi significativamente superior às demais cultivares quanto ao vigor das plantas, produtividade e resistência à mancha bacteriana. Estes resultados sugerem atividade bactericida do Agrobio em condições de campo.The effect of weekly sprayings with streptomycin sulfate + oxytetracycline (0.8 g ia L-1, copper oxychloride (2.4 g ia L-1 and Agrobio fertilizer (5% plus a control (water was evaluated in the control of bacterial spot, the microbial flora in the phyloplan, and over yield in three bell pepper cultivars (Magda, Cascadura

  1. Análisis microbiológico y caracterización de poblaciones bacterianas en sistemas de engorde de camarón durante un ciclo de cultivo

    OpenAIRE

    Cedeño, Ricardo

    2005-01-01

    Análisis microbiológico y caracterización de poblaciones bacterianas en sistemas de engorde de camarón durante un ciclo de cultivo En la literatura científica existen varios trabajos de caracterización de la microbiota bacteriana en sistemas de cultivo de Penaeidos, pero muy poca información con respecto a la especie Litopenaeus vannamei en sistemas de engorde locales.

  2. The effect of lactose, NaCl and an aero/anaerobic environment on the tyrosine decarboxylase activity of Lactococcus lactis subsp. cremoris and Lactococcus lactis subsp. lactis.

    Science.gov (United States)

    Buňková, Leona; Buňka, František; Pollaková, Eva; Podešvová, Tereza; Dráb, Vladimír

    2011-05-27

    The aim of this work was to study, under model conditions, combined effects of the concentration of lactose (0-1% w/v), NaCl (0-2% w/v) and aero/anaerobiosis on the growth and tyramine production in 3 strains of Lactococcus lactis subsp. lactis and 2 strains of L. lactis subsp. cremoris. The levels of the factors tested were chosen with respect to the conditions which can occur during the real process of natural cheese production, including the culture temperature (10 ± 1°C). In all strains tested, tyrosine decarboxylation was most influenced by NaCl concentration; the highest production of tyramine was obtained within the culture with the highest (2% w/v) salt concentration applied. Two of the strains L. lactis subsp. lactis produced tyramine only in broth with the highest NaCl concentration tested. In the remaining 3 strains of L. lactis, tyramine was detected under all conditions applied. The tested concentration of lactose and aero/anaerobiosis had a less significant effect on tyramine decarboxylation. However, it was also found that at the same concentrations of NaCl and lactose, a higher amount of tyramine was detected under anaerobic conditions. In all strains tested, tyramine decarboxylation started during the active growth phase of the cells.

  3. Degradación bacteriana de cianuro y compuestos nitrogenados tóxicos

    OpenAIRE

    2016-01-01

    La ruta de asimilación de cianuro en P. pseudoalcaligenes CECT5344 transcurre a través de un nitrilo formado por la reacción química del cianuro con el oxalacetato, siendo este último acumulado como consecuencia de la acción conjunta de una malato:quinona oxidoreductasa (MQO) y la oxidasa terminal resistente a cianuro (CioAB) (Luque-Almagro et al., 2011b). Los nitrilos pueden ser convertidos en amonio por la acción de una nitrilasa o un sistema nitrilo hidratasa/amidasa. ...

  4. Contaminação bacteriana em concentrados plaquetários: identificação, perfil de sensibilidade aos antimicrobianos e sepse associada à transfusão Bacterial contamination on platelet concentrates: identification, antimicrobial susceptibility profile and transfusion-related sepsis

    Directory of Open Access Journals (Sweden)

    Rosiéli Martini

    2010-12-01

    Full Text Available INTRODUÇÃO: Devido à sepse bacteriana associada à transfusão de concentrados plaquetários (CPs ter sérias consequências clínicas para os pacientes, alguns procedimentos têm sido incorporados na preparação e no controle de qualidade dos componentes sanguíneos para reduzir o risco da contaminação bacteriana. Este artigo descreve a prevalência da contaminação bacteriana dos CPs que foram transfundidos, o espectro bacteriano detectado com seu perfil de sensibilidade aos antimicrobianos e as reações transfusionais nos receptores. MÉTODOS: Um total de 292 CPs (278 randômicos e 14 por aférese, proveniente do Hemocentro do Estado do Rio Grande do Sul (HEMORGS de Santa Maria foi testado. As quantidades de 100μL e 200μL foram coletadas da porção tubular da bolsa de plaquetas e semeadas utilizando dois tipos de metodologias. RESULTADOS: Em cinco unidades(1,7%; 5/292 foram isoladas bactérias pela metodologia qualitativa e apenas uma pela quantitativa. Staphylococcus epidermidis foi o microrganismo identificado em todas as amostras. Dois pacientes apresentaram sepse associada à transfusão com desfecho fatal. CONCLUSÕES: A contaminação bacteriana pelas transfusões de CPs constitui-se num importante problema de saúde pública devido a sua associação com altas taxas de morbidade e mortalidade. Neste estudo, somente microrganismos gram-positivos foram isolados sendo que nenhuma amostra obtida por aférese apresentou contaminação.INTRODUCTION: Bacterial sepsis associated with the transfusion of platelet concentrates (PCs results in serious clinical implications for patients. Given these implications, certain procedures have been integrated into the preparation and quality control of blood components to reduce the risk of bacterial contamination. This article describes the prevalence of bacterial contamination on transfused PCs, the bacterial spectrum detected and their antimicrobial susceptibility profile and transfusion

  5. Control analysis as a tool to understand the formation of the las operon in Lactococcus lactis

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Solem, Christian; Jensen, Peter Ruhdal

    2005-01-01

    In Lactococcus lactis the enzymes phosphofructokinase (PFK), pyruvate kinase (PK) and lactate dehydrogenase (LDH) are uniquely encoded in the las operon and we here apply Metabolic Control Analysis to study the role of this organisation. Earlier work showed that LDH at wildtype level has zero...... control on glycolysis and growth rate but high negative control on formate production. We find that PFK and PK have zero control on glycolysis and growth rate at the wildtype enzyme level but both enzymes exert strong positive control on the glycolytic flux at reduced activities. PK has high positive...... control on formate and acetate production, whereas PFK has no control on these fluxes. Decreased expression of the entire las operon resulted in a strong decrease in growth rate and the glycolytic flux; at 53% expression of the las operon the glycolytic flux was reduced to 44% and the flux control...

  6. Analysis of heat shock gene expression in Lactococcus lactis MG1363

    DEFF Research Database (Denmark)

    Arnau, José; Sørensen, Kim; Appel, Karen Fuglede

    1996-01-01

    The induction of the heat shock response in Lactococcus lactis subsp. cremoris strain MG1363 was analysed at the RNA level using a novel RNA isolation procedure to prevent degradation. Cloning of the dnaJ and groEL homologous was carried out. Nothern blot analysis showed a similar induction pattern......, although maximum induction was observed earlier for orf1 and grpE. Novel transcript sizes were detected in heat-shocked cells. The induction kinetics observed for ftsH suggested a different regulation for this gene. Experimental evidence for a prenounced transcriptional regulation being involved...... in the heat shock response in L. lactis MG1363 is presented. A gene located downstream of the dnaK operon in strain MG1363, named orf4, was shown not to be regulated by heat shock....

  7. Biocidal Inactivation of Lactococcus lactis Bacteriophages: Efficacy and Targets of Commonly Used Sanitizers

    Science.gov (United States)

    Hayes, Stephen; Murphy, James; Mahony, Jennifer; Lugli, Gabriele A.; Ventura, Marco; Noben, Jean-Paul; Franz, Charles M. A. P.; Neve, Horst; Nauta, Arjen; Van Sinderen, Douwe

    2017-01-01

    Lactococcus lactis strains, being intensely used in the dairy industry, are particularly vulnerable to members of the so-called 936 group of phages. Sanitization and disinfection using purpose-made biocidal solutions is a critical step in controlling phage contamination in such dairy processing plants. The susceptibility of 36 936 group phages to biocidal treatments was examined using 14 biocides and commercially available sanitizers. The targets of a number of these biocides were investigated by means of electron microscopic and proteomic analyses. The results from this study highlight significant variations in phage resistance to biocides among 936 phages. Furthermore, rather than possessing resistance to specific biocides or biocide types, biocide-resistant phages tend to possess a broad tolerance to multiple classes of antimicrobial compounds. PMID:28210242

  8. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: characterization of the bacteriocin.

    Science.gov (United States)

    Furtado, Danielle N; Todorov, Svetoslav D; Landgraf, Mariza; Destro, Maria T; Franco, Bernadette D G M

    2014-01-01

    Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality.

  9. The pyrimidine operon pyrRPB-carA from Lactococcus lactis

    DEFF Research Database (Denmark)

    Martinussen, Jan; Schallert, J.; Andersen, Birgit;

    2001-01-01

    The four genes pyrR, pyrP, pyrB, and carA were found to constitute an operon in Lactococcus lactis subsp, lactis MG1363. The functions of the different genes were established by mutational analysis. The first gene in the operon is the pyrimidine regulatory gene, pyrR, which is responsible...... for the regulation of the expression of the pyrimidine biosynthetic genes leading to UMP formation. The second gene encodes a membrane-bound high-affinity uracil permease, required for utilization of exogenous uracil. The last two genes in the operon, pyrB and carA, encode pyrimidine biosynthetic enzymes; aspartate....... The expression of the pyrimidine biosynthetic genes including the pyrRPB-carA operon is subject to control at the transcriptional level, most probably by an attenuator mechanism in which PyrR acts as the regulatory protein....

  10. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: characterization of the bacteriocin

    Directory of Open Access Journals (Sweden)

    Danielle N. Furtado

    2014-12-01

    Full Text Available Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality.

  11. An exoproteome approach to monitor safety of a cheese-isolated Lactococcus lactis

    DEFF Research Database (Denmark)

    Genovese, Federica; Coïsson, Jean Daniel; Majumder, Avishek

    2013-01-01

    The safety of the cheese-isolated and potential starter Lactococcus lactis 11D was explored by means of an extracellular proteomic study. A preliminary analysis showed good caseification/proteolytic behavior of the strain, absence of production of biogenic amines and good survival at acidic p...... isomerase were abundant in the L. lactis 11D exoproteome. These proteins play a role in bacterial aggregation and in bacteria–fungi interactions, therefore their presence may indicate a good competition potential of the strain against other microorganisms in both food and the gastrointestinal habitat....... This is to our knowledge the first extracellular proteomic mapping of L. lactis with relevance for bacterial strain-typing in food safety....

  12. Increased biomass yield of Lactococcus lactis during energetically limited growth and respiratory conditions

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Blank, Lars Mathias; Solem, Christian

    2008-01-01

    Lactococcus lactis is known to be capable of respiration under aerobic conditions in the presence of haemin. In the present study the effect of respiration on ATP production during growth on different sugars was examined. With glucose as the sole carbon source, respiratory conditions in L. lactis...... MG1363 resulted in only a minor increase, 21%, in biomass yield. Since ATP production through substrate-level phosphorylation was essentially identical with and without respiration, the increased biomass yield was a result of energy-saving under respiratory conditions estimated to be 0.4 mol of ATP....../mol of glucose. With maltose as the energy source, the increase in biomass yield amounted to 51% compared with an aerobic culture that lacked haemin. This higher ATP yield was obtained by redirecting pyruvate metabolism from lactate to acetate production, and from savings through respiration. However, even after...

  13. Production of recombinant peanut allergen Ara h 2 using Lactococcus lactis

    DEFF Research Database (Denmark)

    Glenting, J.; Poulsen, Lars K.; Kato, K.;

    2007-01-01

    Background: Natural allergen sources can supply large quantities of authentic allergen mixtures for use as immunotherapeutics. However, such extracts are complex, difficult to define, vary from batch to batch, which may lead to unpredictable efficacy and/ or unacceptable levels of side effects....... The use of recombinant expression systems for allergen production can alleviate some of these issues. Several allergens have been tested in high- level expression systems and in most cases show immunereactivity comparable to their natural counterparts. The gram positive lactic acid bacterium Lactococcus...... of the major allergens in peanut have been described. However, for therapeutic usage more information about the individual allergenic components is needed. In this paper we report recombinant production of the Ara h 2 peanut allergen using L. lactis. Results: A synthetic ara h 2 gene was cloned into an L...

  14. Physiochemical parameters optimization for enhanced nisin production by Lactococcus lactis (MTCC 440

    Directory of Open Access Journals (Sweden)

    Puspadhwaja Mall

    2010-02-01

    Full Text Available The influence of various physiochemical parameters on the growth of Lactococcus lactis sub sp. lactis MTCC 440 was studied at shake flask level for 20 h. Media optimization (MRS broth was studied to achieve enhanced growth of the organism and also nisin production. Bioassay of nisin was done with agar diffusion method using Streptococcus agalactae NCIM 2401 as indicator strain. MRS broth (6%, w/v with 0.15μg/ml of nisin supplemented with 0.5% (v/v skimmed milk was found to be the best for nisin production as well as for growth of L lactis. The production of nisin was strongly influenced by the presence of skimmed milk and nisin in MRS broth. The production of nisin was affected by the physical parameters and maximum nisin production was at 30(0C while the optimal temperature for biomass production was 37(0C.

  15. Farmacos orales para el control quimico de las biopeliculas dentales (placa bacteriana

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    Rodrigo Abello Moreno

    2013-12-01

    Full Text Available La placa dentobacteriana o biopelicula es la responsable de patologias clinicas como la caries dental, gingivitis y enfermedad periodontal, por lo tanto productos con agentes germicidas actuan en la prevencion de la biopelicula dental cuando las medidas de higiene oral no son las mas apropiadas.

  16. Farmacos orales para el control quimico de las biopeliculas dentales (placa bacteriana)

    OpenAIRE

    Rodrigo Abello Moreno

    2013-01-01

    La placa dentobacteriana o biopelicula es la responsable de patologias clinicas como la caries dental, gingivitis y enfermedad periodontal, por lo tanto productos con agentes germicidas actuan en la prevencion de la biopelicula dental cuando las medidas de higiene oral no son las mas apropiadas.

  17. La mancha bacteriana del champiñón y otras setas cultivadas

    OpenAIRE

    2011-01-01

    El cultivo de champiñón y otras setas cultivadas se ve afectado por enfermedades de origen bacteriano que pueden causar pérdidas de producción importantes. Para controlar esta enfermedad es fundamental realizar un manejo adecuado del cultivo evitando el exceso de humedad.

  18. Peritonitis bacteriana espontánea: estudio en pacientes cirróticos descompensados con ascitis Spontaneous bacterial peritonitis in decompensated cirrhotic patients with ascites

    Directory of Open Access Journals (Sweden)

    Fernando Montoya Maya

    1995-02-01

    Full Text Available Se realizó un estudio descriptivo prospectivo entre febrero de 1993 y marzo de 1994. Se estudiaron 25 pacientes cirróticos (3 de ellos en dos ocasiones con ascitis clínica o ecográfica que ingresaron al servicio de Medicina Interna del Hospital Universitario San Vicente de Paúl, Medellín, Colombia, por descompensación de su cuadro clínico. A todos se les practicó paracentesis diagnóstica con estudio de citoquímico, citología y cultivo para bacterias aerobias y anaerobias. La edad promedio de los pacientes fue de 43.9 años (13 a 77 afíos, 13 fueron mujeres (52% y 12 hombres (48%. En 11 episodios (39.3% se encontró ascitis infectada, así: ascitis bacteriana 6 casos (54.6% (monomicrobiana en tres y polimicrobiana en otros tres; peritonitis bacteriana espontánea 3 casos (27.2% (polimicrobiana en dos y monomicrobiana en uno y ascitis neutrofílica dos casos (18.2%. El 72.7% de los casos con ascitis infectada tuvieron fiebre contra un 23.5% de aquéllos sin infección (p < 0.014. Asimismo, el dolor abdominal fue un síntoma bastante frecuente (45.5% de infección. La ascitis infectada se presentó únicamente en individuos categoría C de la clasificación de Child-Pugh, con niveles séricos de albúmina, generalmente menores de 2 g/dl (p < 0.01. Los niveles de albúmina en líquido ascítico menores de 1 g/dl no se asociaron a la infección del mismo. Los gérmenes prevalentes fueron Escherichia coli y estreptococos del grupo viridans, cada uno aislado en 5 ocasiones. Los aislamientos fueron polimicrobianos en 5 de nueve casos (55.5%. La mortalidad por ascitis infectada fue de 27.3% (3/11 casos comparable con la debida a causas diferentes (29.4% en individuos con ascitis sin infección (5/17. Se concluye que la infección del líquido ascítico es una complicación frecuente en los pacientes cirróticos descompensados. La fiebre y el dolor abdominal son los signos clínicos cardinales de la infección. El aislamiento frecuente de E

  19. Microbiota of Minas cheese as influenced by the nisin producer Lactococcus lactis subsp. lactis GLc05.

    Science.gov (United States)

    Perin, Luana Martins; Dal Bello, Barbara; Belviso, Simona; Zeppa, Giuseppe; de Carvalho, Antônio Fernandes; Cocolin, Luca; Nero, Luís Augusto

    2015-12-01

    Minas cheese is a popular dairy product in Brazil that is traditionally produced using raw or pasteurized cow milk. This study proposed an alternative production of Minas cheese using raw goat milk added of a nisin producer Lactococcus lactis subsp. lactis GLc05. An in situ investigation was carried on to evaluate the interactions between the L. lactis subsp. lactis GLc05 and the autochthonous microbiota of a Minas cheese during the ripening; production of biogenic amines (BAs) was assessed as a safety aspect. Minas cheese was produced in two treatments (A, by adding L. lactis subsp. lactis GLc05, and B, without adding this strain), in three independent repetitions (R1, R2, and R3). Culture dependent (direct plating) and independent (rep-PCR and PCR-DGGE) methods were employed to characterize the microbiota and to assess the possible interferences caused by L. lactis subsp. lactis GLc05. BA amounts were measured using HPLC. A significant decrease in coagulase-positive cocci was observed in the cheeses produced by adding L. lactis subsp. lactis GLc05 (cheese A). The rep-PCR and PCR-DGGE highlighted the differences in the microbiota of both cheeses, separating them into two different clusters. Lactococcus sp. was found as the main microorganism in both cheeses, and the microbiota of cheese A presented a higher number of species. High concentrations of tyramine were found in both cheeses and, at specific ripening times, the BA amounts in cheese B were significantly higher than in cheese A (pnisin producer L. lactis subsp. lactis GLc05 was demonstrated in situ, by demonstration of its influence in the complex microbiota naturally present in a raw goat milk cheese and by controlling the growth of coagulase-positive cocci. L. lactis subsp. lactis GLc05 influenced also the production of BA determining that their amounts in the cheeses were maintained at acceptable levels for human consumption.

  20. Nisin inducible production of listeriolysin O in Lactococcus lactis NZ9000

    Directory of Open Access Journals (Sweden)

    Griffin Brendan T

    2008-07-01

    Full Text Available Abstract Background Listeria monocytogenes is a well-characterized food-borne pathogen that infects pregnant women and immunocompromised individuals. Listeriolysin O (LLO is the major virulence factor of the pathogen and is often used as a diagnostic marker for detection of L. monocytogenes. In addition, LLO represents a potent antigen driving T cell-mediated immunity during infection. In the present work, Lactococcus lactis NZ9000 was used as an expression host to hyper-produce LLO under inducible conditions using the NICE (NIsin Controlled Expression system. We created a modified pNZ8048 vector encoding a six-His-tagged LLO downstream of the strong inducible PnisA promoter. Results The constructed vector (pNZPnisA:CYTO-LLO was expressed in L. lactis NZ9000 and was best induced at mid-log phase with 0.2% v/v nisin for 4 h statically at 30°C. Purification of the His-tagged LLO was accomplished by Ni-NTA affinity chromatography and functionality was confirmed through haemolytic assays. Total LLO yield (measured as total protein content was 4.43–5.9 mg per litre culture and the haemolytic activity was still detectable after 8 months of storage at 4°C. Conclusion The LLO production method described in this work provides an approach to efficient LLO production in the Gram-positive Lactococcus bacterium to yield a significant source of the protein for research and diagnostic applications. Expression of LLO in L. lactis has a number of benefits over E. coli which may facilitate both in vivo and in vitro applications of this system.

  1. BRONCHOALVEOLAR LAVAGE FLUID BACTERIAL ISOLATION AND SENSIBILITY IN HEALTH AND SICK DOGS La identificación bacteriana y sensibilidad antimicrobiana de líquido de lavado tracheobronchial de sanos y enfermos perros IDENTIFICAÇÃO BACTERIANA E SENSIBILIDADE ANTIMICROBIANA DO FLUIDO DE LAVAGEM TRAQUEOBRÔNQUICA DE CÃES SADIOS E DOENTES

    Directory of Open Access Journals (Sweden)

    Paula Cristina Basso

    2009-09-01

    ón bacteriana de las muestras y de pruebas de sensibilidad a los antibióticos por el método de difusión en agar. Las bacterias aisladas fueron: Haemophilus aphrophilus, Staphylococcus aureus, S. epidermidis, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosas y Proteus mirabilis. Entre las muestras analizadas, 63% mostraron resistencia a diversos antibióticos. Se concluyó que la resistencia a la acción de los antibióticos está presente tanto en animales sanos como los enfermos, y que la ceftriaxona asociada con amoxicilina clavulánico y son eficaces contra las bacterias en el tracto respiratorio de perros.

    Pesquisas sobre a utilização de antibióticos e a resistência aos antimicrobianos em animais de produção são realizadas em diversos países. No entanto, poucos estudos incluem os agentes bacterianos associados ao trato respiratório de animais de companhia. O objetivo deste trabalho foi verificar o perfil de resistência antimicrobiana no fluido do lavado traqueobrônquico de cães saudáveis e doentes. Utilizaram-se vinte animais, dez clinicamente saudáveis (Grupo 1 e dez com distúrbio respiratório (Grupo 2. A colheita do lavado traqueobrônquico foi realizada com tubo endotraqueal ou guiada com o auxílio de um endoscópio rígido. Efetuaram-se o cultivo e a identificação bacteriana das amostras e teste de sensibilidade a antimicrobianos pelo método de difusão em ágar. As bactérias isoladas foram: Haemophilus aphrophilus, Staphylococcus aureus, S. epidermidis, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosas e Proteus mirabilis. Dentre as amostras analisadas, 63% demonstraram resistência bacteriana a diferentes antimicrobianos. Conclui-se que resistência à ação dos antibióticos está presente tanto nos animais sadios quanto nos doentes e que a ceftriaxona e a amoxicilina associada com ácido clavulânico s

  2. Epidemiological profile of acute bacterial meningitis in the state of Rio Grande do Norte, Brazil Perfil epidemiológico da meningite bacteriana aguda no estado do Rio Grande do Norte, Brasil

    Directory of Open Access Journals (Sweden)

    Wallace Andrino da Silva

    2010-08-01

    Full Text Available INTRODUCTION: Acute bacterial meningitis (ABM remains a public health problem in Brazil. To evaluate the epidemiology of ABM cases at Giselda Trigueiro Hospital, Rio Grande do Norte, a descriptive retrospective survey was conducted covering 2005 to 2008. METHODS: Clinical and laboratory data were collected from the epidemiology department of the hospital and analyzed. RESULTS: Out of 168 ABM cases, 24.4%, 10.7%, and 2.4% were, respectively, caused by Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenza b, and 5.4% by other bacteria. The mean age was 22.48 ± 18.7 years old. CONCLUSIONS: Streptococcus pneumoniae was the main causative pathogen in the young urban population.INTRODUÇÃO: Meningite bacteriana aguda (MBA permanece um problema de saúde pública no Brasil. Para avaliar a epidemiologia da MBA atendida no Hospital Giselda Trigueiro, Rio Grande do Norte, um estudo retrospectivo-descritivo foi realizado de 2005 a 2008. MÉTODOS: Dados clínicos e laboratoriais foram coletados do departamento de epidemiologia hospitalar e analisados. RESULTADOS: Dos 168 casos de MBA, 24,4%, 10,7% e 2,4% foram, respectivamente, causados por Streptococcus pneumoniae, Neisseria meningitidis e Haemophilus influenzae b e 5,4% por outras bactérias. A média da idade foi 22,48 ± 18,7 anos. CONCLUSÕES: Streptococcus pneumoniae foi o principal patógeno causador na população urbana jovem.

  3. La resistencia bacteriana transmitida al hombre a través de los alimentos y el uso responsable de los antimicrobianos como moduladores de crecimiento

    OpenAIRE

    Gimeno, Emilio J.

    2001-01-01

    El objetivo de la presente comunicación es hacer un aporte para esclarecer a la opinión pública sobre la teoría y práctica de la resistencia bacteriana en relación con los moduladores de crecimiento, aportando datos, informes e ideas basadas en aspectos técnicos y hechos prácticos , científicamente demostrados sobre información consolidada.

  4. Optimization of Fermentation Conditions for Nisin Production by Lactococcus lactis N302%Nisin生产菌株Lactococcus lactis N302的发酵优化

    Institute of Scientific and Technical Information of China (English)

    李瑞青; 轩辕铮铮; 姜德洲; 苏俊杰; 徐海津; 张秀明; 乔明强

    2011-01-01

    对一株Nisin生产菌株Lactococcus lactis N302现有培养基进行了氮源替代,并采用Plackett-Burman(PB)法和中心复合设计(Central Composite Design)对影响其发酵生产Nisin的6个培养条件进行筛选优化.PB实验表明,蔗糖、初始pH值和酵母粉是影响Nisin效价的三个关键因素.对三因素进行中心复合设计,经响应面法优化分析(RSM)确定了L.Lactis N302发酵生产Nisin的最优条件为:蔗糖13.7g.L-1,初始pH值7.74,酵母粉25.7g.L-1,大豆蛋白胨10.0g.L-1,K2HPO410.0g.L-1,接种量3%.优化后Nisin效价较优化前提高了7.2%.小试(10 L)研究表明,分批发酵18h、补碱分批发酵16h菌株L.lactis N302单位Nisin效价最高,分别为4 597.03 IU.mL-1和8 773.34 IU.mL-1.%Nisin is a bacteriocin widely used in food industry as an effective food preservative. High nisin production was aimed by optimizing the fermentation conditions of Lactococcus lactis N302. First, soybean peptone was used the main nitrogen source of the culture medium instead of peptone. Then, the Plackett-Burman design (PB) and the path of steepest ascent method were applied to investigate the main factors that affect the yield of nisin, and to find the optimum region of the response. The results indicated that sucrose, initial pH value and yeast extract were the significant factors for nisin production. Central composite experimental design and response surface methodology (RSM) were further adopted to derive a statistical model for optimizing the fermentation conditions. The optimum fermentation conditions were found to be sucrose 13. 7 g · L-1, initial pH value 7. 74, yeast extract 25. 7 g · L-1, soybean peptone 10 g · L-1, K2HPO410 g · L-1, inoculum size 3%. The nisin yield increased by 7. 2% compared to the no-optimized conditions. Finally, 10 liter batch and pH fed-batch fermentation with the optimized conditions were carried out. The maximum nisin yield was achieved at 18 h for batch fermentation and 16 h for fed

  5. Atividade enzimática e perfil da comunidade bacteriana em solo submetido à solarização e biofumigação Enzymatic activity and bacterial community profile in soil under solarization e biofumigation

    Directory of Open Access Journals (Sweden)

    Samuel Ribeiro Passos

    2008-07-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da solarização e da biofumigação sobre a comunidade microbiana do solo, por meio da atividade da enzima beta-glicosidase e do perfil do 16S rDNA, determinado com PCR-DGGE. A solarização do solo, com cobertura de plástico, foi feita por períodos de dois, quatro e seis meses, e a biofumigação foi realizada pela incorporação de 2 e 5% (v/v de cama-de-frango ao solo. Logo após a retirada da cobertura de plástico e aos 30 dias após a remoção, a atividade da beta-glicosidase foi menor em relação ao tratamento não solarizado. Aos 60 dias, não foram mais observadas diferenças entre os tratamentos. A adição de cama-de-frango a 5% estimulou a atividade da beta-glicosidase. O perfil da estrutura da comunidade bacteriana foi influenciado pelo tempo de solarização, independentemente da época da retirada da cobertura de plástico. Não foi observado efeito da adição de cama-de-frango ao solo, no perfil da comunidade. A solarização afeta a atividade da beta-glicosidase, mas esses efeitos não são mais detectáveis após 60 dias da retirada da cobertura de plástico, diferentemente do que foi observado em relação à estrutura da comunidade bacteriana por PCR-DGGE. A biofumigação estimula a atividade da beta-glicosidase, mas não afeta o perfil da comunidade microbiana.The objective of this work was to evaluate the effects of solarization and biofumigation on the soil microbial communities, by means of beta-glucosidase activity and 16S rDNA PCR-DGGE analyses. Solarization with a plastic covering of the soil took place over two, four and six months, and the soils were biofumigated by the addition of 2 and 5% (v/v of chicken litter to the soil. Right after the plastic cover removal and after 30 days, beta-glucosidase was lower than in the nonsolarizated control. After 60 days, there were no longer significant differences in beta-glucosidase activity between treatments. The addition

  6. Bactérias endofíticas no controle e inibição in vitro de Pseudomonas syringae pv tomato, agente da pinta bacteriana do tomateiro Control with endophytic bacteria and in vitro inhibition of Pseudomonas syringae pv tomato, agent of bacterial speck of tomato

    Directory of Open Access Journals (Sweden)

    Juliana Resende Campos Silva

    2008-08-01

    Full Text Available Para avaliar o potencial de 53 isolados de bactérias endofíticas no controle da pinta bacteriana do tomateiro (Lycopersicum esculentum Mill., realizaram-se seleções massais em casa-de-vegetação e a seguir foi avaliado, in vitro, o antagonismo desses isolados sobre a bactéria desafiante Pseudomonas syringae pv. tomato (Pst. A inoculação das bactérias endofíticas foi feita por microbiolização das sementes de tomate cv. Santa Clara e da desafiante (Pst por pulverização. Aos 7, 14 e 21 dias após a inoculação da Pst, foram realizadas as avaliações da severidade da pinta bacteriana, bem como da altura das plantas. As espécies e os isolados bacterianos mais eficazes na redução da severidade da pinta bacteriana foram: Acinetobacter johnsonii (isolado 10, Bacillus pumilus (isolados 3, 12, 20, 39, 51, Paenibacillus macerans (isolados 37 e 47, PIM 11, Bacillus sphaericus (isolado 45, B. amyloliquefaciens (isolado 50, TOM 2, TOM 24 e Staphylococcus aureus (isolado 18. Mais de 50% dos isolados eficazes na redução da severidade foram da espécie Bacillus pumilus. Das espécies endofíticas mais eficazes na redução da severidade da pinta bacteriana, Bacillus pumilus e B. amyloliquefaciens inibiram também o crescimento da Pst in vitro.Vários dos isolados promoveram também o crescimento das plantas.To asses the potential of fifty three isolates of endophytic bacteria on the control of Pseudomonas syringae pv. tomato (Pst in tomato (Lycopersicum esculentum Mill., several screening were done in greenhouse followed by in vitro studies on antagonism of those isolates to Pst. The inoculation of endophytic bacteria was done by microbiolization of tomato cv Santa Clara seeds. The challenging bacterium (Pst inoculation was done by spraying. At 7, 14 and 21 days after Pst inoculation the assessment of bacterial speck severity was done, and height of plants was also measured. The most efficient endophytic species and isolates in reducing

  7. Sensibilidade a cobre, estreptomicina e oxitetraciclina em Xanthomonas spp. associadas à mancha-bacteriana do tomate para processamento industrial

    Directory of Open Access Journals (Sweden)

    Quezado-Duval Alice Maria

    2003-01-01

    Full Text Available Apesar de amplamente empregados em lavouras de tomate para processamento industrial no Brasil, fungicidas cúpricos e antibióticos registrados para uso agrícola nem sempre resultam em controle eficiente das bacterioses que afetam a cultura. O aparecimento de estirpes resistentes é uma das causas dessa baixa eficiência. Avaliou-se, in vitro, a sensibilidade a cobre, estreptomicina e oxitetraciclina de 389 isolados de Xanthomonas spp. associadas à mancha-bacteriana do tomateiro, sendo 92 de X. axonopodis pv. vesicatoria (60 do grupo "A"/raça T1 e 32 do "C"/raça T3, 93 de X. vesicatoria (grupo "B"/raça T2 e 204 de X. gardneri (grupo "D"/raça T2. Os isolados foram obtidos de plantas doentes em campos comerciais de tomate para processamento industrial nos estados de Goiás, Minas Gerais, Pernambuco e Bahia, nos anos de 1995 a 1998 e em 2000. Alíquotas de 5 ml de suspensões bacterianas foram depositadas em meio Nutriente-Ágar suplementado com sulfato de cobre, nas concentrações de 50 e 200 µg/ml; sulfato de estreptomicina, a 25 e 200 µg/ml e cloridrato de oxitetraciclina, a 25 µg/ml. Nenhum isolado foi resistente a oxitetraciclina, como também nenhum foi resistente ao cobre na concentração de 200 µg/ml do sulfato de cobre. No entanto, houve diferença entre isolados quanto à sensibilidade ao sulfato de cobre na concentração de 50 µg/ml e ao sulfato de estreptomicina nas duas concentrações empregadas. As freqüências de isolados de X. gardneri, X. axonopodis pv. vesicatoria (grupos "A" e "C" e X. vesicatoria resistentes à estreptomicina (25 µg/ml do produto usado foram, respectivamente, 98%, 38% e 2%, ao passo que, ao cobre, foram, respectivamente, 48%, 4% e 74%. Todos os isolados do grupo "C" foram sensíveis à estreptomicina e 97% sensíveis ao cobre.

  8. Infección genital por Chlamydia trachomatis y otros microorganismos en dos grupos de mujeres en Cartagena Frequency of genital infection with chlamydia trachomatis and other microorganisms in two groups of women in Cartagena, Colombia

    OpenAIRE

    Alfonso Pulido; Armando Flecha; Ivonne Correa; Gregorio Young; Delfina Urbina

    1992-01-01

    Las enfermedades asociadas a la infección por Chlamydia trachomatis y la vaginosis bacteriana son de importancia en la población sexual mente activa, por lo que amerita estudiarlas. Con la finalidad de conocer su frecuencia en Cartagena se estudiaron, entre 1988 y 1990, 431 mujeres que acudieron a la consulta ginecológica del Hospital Universitario de Cartagena o al Centro Venereológico de la misma ciudad (167 pacientes en el primero y 264 en el segundo); su edad promedio era 28 años. Utiliza...

  9. Lactococcus piscium: a psychrotrophic lactic acid bacterium with bioprotective or spoilage activity in food-a review.

    Science.gov (United States)

    Saraoui, T; Leroi, F; Björkroth, J; Pilet, M F

    2016-10-01

    The genus Lactococcus comprises 12 species, some known for decades and others more recently described. Lactococcus piscium, isolated in 1990 from rainbow trout, is a psychrotrophic lactic acid bacterium, probably disregarded because most of the strains are unable to grow at 30°C. During the last 10 years, this species has been isolated from a large variety of food: meat, seafood and vegetables, mostly packed under vacuum (VP) or modified atmosphere (MAP) and stored at chilled temperature. Recently, culture-independent techniques used for characterization of microbial ecosystems have highlighted the importance of Lc. piscium in food. Its role in food spoilage varies according to the strain and the food matrix. However, most studies have indicated that Lc. piscium spoils meat, whereas it does not degrade the sensory properties of seafood. Lactococcus piscium strains have a large antimicrobial spectrum, including Gram-positive and negative bacteria. In various seafoods, some strains have a protective effect against spoilage and can extend the sensory shelf-life of the products. They can also inhibit the growth of Listeria monocytogenes, by a cell-to-cell contact-dependent. This article reviews the physiological and genomic characteristics of Lc. piscium and discusses its spoilage or protective activities in food.

  10. Bacterial pneumonia following bone marrow transplantation: HRCT findings Achados de TCAR nas pneumonias bacterianas após transplante de medula óssea

    Directory of Open Access Journals (Sweden)

    Luiz Otávio de Mattos Coelho

    2009-05-01

    Full Text Available OBJECTIVE: To describe HRCT findings in patients with bacterial pneumonia following bone marrow transplantation (BMT. METHODS: This was a retrospective study involving 30 patients diagnosed with bacterial pneumonia in whom HRCT of the chest was performed within 24 h after the onset of symptoms and the diagnosis was confirmed, based on a positive culture of sputum or bronchial aspirate, together with a positive pleural fluid or blood culture, within one week after symptom onset. There were 20 male patients and 10 female patients. The median age was 21 years (range, 1-41 years. The BMT had been performed for the treatment of the following: chronic myeloid leukemia, in 14 cases; severe aplastic anemia, in 6; acute myeloid leukemia, in 4; Fanconi's anemia, in 3; and acute lymphocytic leukemia, in 3. Two radiologists analyzed the HRCT scans and reached their final decisions by consensus. RESULTS: The most common HRCT findings were air-space consolidation (in 60%, small centrilobular nodules (in 50%, ground-glass opacities (in 40%, bronchial wall thickening (in 20%, large nodules (in 20%, pleural lesions (in 16.7% and tree-in-bud opacities (in 10%. The pulmonary lesions were distributed in the central and peripheral areas in 15 patients, whereas they were exclusively peripheral in 11. Lesions were located in the lower and middle lobes of the lung in 22 and 20 patients, respectively. CONCLUSIONS: The most common HRCT findings in our patient sample were air-space consolidation, small centrilobular nodules and ground-glass opacities, most often in the central and peripheral regions of the middle and lower lung zones.OBJETIVO: Descrever os achados de TCAR em pacientes com pneumonia bacteriana após transplante de medula óssea (TMO. MÉTODOS: Estudo retrospectivo com 30 pacientes diagnosticados com pneumonia bacteriana, documentada com TCAR do tórax realizada em até 24 h do início dos sintomas, e com diagnóstico comprovado com base em cultura positiva

  11. POLARIDAD ESTRUCTURAL Y DINAMICA DE POLIMERIZACION DE LA TUBULINA BACTERIANA BTUBA/B DE PROSTHECOBACTER DEJONGEII

    OpenAIRE

    DIAZ CELIS, CESAR DAVID

    2010-01-01

    El heterodímero de α/β-tubulina , la proteína que forma el citoesqueleto de microtúbulos, está presente en todos los eucariontes conocidos, pero nunca ha sido detectado en bacterias o arqueas. Por este motivo, se consideró a la tubulina como una proteína típica del citoesqueleto de los eucariontes. Sin embargo, en el año 2002 se descubrió en el genoma de cuatro especies del género bacteriano Prosthecobacter (división Verrucomicrobia) dos nuevas secuencias de tubulina, btubA y btubB ("bacte...

  12. Pneumonia associada à ventilação mecânica: impacto da multirresistência bacteriana na morbidade e mortalidade Ventilator-associated pneumonia: impact of bacterial multidrug-resistance on morbidity and mortality

    Directory of Open Access Journals (Sweden)

    Paulo José Zimermann Teixeira

    2004-12-01

    Full Text Available INTRODUÇÃO: A pneumonia associada à ventilação mecânica é a infecção hospitalar mais comum nas unidades de terapia intensiva. OBJETIVO: Determinar o impacto da multirresistência dos microorganismos na morbidade e mortalidade dos pacientes com pneumonia associada à ventilação mecânica. MÉTODO: Estudo de coorte retrospectivo. Em 40 meses consecutivos, 91 pacientes sob ventilação mecânica tiveram o diagnóstico de pneumonia. Os casos foram divididos entre causados por microorganismo multirresistente e causados por microorganismo sensível à antibioticoterapia. RESULTADOS: Pneumonia foi causada por microorganismo multirresistente em 75 casos (82,4% e por microorganismo sensível 16 (17,6% deles. As características clínicas e epidemiológicas não foram estatisticamente diferentes entre os grupos. O Staphylococcus aureus foi responsável por 27,5% dos episódios de pneumonia associada à ventilação mecânica e a Pseudomonas aeruginosa por 17,6%. A doença foi de início recente em 33 pacientes (36,3% e de início tardio em 58 deles (63,7%. Os tempos de ventilação mecânica, de internação em unidade de terapia intensiva e de internação hospitalar total não diferiram. O tratamento empírico foi considerado inadequado em 42 pacientes com pneumonia por microorganismo multirresistente (56% e em 4 com pneumonia por microorganismo sensível (25% (p = 0,02. Óbito ocorreu em 46 pacientes com a pneumonia por microorganismo multirresistente (61,3%, e em 4 daqueles com pneumonia por microorganismo sensível (25% (p = 0,008. CONCLUSÃO: A multirresistência bacteriana não determinou nenhum impacto na morbidade, mas esteve associada à maior mortalidade.BACKGROUND: Ventilator-associated pneumonia is the most common nosocomial infection occurring in intensive care units. OBJECTIVE: To determinate the impact of multidrug-resistant bacteria on morbidity and mortality in patients with ventilator-associated pneumonia. METHOD

  13. Acute bacterial meningitis caused by Streptococcus pneumoniae resistant to the antimicrobian agents and their serotypes Meningite bacteriana aguda por Streptococcus pneumoniae resistente aos antimicrobianos e seus sorotipos

    OpenAIRE

    Andrea Maciel de Oliveira Rossoni; Libera Maria Dalla Costa; Denize Bonato Berto; Sônia Santos Farah; Marilene Gelain; Maria Cristina de Cunto Brandileone; Vitor Hugo Mariano Ramos; Sergio Monteiro de Almeida

    2008-01-01

    The main objectives of this study are to evaluate the resistance rates of Streptococcus pneumonia to penicillin G, ceftriaxone and vancomycin in patients with meningitis; to analyze possible risk factors to the antimicrobian resistance; to describe the serotypes detected and to suggest an initial empirical treatment for meningitis. The sensitiveness and serotypes of all isolated S. pneumoniae of patients with acute bacterial meningitis received by the Paraná State Central Laboratory from Apri...

  14. Receptores de la prostaglandina E2 implicados en los trastornos motores digestivos y la fiebre inducidos por endotoxinas en la oveja: Papel de los macrófagos

    OpenAIRE

    Gimeno Soriano, Aurora; Plaza Carrión, Miguel Ángel; Castro López, Marta

    2014-01-01

    El objetivo general de este trabajo ha sido el estudio de los mecanismos fisiopatológicos implicados en la fiebre y en las alteraciones motoras digestivas inducidas por una endotoxina bacteriana: el lipopolisacárido (LPS) de Escherichia coli en la oveja. Se ha estudiado la participación de los receptores de la prostaglandina (PG) E2 (EP1, EP2, EP3 y EP4), los tipos celulares que están implicados en la síntesis y liberación de PGs en el hipotálamo y bulbo raquídeo y la posible participación de...

  15. Artritis séptica de cadera por Haemophilus influenzae tipo F en la infancia: a propósito de un caso

    OpenAIRE

    2013-01-01

    La artritis séptica de cadera es una infección aguda, predominantemente de etiología bacteriana. A pesar de que el patógeno principal en cualquier grupo de edad es Staphylococcus aureus, existen otros microorganismos potencialmente patógenos. Describimos el caso de una paciente de 18 meses con artritis séptica de cadera por un agente causal infrecuente (Haemophilus influenzae tipo f) de buena evolución. Este caso pone de manifiesto la importancia de considerar otros agentes etiológicos menos ...

  16. Valorización de residuos agroindustriales para la obtención de liquenisina por Bacillus licheniformis AL 1.1

    OpenAIRE

    Coronel León, Jonathan

    2015-01-01

    La cepa bacteriana AL 1.1 se aisló de una muestra de suelo de la isla Decepción del continente Antártico. Inicialmente se observó que dicha cepa tenía la capacidad de reducir la tensión superficial del medio, por lo que fue seleccionada para realizar la presente tesis doctoral. Después de confirmar la identificación del aislado como un Bacillus licheniformis se caracterizó el biotensioactivo (BT) producido como liquenisina (LchAL1.1). El estudio de las propiedades físico-químicas de la Lc...

  17. Estudos por ancoramento e dinâmica molecular de potenciais inibidores da Nucleosídeo Hidrolase de Bacillus anthracis

    OpenAIRE

    Guimarães, Ana Paula

    2014-01-01

    A enzima nucleosídeo hidrolase (NH) se encontra largamente distribuída na natureza e, por não ter sido encontrada ainda em mamíferos, tem sido vista como um alvo ideal para a quimioterapia seletiva de doenças parasitárias e infecções bacterianas como o antraz. Apesar da disponibilidade de quimioterapia contra o antraz atualmente, o risco de desenvolvimento de resistência contra esses fármacos está sempre presente. Além disso, é muito provável que esses fármacos sejam ineficientes contra cepas...

  18. Evaluación de la transferencia de oxígeno en cultivos con lactococcus lactis empleando un sistema de fermentación con aireación externa

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    Andrea Soler

    2010-10-01

    Full Text Available Título en inglés: Evaluating oxygen transfer in a Lactococcus lactis cultures using an external aeration fermentation system (EAFS Resumen En fermentaciones aerobias el oxígeno, como aceptor terminal de electrones en el proceso de respiración, comúnmente se constituye en limitante debido entre otros factores al diseño del biorreactor (factores geométricos, a las condiciones de operación de los fermentadores (condiciones ambientales requeridas en el cultivo, potencia transferida al cultivo por el sistema de agitación, propiedades del medio líquido, demanda de oxígeno por parte del microorganismo, sistema de aireación (concentración de oxígeno en el gas, solubilidad del oxígeno. La limitación de oxígeno se refleja en la fermentación con Lactococcus lactis cepa IBUN 34.1, en que presenta una baja disponibilidad de oxígeno desde muy temprano en la fase exponencial del cultivo. Para superar estas limitaciones se diseñó y desarrolló un sistema de suministro de oxígeno de alta tasa de transferencia, consistente en un sistema de fermentación con aireación externa (SFAE, el cual es comparado en este trabajo con el sistema tradicional de fermentador agitado dotado con dos turbinas tipo Rushton y aireación por difusor interno. En este trabajo se evalúa la operación del SFAE, se seleccionan y estudian algunas variables operacionales y su efecto sobre la transferencia de oxígeno gas-líquido. Los resultados indican que las variables que tienen efecto significativo sobre el coeficiente volumétrico global de transferencia de masa kLa son la agitación y el flujo de medio de cultivo que circula por el aireador externo denominado flujo de recirculación. Los valores de kLa obtenidos indican que con el fermentador convencional con aireación interna el mayor valor de kLa alcanzado fue de 40,68 (h-1, en tanto que con el SFAE se alcanzaron valores de 63,18 (h-1. Palabras clave: biorreactores; kLa; transferencia de ox

  19. Detection and characterization of bacteriocin-producing Lactococcus lactis strains Detecção e caracterização de Lactococcus lactis produtores de bacteriocinas

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    Izildinha Moreno

    1999-04-01

    Full Text Available One hundred sixty seven strains of Lactococcus lactis were screened for bacteriocin production by well diffusion assay of GM17 agar. Fourteen (8.4% produced antimicrobial activity other than organic acids, bacteriophages or hydrogen peroxide. The frequency of bacteriocin production ranged from 2% in L. lactis subsp. cremoris up to 12% in L. lactis subsp. lactis. Antimicrobial activities were not observed in any strain of L. lactis subsp. lactis var. diacetylactis. Among thirteen bacteriocin-producing strains and two nisin-producing strains (L. lactis subsp. lactis ATCC 11454 and L. lactis subsp. lactis CNRZ 150, eight (53% were characterized as lactose-positive (Lac+ and proteinase-negative (Prt-. The bacteriocin-producing cultures were also characterized on the basis of plasmid content. All strains had 2 to 7 plasmids with molecular weights varying from 0.5 to 28.1 Mdal. Four strains (ITAL 435, ITAL 436, ITAL 437 and ITAL 438 showed identical profiles and the other were quite distinct.Um total de 167 linhagens de L. lactis foi selecionado para os testes de produção de bacteriocinas pelo método de difusão em poços em agar GM17. Desse total, 14 (8.4% produziram substâncias inibidoras que não foram associadas com ácidos orgânicos, peróxido de hidrogênio e bacteriófagos. A frequência de produção de bacteriocinas variou de 2% em L. lactis subsp. cremoris a 12% em L. lactis subsp. lactis. Nenhuma das linhagens de L. lactis subsp. lactis var. diacetylactis produziu substâncias inibidoras. De 13 linhagens produtoras de bacteriocinas e duas de nisina (L. lactis subsp. lactis ATCC 11454 e L. lactis subsp. lactis CNRZ 150, 8 (53% foram caracterizadas como lactose-positivas (Lac+ e proteinase-negativas (Prt-. As linhagens produtoras de bacteriocinas também foram caracterizadas no seu conteúdo de plasmídios. Elas apresentaram de 2 a 7 plasmídios, com pesos moleculares aproximados de 0.5 a 28.1 Mdal. Quatro linhagens (ITAL 435, ITAL 436

  20. Bacterial Levan: tecnological aspects, characteristics and production/ Levana Bacteriana: aspectos tecnológicos, características e produção

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    Crispin Humberto Garcia-Cruz

    2005-06-01

    Full Text Available Levan is an exopolysaccharide, constituted by fructose units, ? (2- 6 linked, obtained by transfructosilation reaction during microorganisms fermentation in a sucrose rich but wi thout glucose, fructose or mixtures in the culture media. Bacterial levan production is a good alternative fructose source, besides having certain functional characteristics in the human body, such as a hypocholesterolemic and an anticarcinogenic agent. In the food industry, levan can be used to fix colors and flavors, as well as thickening and stabilizing agent. In the bacterial levan production, Zymomonas mobilis has been considered the best possible alternative, since it uses as carbon source sucrose or industrial residues that contain this sugar, in different concentrations, in a mineral salts rich medium. Levan production is not only influenced by carbon source and its concentration, but also by pH, temperature and type of salts. Moreover, the oxygenation of the fermentation medium, also affect the characteristics of the molecule and the cellular growth. In this revision some important topics concerning the bacterial levan production are presented.Levana é um exopolissacarídeo, constituído por unidades de frutose, unidas através de ligações ? (2- 6, obtido pela reação de transfrutosilação durante a fermentação de microrganismos em meio rico em sacarose mas não em frutose, glucose ou misturas de ambas. Pesquisas sobre bactérias produtoras de levana vêm sendo implementadas, uma vez que a mesma é uma fonte alternativa de frutose, além de apresentar características funcionais no organismo humano, como agente hipocolesterolêmico e anticarcinogênico. Na indústria de alimentos a levana pode ser empregada como fixador de cores e sabores, bem como espessante e estabilizante de vários alimentos. Das bactérias produtoras de levana, Zymomonas mobilis tem sido a melhor alternativa, uma vez que usa como fonte de carbono a sacarose ou resíduos industriais

  1. Adequação da contagem de células somáticas e da contagem bacteriana total em leite cru refrigerado aos parâmetros da legislação

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    G.A. Bozo

    2013-04-01

    Full Text Available O objetivo deste trabalho foi adequar a qualidade do leite cru refrigerado de cinco propriedades leiteiras aos parâmetros microbiológicos e de contagem de células somáticas (CCS estabelecidos pela legislação estadual do Paraná. As propriedades leiteiras estudadas foram monitoradas durante sete meses após a implantação de boas práticas de ordenha e de recomendações quanto ao tratamento de mastites e à manutenção e higienização de equipamentos de ordenha. Antes da adoção das recomendações, a contagem bacteriana total (CBT média era de 1,36 x 10(6UFC/mL e a CCS média, de 1,87 x 10(6/mL. Todas as propriedades atingiram os padrões estabelecidos para CBT, com redução média de 93,4%. A redução de CCS foi, em média, 74,3%. Apenas três propriedades atingiram os valores estabelecidos para CCS. As demais atingiram valores muito próximos ao limite. A adequação aos padrões de CBT e CCS gerou aumento na renda mensal, em razão do pagamento por qualidade do produto, entre R$120,00 e R$828,00, de acordo com a produção de cada propriedade.

  2. Effect of a 0.5% chlorhexidine gel on dental plaque superinfecting microorganisms in mentally handicapped patients Efeito do gel de clorexidina a 0,5% em microrganismos superinfectantes da placa bacteriana de portadores de necessidades especiais

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    Cláudio Mendes Pannuti

    2003-09-01

    Full Text Available A randomized clinical trial was conducted to investigate the effect of a 0.5% chlorhexidine (CHX gel on dental plaque superinfecting microorganisms in mentally handicapped patients. Thirty inmates from the institution "Casas André Luiz" were assigned to either test group (CHX gel, n = 15 or control group (placebo gel, n = 15. The gel was administered over a period of 8 weeks. Supragingival plaque samples were collected at baseline, after gel use (8 weeks and 16 weeks after baseline. The presence of Gram-negative Enterobacteriaceae, Staphylococcus and yeasts was evaluated. No significant growth of any superinfecting microorganism was observed in the CHX group, when compared to the placebo group. The results indicated that the 0.5% chlorhexidine gel did not produce an undesirable shift in these bacterial populations.Foi conduzido um ensaio clínico aleatório com objetivo de investigar o efeito do gel de clorexidina (CHX a 0,5% sobre microorganismos superinfectantes da placa bacteriana de pacientes especiais. Trinta internos da instituição "Casas André Luiz" foram aleatoriamente divididos em grupo teste (gel de CHX, n = 15 e controle (gel placebo, n = 15. O gel foi utilizado por oito semanas. Amostras de placa supragengival foram coletadas no início do estudo, após o uso do gel (oito semanas e 16 semanas após o início do estudo. Foi avaliada a presença de bacilos entéricos Gram-negativos, Staphylococcus e leveduras. Não houve diferença entre os grupos quanto à presença desses microorganismos em qualquer momento do estudo. Os resultados indicam que o gel de CHX não provocou mudanças significativas na composição desses microorganismos.

  3. Clinical outcome of neonatal bacterial meningitis according to birth weight Evolução clínica da meningite bacteriana neonatal de acordo com o peso de nascimento

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    Vera Lúcia Jornada Krebs

    2007-12-01

    Full Text Available OBJECTIVE: To describe the clinical outcome and the complications of bacterial meningitis according to birth weight of out born neonates admitted in intensive care unit during an 11 year-period. METHOD: Eighty-seven newborns were studied. Thirty-four infants were low birth weight newborn and 53 presented birth weight > " 2500 g. The clinical data were obtained through the analysis of patients’ files. Fisher’s exact test, the c² and the Mann-Whitney test were applied. RESULTS: Neurological symptoms were more common in infants weighed > " 2500 g (pOBJETIVO: Descrever a evolução clínica e as complicações da meningite bacteriana de acordo com o peso de nascimento em recém-nascidos admitidos em unidade de terapia intensiva externa durante o período de 11 anos. MÉTODO: Foram estudados 87 neonatos, dos quais 34 foram recém-nascidos de baixo peso e 53 apresentaram peso > " 2500 g. Os dados clínicos foram obtidos por análise dos prontuários médicos. Foram realizados teste exato de Fisher, teste do c² e teste de Mann-Whitney. RESULTADOS: Os sintomas neurológicos foram mais comuns em neonatos com peso > " 2500 g (p<0,05 . As complicações ocorreram na metade dos casos em ambos os grupos, com mortalidade global de 11.5%. CONCLUSÃO: A freqüência de complicações foi alta em ambos os grupos, independentemente do peso de nascimento. Não houve associação entre óbito e peso de nascimento. Os neonatos com cultura de líquor positiva apresentaram pior prognóstico.

  4. Nursing staff knowledge of multi-resistant bacterial infections Conocimiento de los profesionales de enfermería referente a la resistencia bacteriana a múltiples drogas Conhecimento dos profissionais de enfermagem referente à resistencia bacteriana a múltiplas drogas

    Directory of Open Access Journals (Sweden)

    Josely Pinto de Moura

    2007-09-01

    Full Text Available OBJECTIVE: To assess professional nurses', associate degree prepared nurses', licensed practical nurses', and nursing assistants' knowledge of the causes of multi-resistant bacterial infections, the risks theses infections pose to health care providers, the chain of transmission of these infections, and patients' susceptibility to colonization of these multi-resistant bacterial infections. METHODS: This descriptive study was conducted in a major general hospital in Minas Gerais, Brazil. The sample consisted of 42 nursing staff from a medical clinical unit. Descriptive statistics were used to analyze and present the data. RESULTS: Nursing staff had unsatisfactory knowledge of the causes of multi-resistant bacterial infections, the chain of transmission of multi-resistant bacterial infections, and patients' susceptibility to colonization of multi-resistant bacterial infections. However, the majority of participants had some knowledge about the risks that multi-resistant bacterial infections posed to health care providers. CONCLUSION: Lack of knowledge among nursing staff compromise adherence to preventive measures and nursing management of multi-resistant bacterial infections.OBJETIVO: Evaluar el conocimiento de los enfermeros, técnicos y auxiliares de enfermería de un hospital general de Minas Gerais, en cuanto a las causas da multirresistencia bacteriana, los riesgos para el equipo de salud, el modo de transmisión y susceptibilidad de los pacientes a la colonización por bacterias resistentes a múltiples drogas. MÉTODOS: Realizado en la clínica médica, fueron entrevistados 42 profesionales de enfermería encontrados en la unidad. En este estudio de tipo cuantitativo se realizó un análisis descriptivo de sus datos, utilizándose la estadística descriptiva con base en el cálculo de porcentaje, los cuales fueron presentados en tablas. RESULTADOS: Los profesionales demostraron conocimiento restricto y limitado sobre la tem

  5. Insights into new bacteriophages of Lactococcus garvieae belonging to the family Podoviridae.

    Science.gov (United States)

    Ghasemi, Seyed Mahdi; Bouzari, Majid; Shaykh Baygloo, Nima; Chang, Hyo-Ihl

    2014-11-01

    Lactococcus garvieae is an emerging pathogen responsible for lactococcosis, a serious disease in trout aquaculture. The identification of new bacteriophages against L. garvieae strains may be an effective way to fight this disease and to study the pathogen's biology. Three L. garvieae phages, termed WP-1, WWP-2 and SP-2, were isolated from different environments, and their morphological features, genome restriction profiles and structural protein patterns were studied. Random cloning of HindIII-cut fragments was performed, and the fragments were partially sequenced for each phage. Although slight differences were observed by transmission electron microscopy, all of the phages had hexagonal heads and short non-contractile tails and were classified as members of the family Podoviridae. Restriction digestion analysis of the nucleic acids of the different phages revealed that the HindIII and AseI digests produced similar DNA fragment patterns. Additionally, SDS-PAGE analysis indicated that the isolated phages have similar structural proteins. The sequence BLAST results did not show any significant similarity with other previously identified phages. To the best of our knowledge, this study provides the first molecular characterization of L. garvieae phages.

  6. Mode of action of lactococcin R produced by Lactococcus lactis R.

    Science.gov (United States)

    Yildirim, Zeliha; Yildirim, Metin; Johnson, Michael G

    2004-04-01

    We investigated the mode of action and factors affecting adsorption of lactoccocin R produced by Lactococcus lactis R. It was found that lactococcin R adsorbed to all Gram-positive but not to the Gram-negative bacteria tested and its adsorption was dependent on pH. It was observed that the binding of lactococcin R was prevented by anions of several salts (Cl-, PO4(-3)) and lipoteichoic acid. Pretreatments of sensitive cells and cell walls with detergents, organic solvents or enzymes did not reduce subsequent binding of lactococcin R. However, treatment of cell wall preparations with methanol:chloroform and hot 20% trichloroacetic acid (TCA) caused such walls to lose their ability to adsorb lactococcin R. Sensitive cells treated with lactococcin R lost high amounts of intracellular K+ ions, UV-absorbing materials and became more permeable to o-nitrophenol-beta-D-glactopyranoside (ONPG). In addition, different lactococcin R concentrations (0-2560 AU/mL) decreased the colony counts of Listeria monocytogenes by 99% and also a reduction in the absorbance values. These results show that the mode of action of lactococcin R is bactericidal rather than bacteriostatic.

  7. Transcriptomic profile of aguR deletion mutant of Lactococcus lactis subsp. cremoris CECT 8666

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    Beatriz del Rio

    2015-12-01

    Full Text Available Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14 is a dairy strain that catabolizes agmatine (a decarboxylated derivative of arginine into the biogenic amine putrescine by the agmatine deiminase (AGDI pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are responsible for the deamination of agmatine to putrescine and are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC [1]. aguR encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC [2], which is also transcriptionally regulated by carbon catabolic repression (CCR via glucose, but not by other sugars such as lactose and galactose [1,3]. Here we report the transcriptional profiling of the aguR gene deletion mutant (L. lactis subsp. cremoris CECT 8666 ∆aguR [2] compared to the wild type strain, both grown in M17 medium with galactose as carbon source and supplemented with agmatine. The transcriptional profiling data of AguR-regulated genes were deposited in the Gene Expression Omnibus (GEO database under accession no. GSE59514.

  8. Sequencing and transcriptional analysis of the biosynthesis gene cluster of putrescine-producing Lactococcus lactis.

    Science.gov (United States)

    Ladero, Victor; Rattray, Fergal P; Mayo, Baltasar; Martín, María Cruz; Fernández, María; Alvarez, Miguel A

    2011-09-01

    Lactococcus lactis is a prokaryotic microorganism with great importance as a culture starter and has become the model species among the lactic acid bacteria. The long and safe history of use of L. lactis in dairy fermentations has resulted in the classification of this species as GRAS (General Regarded As Safe) or QPS (Qualified Presumption of Safety). However, our group has identified several strains of L. lactis subsp. lactis and L. lactis subsp. cremoris that are able to produce putrescine from agmatine via the agmatine deiminase (AGDI) pathway. Putrescine is a biogenic amine that confers undesirable flavor characteristics and may even have toxic effects. The AGDI cluster of L. lactis is composed of a putative regulatory gene, aguR, followed by the genes (aguB, aguD, aguA, and aguC) encoding the catabolic enzymes. These genes are transcribed as an operon that is induced in the presence of agmatine. In some strains, an insertion (IS) element interrupts the transcription of the cluster, which results in a non-putrescine-producing phenotype. Based on this knowledge, a PCR-based test was developed in order to differentiate nonproducing L. lactis strains from those with a functional AGDI cluster. The analysis of the AGDI cluster and their flanking regions revealed that the capacity to produce putrescine via the AGDI pathway could be a specific characteristic that was lost during the adaptation to the milk environment by a process of reductive genome evolution.

  9. Transcriptomic profile of aguR deletion mutant of Lactococcus lactis subsp. cremoris CECT 8666.

    Science.gov (United States)

    Del Rio, Beatriz; Linares, Daniel M; Redruello, Begoña; Martin, Maria Cruz; Fernandez, Maria; de Jong, Anne; Kuipers, Oscar P; Ladero, Victor; Alvarez, Miguel A

    2015-12-01

    Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14) is a dairy strain that catabolizes agmatine (a decarboxylated derivative of arginine) into the biogenic amine putrescine by the agmatine deiminase (AGDI) pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are responsible for the deamination of agmatine to putrescine and are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC[1]. aguR encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC[2], which is also transcriptionally regulated by carbon catabolic repression (CCR) via glucose, but not by other sugars such as lactose and galactose [1], [3]. Here we report the transcriptional profiling of the aguR gene deletion mutant (L. lactis subsp. cremoris CECT 8666 ∆aguR) [2] compared to the wild type strain, both grown in M17 medium with galactose as carbon source and supplemented with agmatine. The transcriptional profiling data of AguR-regulated genes were deposited in the Gene Expression Omnibus (GEO) database under accession no. GSE59514.

  10. Improved viability of bifidobacteria in fermented milk by cocultivation with Lactococcus lactis subspecies lactis.

    Science.gov (United States)

    Odamaki, T; Xiao, J Z; Yonezawa, S; Yaeshima, T; Iwatsuki, K

    2011-03-01

    The poor survival of probiotic bacteria in commercial yogurts may limit their potential to exert health benefits in humans. The objective was to improve the survival of bifidobacteria in fermented milk. Cocultivation with some strains of Lactococcus lactis ssp. lactis improved the survival of bifidobacteria in fermented milk during refrigerated storage. Studies on one strain, Lc. lactis ssp. lactis MCC866, showed that the concentrations of dissolved oxygen were kept lower in the cocultivated fermented milk during storage compared with monocultured Bifidobacterium longum BB536 or samples cocultured with another noneffective Lc. lactis ssp. lactis strain. Degradation of genomic DNA was suppressed in the cocultivating system with Lc. lactis ssp. lactis MCC866. Several genes that participated in protection from active oxygen species (e.g., genes coding for alkyl hydroperoxide reductase and Fe(2+) transport system) were expressed at higher levels during refrigerated storage in Lc. lactis ssp. lactis MCC 866 compared with another noneffective Lc. lactis ssp. lactis strain. Concentration of free iron ion was also lower in supernatants of fermented milk cocultivated with B. longum BB536 and Lc. lactis ssp. lactis MCC866. These results suggest that Lc. lactis ssp. lactis MCC 866 is potentially superior in reducing oxygen damage and consequently improves the survival of bifidobacteria in the cocultivating system. This cocultivation system is of industrial interest for producing fermented milk containing viable bifidobacteria with long shelf life.

  11. Molecular Characterization of a Recombinant Manganese Superoxide Dismutase from Lactococcus lactis M4

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    Boon Hooi Tan

    2014-01-01

    Full Text Available A superoxide dismutase (SOD gene of Lactococcus lactis M4 was cloned and expressed in a prokaryotic system. Sequence analysis revealed an open reading frame of 621 bp which codes for 206 amino acid residues. Expression of sodA under T7 promoter exhibited a specific activity of 4967 U/mg when induced with 1 mM of isopropyl-β-D-thiogalactopyranoside. The recombinant SOD was purified to homogeneity by immobilised metal affinity chromatography and Superose 12 gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot analyses of the recombinant SOD detected a molecular mass of approximately 27 kDa. However, the SOD was in dimer form as revealed by gel filtration chromatography. The purified recombinant enzyme had a pI of 4.5 and exhibited maximal activity at 25°C and pH 7.2. It was stable up to 45°C. The insensitivity of this lactococcal SOD to cyanide and hydrogen peroxide established that it was a MnSOD. Although it has 98% homology to SOD of L. lactis IL1403, this is the first elucidated structure of lactococcal SOD revealing active sites containing the catalytic manganese coordinated by four ligands (H-27, H-82, D-168, and H-172.

  12. Use of Lactococcus lactis to enrich sourdough bread with γ-aminobutyric acid.

    Science.gov (United States)

    Bhanwar, Seema; Bamnia, Meenakshi; Ghosh, Moushumi; Ganguli, Abhijit

    2013-02-01

    Fried sourdough bread (bhatura) with an elevated amount of γ-aminobutyric acid (GABA) was produced using lactic acid bacteria (LAB). The LAB starter was screened and isolated from pickled yam showing highest GABA content and was identified as Lactococcus lactis subsp. lactis. The maximum GABA production in de Man Rogosa Sharpe (MRS) media supplemented with monosodium glutamate (MSG) was 110 mg/100 ml at pH 5, and 1-3% NaCl did not change the production of GABA significantly (p>0.05). When MSG was replaced with Vigna mungo in sourdough, the amount of GABA for bhatura was 226.22 mg/100 g representing about 10-fold increase. A sensory evaluation resulted as the overall general acceptability of bhatura to be 4.91 ± 0.03 on a five-point hedonic scale. Thus, the results indicated the potential of L. lactis as a LAB starter for the production of GABA-enriched bhatura. Although other physiological effects can be expected in the product, animal and clinical studies are mandatory prior to application of this food.

  13. Improvement of bovine ß-lactoglobulin production and secretion by Lactococcus lactis

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    S. Nouaille

    2005-03-01

    Full Text Available The stabilizing effects of staphylococcal nuclease (Nuc and of a synthetic propeptide (LEISSTCDA, hereafter called LEISS on the production of a model food allergen, bovine ß-lactoglobulin (BLG, in Lactococcus lactis were investigated. The fusion of Nuc to BLG (Nuc-BLG results in higher production and secretion of the hybrid protein. When LEISS was fused to BLG, the production of the resulting protein LEISS-BLG was only slightly improved compared to the one obtained with Nuc-BLG. However, the secretion of LEISS-BLG was dramatically enhanced (~10- and 4-fold higher than BLG and Nuc-BLG, respectively. Finally, the fusion of LEISS to Nuc-BLG resulting in the protein LEISS-Nuc-BLG led to the highest production of the hybrid protein, estimated at ~8 µg/ml (~2-fold higher than Nuc-BLG. In conclusion, the fusions described here led to the improvement of the production and secretion of BLG. These tools will be used to modulate the immune response against BLG via delivery of recombinant lactococci at the mucosal level, in a mouse model of cow's milk allergy.

  14. The cmbT gene encodes a novel major facilitator multidrug resistance transporter in Lactococcus lactis.

    Science.gov (United States)

    Filipic, Brankica; Golic, Natasa; Jovcic, Branko; Tolinacki, Maja; Bay, Denice C; Turner, Raymond J; Antic-Stankovic, Jelena; Kojic, Milan; Topisirovic, Ljubisa

    2013-01-01

    Functional characterization of the multidrug resistance CmbT transporter was performed in Lactococcus lactis. The cmbT gene is predicted to encode an efflux protein homologous to the multidrug resistance major facilitator superfamily. The cmbT gene (1377 bp) was cloned and overexpressed in L. lactis NZ9000. Results from cell growth studies revealed that the CmbT protein has an effect on host cell resistance to lincomycin, cholate, sulbactam, ethidium bromide, Hoechst 33342, sulfadiazine, streptomycin, rifampicin, puromycin and sulfametoxazole. Moreover, in vivo transport assays showed that overexpressed CmbT-mediated extrusion of ethidium bromide and Hoechst 33342 was higher than in the control L. lactis NZ9000 strain. CmbT-mediated extrusion of Hoechst 33342 was inhibited by the ionophores nigericin and valinomycin known to dissipate proton motive force. This indicates that CmbT-mediated extrusion is based on a drug-proton antiport mechanism. Taking together results obtained in this study, it can be concluded that CmbT is a novel major facilitator multidrug resistance transporter candidate in L. lactis, with a possible signaling role in sulfur metabolism.

  15. Interaction of benzoate pyrimidine analogues with class 1A dihydroorotate dehydrogenase from Lactococcus lactis

    DEFF Research Database (Denmark)

    Wolfe, Abigail E; Thymark, Majbritt; Gattis, Samuel G;

    2007-01-01

    Dihydroorotate dehydrogenases (DHODs) catalyze the oxidation of dihydroorotate to orotate in the only redox reaction in pyrimidine biosynthesis. The pyrimidine binding sites are very similar in all structurally characterized DHODs, suggesting that the prospects for identifying a class-specific in......Dihydroorotate dehydrogenases (DHODs) catalyze the oxidation of dihydroorotate to orotate in the only redox reaction in pyrimidine biosynthesis. The pyrimidine binding sites are very similar in all structurally characterized DHODs, suggesting that the prospects for identifying a class......-specific inhibitor directed against this site are poor. Nonetheless, two compounds that bind specifically to the Class 1A DHOD from Lactococcus lactis, 3,4-dihydroxybenzoate (3,4-diOHB) and 3,5-dihydroxybenzoate (3,5-diOHB), have been identified [Palfey et al. (2001) J. Med. Chem. 44, 2861-2864]. The mechanism...... of inhibitor binding to the Class 1A DHOD from L. lactis has now been studied in detail and is reported here. Titrations showed that 3,4-diOHB binds more tightly at higher pH, whereas the opposite is true for 3,5-diOHB. Isothermal titration calorimetry and absorbance spectroscopy showed that 3,4-diOHB ionizes...

  16. Procedure for quantifiable assessment of nutritional parameters influencing nisin production by Lactococcus lactis subsp. lactis.

    Science.gov (United States)

    Chandrapati, S; O'Sullivan, D J

    1998-08-27

    A modified rapid plate assay procedure was developed, that allowed quantifiable measurement of nisin production by Lactococcus lactis growing directly on agar media. Using this direct plate assay, several nutritional parameters were assessed for their influence on nisin production (as distinct from their influence on growth) by L. lactis subsp. lactis ATCC 11454 growing on standard M17 based media over 3 and 6 h incubation periods. Glucose was found to be the optimal carbon source tested, with glycerol having the greatest suppressive effect. The addition of salts suppressed nisin production on a per cell basis, except MnCl2. This direct plate method proved to be a good pilot assay for rapidly and quantifiably investigating the initial effects of different parameters on nisin production by L. lactis, prior to conducting more intensive broth batch culture assays. The data obtained in this study indicate that certain nutritional parameters can impose a repressive effect on nisin production. Elucidation of how these parameters control the amount of nisin produced will provide further insight into the regulation of nisin biosynthesis in L. lactis.

  17. Enhance nisin yield via improving acid-tolerant capability of Lactococcus lactis F44

    Science.gov (United States)

    Zhang, Jian; Caiyin, Qinggele; Feng, Wenjing; Zhao, Xiuli; Qiao, Bin; Zhao, Guangrong; Qiao, Jianjun

    2016-01-01

    Traditionally, nisin was produced industrially by using Lactococcus lactis in the neutral fermentation process. However, nisin showed higher activity in the acidic environment. How to balance the pH value for bacterial normal growth and nisin activity might be the key problem. In this study, 17 acid-tolerant genes and 6 lactic acid synthetic genes were introduced in L. lactis F44, respectively. Comparing to the 2810 IU/mL nisin yield of the original strain F44, the nisin titer of the engineered strains over-expressing hdeAB, ldh and murG, increased to 3850, 3979 and 4377 IU/mL, respectively. These engineered strains showed more stable intracellular pH value during the fermentation process. Improvement of lactate production could partly provide the extra energy for the expression of acid tolerance genes during growth. Co-overexpression of hdeAB, murG, and ldh(Z) in strain F44 resulted in the nisin titer of 4913 IU/mL. The engineered strain (ABGL) could grow on plates with pH 4.2, comparing to the surviving pH 4.6 of strain F44. The fed-batch fermentation showed nisin titer of the co-expression L. lactis strain could reach 5563 IU/mL with lower pH condition and longer cultivation time. This work provides a novel strategy of constructing robust strains for use in industry process. PMID:27306587

  18. Comparative Genomic Analysis of Lactococcus garvieae Strains Isolated from Different Sources Reveals Candidate Virulence Genes

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    Eiji Miyauchi

    2012-01-01

    Full Text Available Lactococcus garvieae is a major pathogen for fish. Two complete (ATCC 49156 and Lg2 and three draft (UNIUD074, 8831, and 21881 genome sequences of L. garvieae have recently been released. We here present the results of a comparative genomic analysis of these fish and human isolates of L. garvieae. The pangenome comprised 1,542 core and 1,378 dispensable genes. The sequenced L. garvieae strains shared most of the possible virulence genes, but the capsule gene cluster was found only in fish-pathogenic strain Lg2. The absence of the capsule gene cluster in other nonpathogenic strains isolated from mastitis and vegetable was also confirmed by PCR. The fish and human isolates of L. garvieae contained the specific two and four adhesin genes, respectively, indicating that these adhesion proteins may be involved in the host specificity differences of L. garvieae. The discoveries revealed by the pangenomic analysis may provide significant insights into the biology of L. garvieae.

  19. Cloning and DNA sequence analysis of a Lactococcus bacteriophage lysin gene.

    Science.gov (United States)

    Shearman, C; Underwood, H; Jury, K; Gasson, M

    1989-08-01

    A gene for the lysin of Lactococcus lactis bacteriphage phi vML3 was cloned using an Escherichia coli/bacteriophage lambda host-vector system. The gene was detected by its expression of antimicrobial activity against L. lactis cells in a bioassay. The cloned fragment was analysed by sub-cloning on to E. coli plasmid vectors and by restriction endonuclease and deletion mapping. Its entire DNA sequence was determined and an open reading frame for the lysin structural gene was identified. The sequenced lysin gene would express a protein of 187 amino acids with a molecular weight of 21,090, which is in good agreement with that of a protein detected after in vitro transcription and translation of DNA encoding the gene. Expression of the lysin gene in E. coli and B. subtilis from an adjacent bacteriophage promoter was readily detected but in L. lactis expression of lysin was found to be lethal. The bacteriophage phi vML3 lysin had sequence homology with protein 15 of B. subtilis bacteriophage PZA. This protein is involved in DNA packaging during bacteriophage maturation rather than in host cell lysis. The cloning and analysis of the phi vML3 lysin gene is of importance in further understanding lactic streptococcal bacteriophages, for the development of positive selection vectors and for biotechnological applications of relevance to the dairy industry.

  20. Heterologous protein secretion in Lactococcus lactis: a novel antigen delivery system

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    Langella P.

    1999-01-01

    Full Text Available Lactic acid bacteria (LAB are Gram-positive bacteria and are generally regarded as safe (GRAS organisms. Therefore, LAB could be used for heterologous protein secretion and they are good potential candidates as antigen delivery vehicles. To develop such live vaccines, a better control of protein secretion is required. We developed an efficient secretion system in the model LAB, Lactococcus lactis. Staphylococcal nuclease (Nuc was used as the reporter protein. We first observed that the quantity of secreted Nuc correlated with the copy number of the cloning vector. The nuc gene was cloned on a high-copy number cloning vector and no perturbation of the metabolism of the secreting strain was observed. Replacement of nuc native promoter by a strong lactococcal one led to a significant increase of nuc expression. Secretion efficiency (SE of Nuc in L. lactis was low, i.e., only 60% of the synthesized Nuc was secreted. Insertion of a synthetic propeptide between the signal peptide and the mature moiety of Nuc increased the SE of Nuc. On the basis of these results, we developed a secretion system and we applied it to the construction of an L. lactis strain which secretes a bovine coronavirus (BCV epitope-protein fusion (BCV-Nuc. BCV-Nuc was recognized by both anti-BCV and anti-Nuc antibodies. Secretion of this antigenic fusion is the first step towards the development of a novel antigen delivery system based on LAB-secreting strains.

  1. Lactose-mediated carbon catabolite repression of putrescine production in dairy Lactococcus lactis is strain dependent.

    Science.gov (United States)

    del Rio, Beatriz; Ladero, Victor; Redruello, Begoña; Linares, Daniel M; Fernández, Maria; Martín, Maria Cruz; Alvarez, Miguel A

    2015-06-01

    Lactococcus lactis is the lactic acid bacterial (LAB) species most widely used as a primary starter in the dairy industry. However, several strains of L. lactis produce the biogenic amine putrescine via the agmatine deiminase (AGDI) pathway. We previously reported the putrescine biosynthesis pathway in L. lactis subsp. cremoris GE2-14 to be regulated by carbon catabolic repression (CCR) via glucose but not lactose (Linares et al., 2013). The present study shows that both these sugars repress putrescine biosynthesis in L. lactis subsp. lactis T3/33, a strain isolated from a Spanish artisanal cheese. Furthermore, we demonstrated that both glucose and lactose repressed the transcriptional activity of the aguBDAC catabolic genes of the AGDI route. Finally, a screening performed in putrescine-producing dairy L. lactis strains determined that putrescine biosynthesis was repressed by lactose in all the L. lactis subsp. lactis strains tested, but in only one L. lactis subsp. cremoris strain. Given the obvious importance of the lactose-repression in cheese putrescine accumulation, it is advisable to consider the diversity of L. lactis in this sense and characterize consequently the starter cultures to select the safest strains.

  2. Time-resolved genetic responses of Lactococcus lactis to a dairy environment.

    Science.gov (United States)

    Bachmann, Herwig; de Wilt, Leonie; Kleerebezem, Michiel; van Hylckama Vlieg, Johan E T

    2010-05-01

    Lactococcus lactis is one of main bacterial species found in mixed dairy starter cultures for the production of semi-hard cheese. Despite the appreciation that mixed cultures are essential for the eventual properties of the manufactured cheese the vast majority of studies on L. lactis were carried out in laboratory media with a pure culture. In this study we applied an advanced recombinant in vivo expression technology (R-IVET) assay in combination with a high-throughput cheese-manufacturing protocol for the identification and subsequent validation of promoter sequences specifically induced during the manufacturing and ripening of cheese. The system allowed gene expression measurements in an undisturbed product environment without the use of antibiotics and in combination with a mixed strain starter culture. The utilization of bacterial luciferase as reporter enabled the real-time monitoring of gene expression in cheese for up to 200 h after the cheese-manufacturing process was initiated. The results revealed a number of genes that were clearly induced in cheese such as cysD, bcaP, dppA, hisC, gltA, rpsE, purL, amtB as well as a number of hypothetical genes, pseudogenes and notably genetic elements located on the non-coding strand of annotated open reading frames. Furthermore genes that are likely to be involved in interactions with bacteria used in the mixed strain starter culture were identified.

  3. Identification and functional characterisation of cellobiose and lactose transport systems in Lactococcus lactis IL1403.

    Science.gov (United States)

    Kowalczyk, Magdalena; Cocaign-Bousquet, Muriel; Loubiere, Pascal; Bardowski, Jacek

    2008-03-01

    Physiological, biochemical and macroarray analyses of Lactococcus lactis IL1403 and its ccpA and bglR single and double mutants engaged in lactose and beta-glucosides catabolism were performed. The kinetic analysis indicated the presence of different transport systems for salicin and cellobiose. The control of salicin catabolism was found to be mediated by the transcriptional regulator BglR and the CcpA protein. The transcriptional analysis by macroarray technology of genes from the PEP:PTS regions showed that several genes, like ybhE, celB, ptcB and ptcA, were expressed at higher levels both in wild type cells exposed to cellobiose and in the ccpA mutant. We also demonstrated that in L. lactis IL1403 cultured on medium with cellobiose and lactose as carbon sources, after the first phase of cellobiose consumption and then co-metabolism of the two sugars, when cellobiose is exhausted the strain uses lactose as the only carbon source. These data could indicate that lactose and cellobiose are transported by a unique system-a PTS carrier induced by the presence of cellobiose, and negatively controlled by the CcpA regulator.

  4. Lactococcus lactis LMG2081 Produces Two Bacteriocins, a Nonlantibiotic and a Novel Lantibiotic.

    Science.gov (United States)

    Mirkovic, Nemanja; Polovic, Natalija; Vukotic, Goran; Jovcic, Branko; Miljkovic, Marija; Radulovic, Zorica; Diep, Dzung B; Kojic, Milan

    2016-04-01

    Bacteriocin producers normally possess dedicated immunity systems to protect themselves from their own bacteriocins.Lactococcus lactis strains LMG2081 and BGBM50 are known as lactococcin G producers. However, BGBM50 was sensitive to LMG2081, which indicated that LMG2081 might produce additional bacteriocins that are not present in BGBM50. Therefore, whole-genome sequencing of the two strains was performed, and a lantibiotic operon (called lctLMG) was identified in LMG2081 but not in BGBM50. The lctLMG operon contains six open reading frames; the first three genes,lmgA ,lmgM, and lmgT, are involved in the biosynthesis and export of bacteriocin, while the other three genes,lmgF,lmgE, and lmgG, are involved in lantibiotic immunity. Mutational analysis confirmed that the lctLMG operon is responsible for the additional antimicrobial activity. Specifically, site-directed mutation within this operon rendered LMG2081 inactive toward BGBM50. Subsequent purification and electrospray ionization-time of flight mass spectrometric analysis confirmed that the lantibiotic bacteriocin called lacticin LMG is exported as a 25-amino-acid peptide. Lacticin LMG is highly similar to the lacticin 481 group. It is interesting that a bacteriocin producer produces two different classes of bacteriocins, whose operons are located in the chromosome and a plasmid.

  5. [Characteristics and identification of bacteriocins produced by Lactococcus lactis subsp. lactis 194-K].

    Science.gov (United States)

    Ustiugova, E A; Timofeeva, A V; Stoianova, L G; Netrusov, A I; Katrukha, G S

    2012-01-01

    The Lactococcus lactis subsp. lactis 194-K strain has been established to be able to produce two bacteriocins, one of which was identified as the known lantibiotic nisin A, and the other 194-D bacteriocin represents a polypeptide with a 2589-Da molecular mass and comprises 20 amino acid residues. Both bacteriocins were produced in varying proportions in all of the studied nutrient media, which support the growth of the producer. Depending on the cultivation medium, the nisin A content was 380- to 1123-fold lower in the 194-K stain culture fluid than that of the 194-D peptide. In comparision to to nisin A Bacteriocin 194-D possessed a wide range of antibacterial activity and suppressed the growth of both Gram-positive and Gram-negative bacteria. An optimal medium for 194-D bacteriocin synthesis was shown to be a fermentation medium which contained yeast extract, casein hydrolysate, and potassium phosphate. The biosynthesis ofbacteriocin 194-D by the 194-K strain in these media occurred parallel to producer growth, and its maximal accumulation in the culture fluid was observed at 14-20 h of the strain's growth.

  6. Transcriptome and proteome exploration to model translation efficiency and protein stability in Lactococcus lactis.

    Directory of Open Access Journals (Sweden)

    Clémentine Dressaire

    2009-12-01

    Full Text Available This genome-scale study analysed the various parameters influencing protein levels in cells. To achieve this goal, the model bacterium Lactococcus lactis was grown at steady state in continuous cultures at different growth rates, and proteomic and transcriptomic data were thoroughly compared. Ratios of mRNA to protein were highly variable among proteins but also, for a given gene, between the different growth conditions. The modeling of cellular processes combined with a data fitting modeling approach allowed both translation efficiencies and degradation rates to be estimated for each protein in each growth condition. Estimated translational efficiencies and degradation rates strongly differed between proteins and were tested for their biological significance through statistical correlations with relevant parameters such as codon or amino acid bias. These efficiencies and degradation rates were not constant in all growth conditions and were inversely proportional to the growth rate, indicating a more efficient translation at low growth rate but an antagonistic higher rate of protein degradation. Estimated protein median half-lives ranged from 23 to 224 min, underlying the importance of protein degradation notably at low growth rates. The regulation of intracellular protein level was analysed through regulatory coefficient calculations, revealing a complex control depending on protein and growth conditions. The modeling approach enabled translational efficiencies and protein degradation rates to be estimated, two biological parameters extremely difficult to determine experimentally and generally lacking in bacteria. This method is generic and can now be extended to other environments and/or other micro-organisms.

  7. Antigenicity and Immunogenicity of Rotavirus VP6 Protein Expressed on the Surface of Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    L. E. Esteban

    2013-01-01

    Full Text Available Group A rotaviruses are the major etiologic agents of acute gastroenteritis worldwide in children and young animals. Among its structural proteins, VP6 is the most immunogenic and is highly conserved within this group. Lactococcus lactis is a food-grade, Gram-positive, and nonpathogenic lactic acid bacteria that has already been explored as a mucosal delivery system of heterologous antigens. In this work, the nisin-controlled expression system was used to display the VP6 protein at the cell surface of L. lactis. Conditions for optimal gene expression were established by testing different nisin concentrations, cell density at induction, and incubation times after induction. Cytoplasmic and cell wall protein extracts were analyzed by Western blot and surface expression was confirmed by flow cytometry. Both analysis provided evidence that VP6 was efficiently expressed and displayed on the cell surface of L. lactis. Furthermore, the humoral response of mice immunized with recombinant L. lactis was evaluated and the displayed recombinant VP6 protein proved to be immunogenic. In conclusion, this is the first report of displaying VP6 protein on the surface of L. lactis to induce a specific immune response against rotavirus. These results provide the basis for further evaluation of this VP6-displaying L. lactis as a mucosal delivery vector in a mouse model of rotavirus infection.

  8. Systematic identification of tRNAome and its dynamics in Lactococcus lactis

    Science.gov (United States)

    Puri, Pranav; Wetzel, Collin; Saffert, Paul; W.Gaston, Kirk; Russell, Susan P.; Varela, Juan A. Cordero; van der Vlies, Pieter; Zhang, Gong; Limbach, Patrick A.; Ignatova, Zoya; Poolman, Bert

    2014-01-01

    Transfer RNAs (tRNA) through their abundance and modification pattern significantly influence protein translation. Here, we present a systematic analysis of the tRNAome of Lactococcus lactis. Using the next-generation sequencing approach, we identified 40 tRNAs which carry 16 different posttranscriptional modifications as revealed by mass spectrometry analysis. While small modifications are located in the tRNA body, hypermodified nucleotides are mainly present in the anticodon loop, which through wobbling expand the decoding potential of the tRNAs. Using tRNA-based microarrays, we also determined the dynamics in tRNA abundance upon changes in the growth rate and heterologous protein overexpression stress. With a four-fold increase in the growth rate, the relative abundance of tRNAs cognate to low abundance codons decrease, while the tRNAs cognate to major codons remain mostly unchanged. Significant changes in the tRNA abundances are observed upon protein overexpression stress, which does not correlate with the codon usage of the overexpressed gene but rather reflects the altered expression of housekeeping genes. PMID:25040919

  9. ClpE from Lactococcus lactis promotes repression of CtsR-dependent gene expression

    DEFF Research Database (Denmark)

    Varmanen, P.; Vogensen, F.K.; Hammer, Karin;

    2003-01-01

    The heat shock response in bacterial cells is characterized by rapid induction of heat shock protein expression, followed by an adaptation period during which heat shock protein synthesis decreases to a new steady-state level. In this study we found that after a shift to a high temperature the Clp...... ATPase (ClpE) in Lactococcus lactis is required for such a decrease in expression of a gene negatively regulated by the heat shock regulator (CtsR). Northern blot analysis showed that while a shift to a high temperature in wild-type cells resulted in a temporal increase followed by a decrease......E by Western blot analysis revealed that at a high temperature CIpE is subjected to ClpP-dependent processing and that disruption of the zinc finger domain renders GpE more susceptible. Interestingly, this domain resembles the N-terminal region of McsA, which was recently reported to interact with the Cts...

  10. Meningencefalite por Pasteurella multocida: estudo clínico-laboratorial de um caso em lactente

    Directory of Open Access Journals (Sweden)

    C. E. Levy

    1989-12-01

    Full Text Available Os autores apresentam descrição clínico-laboratorial e evolutiva do caso de lactente com o diagnóstico de meningencefalite por Pasteurella multocida que apresentou na evolução atraso neuromotor, manifestações epilépticas, surdez neurossensorial e paresia crural à esquerda. Fazem também breve revisão do papel deste agente etiológico na patologia humana. Ressaltam a importância da P. multocida em casos de meningites bacterianas, fazendo-se o diagnóstico laboratorial diferencial com o Haemophilus influenzae e Neisseria meningitidis em processos infecciosos conseqüentes a arranhadura ou mordida de animais e nas bacteremias ou septicemias em pacientes com hepatopatias crônicas ou em estados de imunodepressão.

  11. BIODEGRADACIÓN BACTERIANA DE PLAGUICIDAS PERMETRINA Y CIPERMETRINA EN CULTIVO LOTE

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    José C. Mendoza

    2011-01-01

    Full Text Available Fue estudiada la biodegradación de permetrina y cipermetrina a concentraciones de 50 y 100 mg/L, con cepas de Pseudomonas putida, Pseudomonas mendocina, Chromobacterium violaceum y Burkholderia cepacia, en reactores por lotes. Las cepas de Pseudomonas putida y Pseudomonas mendocina fueron las que presentaron una mayor capacidad de biodegradación de los plaguicidas, a partir de los 5 días esta es del 65% para ambos plaguicidas y después de los 15 días se mantiene prácticamente constante, siendo de hasta el 95% para permetrina a 50 y 100 mg/L y para cipermetrina del 90% a 50 mg/L y 89% a 100 mg/L medido mediante espectrofotometría UV/Vis. La cinética de crecimiento y los espectros de infrarrojo muestran que hay una mayor capacidad de mineralización para el plaguicida permetrina que para la cipermetrina. Estos resultados indican que estas bacterias pueden ser usadas en procesos de biorremediación de estos plaguicidas.

  12. Prognosis of bacterial meningitis in children Prognóstico de meningite bacteriana em crianças

    Directory of Open Access Journals (Sweden)

    Irenio Gomes

    1996-09-01

    Full Text Available We studied the incidence and prognosis of acute neurologic complications in 281 children under 13 years of age with a diagnosis of acute bacterial meningitis. All the patients were examined daily by the same group of neurologists, using a standardized neurological examination. Patients with signs of encephalic lesions, unsatisfactory response to antibiotics or decreased level of consciousness were submitted to brain computer tomography. The overall lethality rate was 20.3% and cases whose causative agent was identified presented a higher lethality rate (23.7% than those in which the agent was not found. The most important neurological abnormalities were meningeal signs (88.3% followed by decreased consciousness (47.7%, irritability (35.2%, seizures (22.4%, fontanel bulging (20.6% and cranial nerve palsy (14.2%. Seizures, cranial nerve palsy and the absence of meningeal signs were related to higher rates of lethality. Diminished consciousness, seizures, subdural effusion, abscess and hydrocephalus were the most important complications, respectively. We can conclude that acute bacterial meningitis continues to be an important health problem in developing countries and that public health measures will be necessary to minimize the impact of sequelae and reduce the mortality rate in children with that pathology.Para estudar os fatores prognósticos e incidência de complicações em meningite bacteriana, 281 crianças (idade abaixo de 13 anos com quadro clínico e do LCR compatíveis com esse diagnóstico foram acompanhadas, durante o internamente, através de ficha de avaliação padrão. Aquelas que apresentaram sinais de lesão encefálica, resposta inadequada ao tratamento ou diminuição do nível de consciência, com Glasgow < 7, foram submetidas a tomografia computadorizada de crânio. A taxa de letalidade global foi 20,3%, sendo maior quando o agente etiológico foi identificado (23,7%. As alterações neurológicas mais encontradas foram

  13. Contaminación bacteriana en concentrados de plaquetas de caballos Bacterial contamination in platelet concentrates of horses

    Directory of Open Access Journals (Sweden)

    ME Álvarez

    2010-01-01

    Full Text Available Los objetivos del estudio fueron: 1 evaluar el riesgo de contaminación bacteriana de concentrados autólogos de plaquetas (APCs de caballos obtenidos mediante el método del tubo en tres condiciones técnicas diferentes (cámara de flujo laminar y en ambiente de laboratorio limpio con mechero o sin mechero, 2 identificar los puntos críticos del proceso de preparación de los APCs con posibilidad de contaminación bacteriana y 3 identificar las bacterias potencialmente contaminantes en el proceso. Se tomaron muestras bacteriológicas de la piel (rasurada o no del sitio de venopunción de 15 caballos, antes y después de ser desinfectados; manos y garganta del operario; tapones de los tubos donde se procesó la sangre; medio ambiente donde se tomaron las muestras de sangre, ambiente de laboratorio, cámara de flujo laminar, estufa bacteriológica y de los APCs obtenidos bajo condiciones técnicas. Se aislaron bacterias de la piel equina sin desinfectar, manos y garganta del operario y del lugar donde se tomaron las muestras de sangre. No se aislaron bacterias de los tapones de los tubos, medio ambiente del laboratorio, cámara de flujo laminar, ni de los APCs. Las bacterias aisladas fueron biota normal de la piel equina, de la piel y garganta humana, y contaminantes medioambientales. En conclusión, los APCs pueden ser obtenidos mediante el método del tubo en un ambiente limpio.The aims of the study were to: 1 assess the risk of bacterial contamination in equine platelet concentrates (PCs obtained by the tube method under three technical conditions (laminar flow cabinet or in a clean laboratory environment both with burner and without burner 2 identify the critical points of the process of PCs preparation with risk of bacterial contamination; and 3 identify the potential bacterial contaminants in the process. Bacteriological samples were taken from the skin (shaved or unshaved of the venipuncture site in 15 horses, both before and after being

  14. Síntesis intratecal de C3c e inmunoglobulinas en niños con meningoencefalitis bacteriana

    Directory of Open Access Journals (Sweden)

    Bárbara Padilla-Docal

    2008-12-01

    Full Text Available Las meningoencefalitis bacterianas constituyen una fuente importante de morbilidad, mortalidad y discapacidad en diferentes regiones del mundo. El objetivo del presente trabajo es conocer si el sistema de complemento puede estar involucrado en la lisis de las bacterias productoras de meningoencefalitis a través de la liberación de C3c al líquido cefalorraquídeo. Se estudiaron siete pacientes con edad promedio de 3 años, que ingresaron en el Hospital Pediátrico de San Miguel del Padrón, a los que se les realizó una punción lumbar diagnóstica y se les aislaron los gérmenes siguientes: Neisseria meningitidis, Streptococcus pneumoniae y Haemophilus influenzae. La cuantificación de los niveles de C3c, albúmina e inmunoglobulinas mayores en suero y líquido cefalorraquídeo se realizó en placas de inmunodifusión radial. Los resultados obtenidos fueron recogidos en un reibergrama. El total de los pacientes estudiados mostraron síntesis intratecal del componente C3c del sistema de complemento. Este hecho evidenció la activación de este sistema en alguna de sus vías y que una vez cumplidas sus funciones biológicas, ha sufrido un proceso de degradación y liberación al LCR en forma de C3c.

  15. Amigdalitis aguda recurrente bacteriana: Estudio prospectivo, comparativo y controlado de sus características clínicas y microbiológicas

    OpenAIRE

    Der M,Carolina; Iñiguez C,Rodrigo; Guzman D,Ana Maria; Jofré P,David; Iñiguez C,Armando; Labarca L,Jaime

    2007-01-01

    Introducción: La amigdalitis aguda recurrente es una patología de frecuente consulta, es una de las indicaciones de amigdalectomía. No se sabe con exactitud el origen de esta patología. Objetivo: Identificar la microbiología y patrones de susceptibilidad de las bacterias en la amigdalitis aguda recurrente bacteriana (AARB) a los antimicrobianos más comúnmente en el medio nacional, usados en su tratamiento. Material y método: Se planificó un estudio prospectivo, controlado y ciego. Se evaluaro...

  16. Tireoidite bacteriana supurativa: relato de caso e revisão da literatura Acute suppurative thyroiditis: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Adriana Vieira Pedreira

    2002-11-01

    Full Text Available Neste trabalho é apresentado um caso de tireoidite bacteriana aguda em um criança lúpica de nove anos de idade, em que o diagnóstico precoce foi imprescindível pela gravidade do quadro. Em seguida é apresentada uma revisão da literatura sobre o assunto.We present the case of a 9-year-old girl with acute suppurative thyroiditis and systemic lupus erythematosus. Early diagnosis was crucial for the outcome of the patient due to the severity of the disease. A review of the literature is also presented.

  17. Caracterización de pacientes con bronconeumonía bacteriana asociada a la ventilación artificial mecánica

    OpenAIRE

    Danilo Eranio Utra Cardoso; Leonila Atencio González; Aida Esther Leyva Peña; Gladis Marrero Ávila; Idalia Arcias Castillo

    2015-01-01

    Fundamento: las neumonías nosocomiales constituyen hoy en día un problema de salud a nivel mundial. En las unidades de cuidados intensivos de las instituciones hospitalarias ingresa un elevado número de pacientes que requieren ventilación artificial mecánica, factor de riesgo asociado a este tipo de infecciones. Objetivo: caracterizar a los pacientes con neumonías bacterianas asociadas a la ventilación artificial mecánica, ingresados en la sala de cuidados intensivos del Hospital General D...

  18. Acumulación de antibióticos y su efecto sobre la comunidad bacteriana presentes en sedimentos de piscinas camaroneras

    OpenAIRE

    Uyaguari, Miguel; Montoya, Nelson

    2002-01-01

    Acumulación de antibióticos y su efecto sobre la comunidad bacteriana presentes en sedimentos de piscinas camaroneras La proliferación de enfermedades ha sido uno de los grandes retos con los que ha tenido que lidiar el sector camaronero. Las medidas profilácticas son lo más importante para prevenir el brote de enfermedades, sin embargo cuando el brote se manifiesta, la medicación es necesaria para evitar las altas mortalidades.

  19. Simulação, desenvolvimento de equipamento e validação experimental de ensaios não destrutivos com células bacterianas

    OpenAIRE

    Costa, Alexandre Manuel Afonso

    2014-01-01

    A técnica de Ensaios Não Destrutivos (END) baseada em células bacterianas (CB) foi proposta recentemente e tem demonstrado viabilidade na identificação de micro defeitos superficiais, com espessuras e profundidades inferiores a 5 μm, em vários materiais de engenharia. O conhecimento processual já é significativo, mas diversos aspectos carecem de desenvolvimentos, nomeadamente, a interacção das bactérias com outros materiais, o limiar de detectabilidade da técnica, a aplicação a defeitos na...

  20. Estrategia para la mejora de la degradación del ácido p-cumárico mediante selección bacteriana

    OpenAIRE

    Otal, E.; Arnáiz Franco, Carmen; Gutiérrez, J.C.; Lebrato Martínez, Julián

    2003-01-01

    Artículo original escaneado para el Repositorio (archivo delegado) Recientemente está recibiendo gran aceptación el tratamiento integrado quimicobiológico de aguas residuales que contienen compuestos orgánicos defícilmente biodegradables. Sim embargo, estudios realizados con aguas sintéticas con ácido p-cumárico mostraron que el tratamiento químico previo al tratamiento biológico no mejoraba su degradación. En este trabajo se han aislado e identificado estirpes bacterianas capaces de crece...

  1. Genética y genómica enfocadas en el estudio de la resistencia bacteriana Genetics and Genomics for the study of bacterial resistance

    OpenAIRE

    Ulises Garza-Ramos; Jesús Silva-Sánchez; Esperanza Martínez-Romero

    2009-01-01

    La resistencia bacteriana es un problema de salud pública causante de índices elevados de morbi-mortalidad hospitalaria. En la medida en que se usan los diferentes antibióticos se seleccionan bacterias resistentes a múltiples fármacos. El desarrollo de nuevas herramientas moleculares de la genómica y proteómica, como el PCR en tiempo real, pirosecuenciación de ADN, espectrometría de masas, microarreglos de ADN y bioinformática, permite conocer en forma más estrecha la fisiología y estructura ...

  2. Efecto de las condiciones de cultivo y purificación sobre las propiedades fisicoquímicas y de transporte en membranas de celulosa bacteriana

    OpenAIRE

    Carreño Pineda, Luz Dary

    2011-01-01

    En el presente trabajo fueron sintetizadas membranas de celulosa bacteriana a partir de un aislado nativo de Acetobacter xylinum. Se variaron como condiciones de cultivo la temperatura y la fuente de carbono, y como condiciones de purificación el agente purificante, la temperatura y el tiempo de exposición, y se evaluó el efecto de estas condiciones sobre las propiedades fisicoquímicas y de transporte de las membranas. Se caracterizaron con pruebas de difracción de rayos X, calorimetría di...

  3. Molecular biology applied to the laboratory diagnosis of bacterial endophthalmitis Biologia molecular aplicada ao diagnóstico laboratorial de endoftalmite bacteriana

    Directory of Open Access Journals (Sweden)

    Paulo José Martins Bispo

    2009-10-01

    Full Text Available Bacterial endophthalmitis is a serious but uncommon intraocular infection which frequently results in vision loss. Early diagnosis and appropriate therapy are associated with better visual outcome. Conventional microbiological methods are currently used for microbiological characterization of eyes with suspected endophthalmitis. However, the sensitivity of bacterial detection from aqueous and vitreous humor using microbiology techniques is poor, and time-consuming to confirm the results. The application of molecular methods enhances significantly laboratory confirmation of bacterial endophthalmitis, demanding a shorter time to draw a definitive result and thereby promoting the early initiation of a more specific therapy to limit the empirical or unnecessary use of broad-spectrum antibiotics. PCR-based techniques, including post-PCR methods such RFLP, DNA probe hybridization and DNA sequencing have been successfully used for the diagnostic elucidation of clinically suspected bacterial endophthalmitis cases, showing promising application in the routine practice of ocular microbiology laboratories.Endoftalmite bacteriana é uma infecção intraocular grave, mas de baixa frequência, podendo resultar em grande prejuízo visual. O diagnóstico precoce e a rápida instituição de terapia adequada estão associadas a um melhor prognóstico da doença. Os métodos microbiológicos convencionais são utilizados rotineiramente para caracterização microbiológica de olhos com suspeita de endoftalmite. No entanto, a sensibilidade de detecção bacteriana em amostras de humor aquoso e vítreo utilizando técnicas microbiológicas é baixa, além de demandar um maior tempo para a confirmação dos resultados. A utilização de métodos moleculares aumenta significativamente os casos de endoftalmite bacteriana confirmados laboratorialmente, com tempo menor para a liberação de um resultado definitivo, auxiliando assim a instituição precoce de uma terapia

  4. Resina acrílica: relação entre tratamento superficial e retenção de placa bacteriana

    OpenAIRE

    Rego, Marina R. M.; Kitahara, Flávia M. F.; SANTIAGO,Luiz Carlos

    2010-01-01

    Este estudo avaliou a influência de técnicas de tratamento superficial da resina acrílica na adesão de placa bacteriana utilizando microbiota encontrado na cavidade bucal. Foram confeccionados noventa corpos de prova cilíndricos em resina acrílica autopolimerizável e divididos em nove grupos, para utilização de várias técnicas de tratamento superfi¬cial usualmente utilizadas nesse material. Os corpos-de-prova fora...

  5. Cerclaje profiláctico en mujeres con nacimientos prematuros espontáneos previos, asociados con infección bacteriana ascendente

    OpenAIRE

    Ovalle S,Alfredo; Valderrama C,Oscar; Rencoret P,Gustavo; Fuentes G,Ariel; del Río V,María José; Kakarieka W,Elena; Martínez T,María Angélica; Pizarro S,Dagoberto

    2012-01-01

    Objetivo: Determinar la eficacia del cerclaje cervical profiláctico en pacientes con embarazos únicos, cérvix >25 mm e historia de nacimientos prematuros espontáneos, asociados con infección bacteriana ascendente (IBA). Métodos: Estudio clínico en pacientes con embarazos únicos y partos prematuros y/o abortos de 2° trimestre espontáneos previos, sin partos de término, asociados con IBA. Se incluyeron los casos con longitud cervical de >25 mm al ingreso. Se comparó el cerclaje cervical h...

  6. Estratégias para prevenção da resistência bacteriana: contribuições para a segurança do paciente

    OpenAIRE

    Roberta Soldatelli Pagno Paim; Elisiane Lorenzini

    2014-01-01

    Introdução: A resistência bacteriana tem como consequências, o aumento da morbidade, mortalidade e da internação hospitalar, o prolongamento das doenças, a perda da produtividade, o aumento dos custos e maior risco de complicações. Materiais e Métodos: Trata-se de um estudo descritivo, com abordagem qualitativa, na perspectiva de uma revisão integrativa da literatura, realizada em janeiro de 2014. Resultados e Discussão: Foram selecionados oito artigos que relatavam estratégias de prevenção d...

  7. Estratégias para prevenção da resistência bacteriana: contribuições para a segurança do paciente

    Directory of Open Access Journals (Sweden)

    Roberta Soldatelli Pagno Paim

    2014-11-01

    Full Text Available Introdução: A resistência bacteriana tem como consequências, o aumento da morbidade, mortalidade e da internação hospitalar, o prolongamento das doenças, a perda da produtividade, o aumento dos custos e maior risco de complicações. Materiais e Métodos: Trata-se de um estudo descritivo, com abordagem qualitativa, na perspectiva de uma revisão integrativa da literatura, realizada em janeiro de 2014. Resultados e Discussão: Foram selecionados oito artigos que relatavam estratégias de prevenção da resistência bacteriana em um recorte temporal de 2008 a 2014. O uso racional de antimicrobianos, a higienização adequada das mãos, a cultura de vigilância microbiológica, a educação continuada, a desinfecção de superfícies, uso de testes de suscetibilidade, o isolamento de contato, quando indicado e a manutenção de um banco de dados, são alguns dos métodos encontrados neste trabalho para prevenir a seleção de micro-organismos resistentes. Conclusões: A diminuição do lançamento de novos antimicrobianos pela indústria farmacêutica e a necessidade de novos antibióticos reforça ainda mais a importância da conscientização de toda a equipe multidisciplinar no processo de prevenção de resistência antimicrobiana.            Palavras chave: Farmacorresistência Bacteriana, Antibacterianos, Programa de Controle de Infecção Hospitalar, Infecção Hospitalar, Segurança do Paciente. (Fonte: DeCS BIREME.Cómo citar este artículo: Paim R, Lorenzini E. Estrategias para prevenção da resistência bacteriana. Rev Cuid. 2014; 5(2:757-64. http://dx.doi.org/10.15649/cuidarte.v5i2.88

  8. Isolation and identification of Lactococcus lactis and Weissella%乳酸乳球菌和魏斯氏菌的分离及鉴定

    Institute of Scientific and Technical Information of China (English)

    商婷婷; 张日俊

    2013-01-01

    This experiment was conducted to isolate and identify Lactococcus lactis and Weissel-la. According to the morphological character and microscopic examination, six lactic acid coc-cus strains were isolated and identified from samples of raw milk, pickle, silage and commercial cheese. By physiological and biochemical reaction, salt tolerance and heat resistance reaction and 16S rDNA sequence analysis, four strains belong to Lactococcus lactis, ST2 is lactococcus lactis subsp. Cremoris and ST7 is Lactococcus lactis subsp. Lactis; two strains were identified as Weissella, one of them is Weissella cibaria. These results indicated that raw milk and pickle are the excellent habitats of Lactococcus lactis and Weissella correspondingly, with the incorpo-ration of traditional methods and molecular biology techniques, strains could be isolated and identified more accurately and rapidly.%试验以生牛奶、自制泡菜水、青贮料、市售奶酪为样品,进行乳酸乳球菌和魏斯氏菌的筛选与鉴定。通过培养基中菌落形态观察和镜检细胞形态观察,共筛得6株疑似乳酸球菌(分别命名为ST1、ST2、ST6、ST7、ST8、ST9)。经生理生化、耐盐性、耐热性试验以及16S rD-NA序列分析鉴定,这6株菌分属两个属:ST1、ST2、ST7、ST9为乳酸乳球菌(Lactococcus lac-tis),其中ST2为乳酸乳球菌乳脂亚种(Lactococcus lactis subsp. Cremoris),ST7为乳酸乳球菌乳酸亚种(Lactococcus lactis subsp. Lactis );ST6、ST8属于魏斯氏菌属(Weissella),其中ST6为食窦魏斯氏菌(Weissella cibaria)。研究表明,生牛奶和泡菜水分别是乳酸乳球菌和魏斯氏菌的优良生活环境,传统方法与分子生物技术相结合可更准确快速地分离及鉴定菌株。

  9. Análise microbiológica da placa bacteriana da doença periodontal em cães e o efeito da antibioticoterapia sobre ela

    OpenAIRE

    Fonseca, Stella Alves da; Galera,Paula Diniz; Brito, Daiana Lima; Perecmanis,Simone; Silva,Anahí Souza; Cardoso, Larissa Borges; Marçola,Tatiana Guerrero; Drummond,Vinícius Oliveira; Pimentel,Concepta McManus

    2011-01-01

    Objetivou-se determinar a microbiota da placa bacteriana subgengival de cães com doença periodontal (DP) e estabelecer o efeito da antibioticoterapia. Avaliaram-se 20 cães com graus variados de DP e coletaram-se amostras da placa bacteriana subgengival antes e após antibioticoterapia. Preconizou-se antibioticoterapia distinta em dois grupos, com 10 animais cada: clindamicina (G1) e metronidazol + espiramicina (G2). Observou-se crescimento bacteriano subgengival na maioria dos cães com DP e co...

  10. Expression of Helicobacter pylori hspA Gene in Lactococcus lactis NICE System and Experimental Study on Its Immunoreactivity

    OpenAIRE

    Xiao-Juan Zhang; Shu-Ying Feng; Zhi-Tao Li; Yan-Ming Feng

    2015-01-01

    Aim. The aim of this study was to develop an oral Lactococcus lactis (L. lactis) vaccine against Helicobacter pylori (H. pylori). Methods. After L. lactis NZ3900/pNZ8110-hspA was constructed, growth curves were plotted to study whether the growth of recombinant L. lactis was affected after hspA was cloned into L. lactis and whether the growth of empty bacteria, empty plasmid bacteria, and recombinant L. lactis was affected by different concentrations of Nisin; SDS-PAGE and Western blot were a...

  11. Draft Genome Sequence of Lactococcus lactis subsp. lactis bv. diacetylactis CRL264, a Citrate-Fermenting Strain

    Science.gov (United States)

    Zuljan, Federico; Espariz, Martín; Blancato, Victor S.; Esteban, Luis; Alarcón, Sergio

    2016-01-01

    We report the draft genome sequence of Lactococcus lactis subsp. lactis bv. diacetylactis CRL264, a natural strain isolated from artisanal cheese from northwest Argentina. L. lactis subsp. lactis bv. diacetylactis is one of the most important microorganisms used as starter culture around the world. The CRL264 strain constitutes a model microorganism in the studies on the generation of aroma compounds (diacetyl, acetoin, and 2,3-butanediol) by lactic acid bacteria. Our genome analysis shows similar genetic organization to other available genomes of L. lactis bv. diacetylactis strains. PMID:26847906

  12. Influence of Stress Treatments on the Resistance of Lactococcus lactis to Freezing and Freeze-Drying

    OpenAIRE

    Lin, Chan

    1998-01-01

    This study investigated the effect of cold, heat, or osmotic shock treatment on the resistance of L. lactis subsp. cremoris MM160 and MM310 and Lactococcus lactis subsp. lactis MM210 and FG2 cheese starter bacteria to freezing and freeze-drying. The ability to withstand freezing at -60°C for 24 h was variable among lactococci, but resistance to this treatment was significantly improved (P < 0.05) in most strains by a 2-h cold shock at l0°C or a 25-min heat shock at 39°C (L. lactis subsp. crem...

  13. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: evaluation of the probiotic potential.

    Science.gov (United States)

    Furtado, Danielle N; Todorov, Svetoslav D; Landgraf, Mariza; Destro, Maria T; Franco, Bernadette D G M

    2014-01-01

    Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its probiotic potential. Lc. lactis DF4Mi was resistant to acidic pH and oxbile, presented co-aggregation with Listeria monocytogenes, and was not affected by several drugs from different generic groups, being sensitive to most tested antibiotics. These properties indicate that this Lc. lactis strain can be used for enhancement of dairy foods safety and quality, in combination with potential probiotic properties.

  14. Cloning and verification of the Lactococcus lactis pyrG gene and characterization of the gene product, CTP synthase

    DEFF Research Database (Denmark)

    Wadskov-Hansen, Steen Lyders Lerche; Willemoës, M.; Martinussen, Jan

    2001-01-01

    The pyrG gene of Lactococcus lactis subsp. cremoris, encoding CTP synthase, has been cloned and sequenced. It is flanked upstream by an open reading frame showing homology to several aminotransferases and downstream by an open reading frame of unknown function. L. lactis strains harboring disrupted...... of a functional cdd gene encoding cytidine deaminase. A characterization of the enzyme revealed similar properties as found for CTP synthases from other organisms. However, unlike the majority of CTP synthases the lactococcal enzyme can convert dUTP to dCTP, although a half saturation concentration of 0.6 m...

  15. Bacteriocinogenic Lactococcus lactis subsp: lactis DF04Mi isolated from goat milk: Evaluation of the probiotic potential

    Directory of Open Access Journals (Sweden)

    Danielle N. Furtado

    2014-09-01

    Full Text Available Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi was isolated from goat milk, and studied for its probiotic potential. Lc. lactis DF4Mi was resistant to acidic pH and oxbile, presented co-aggregation with Listeria monocytogenes, and was not affected by several drugs from different generic groups, being sensitive to most tested antibiotics. These properties indicate that this Lc. lactis strain can be used for enhancement of dairy foods safety and quality, in combination with potential probiotic properties.

  16. Glucose metabolism in Lactococcus lactis MG1363 under different aeration conditions: Requirement of acetate to sustain growth under microaerobic conditions

    DEFF Research Database (Denmark)

    Nordkvist, Mikkel; Jensen, N.B.S.; Villadsen, John

    2003-01-01

    Lactococcus lactis subsp. lactis MG1363 was grown in batch cultures on a defined medium with glucose as the energy source under different aeration conditions, namely, anaerobic conditions, aerobic conditions, and microaerobic conditions with a dissolved oxygen tension of 5% (when saturation...... with air was used as the reference). The maximum specific growth rate was high (0.78 to 0.91 h(-1)) under all aeration conditions but decreased with increasing aeration, and more than 90% of the glucose was converted to lactate. However, a shift in by-product formation was observed. Increasing aeration...

  17. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO Molecular Identification Of Bacterial Populations Associated To Queen Conch (Strombus gigas From Colombian Caribbe

    Directory of Open Access Journals (Sweden)

    EDINSON ANDRÉS ACOSTA

    Full Text Available El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y socioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como "vulnerable" y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 10(6 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >10(5 ufc mL-1. El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.The Queen Conch, Strombus gigas (Strombidae, is a species of great ecological and socioeconomic importance in the Caribbean area of Colombia. However, it is currently catalogued as "vulnerable"; there is limited information concerning the bacterial species associated with conch and important in the

  18. Protocolo de actuación forense ante la sospecha de meningitis bacteriana y shock séptico fulminante Protocol for the forensic action with regard to the suspicion of bacterial meningitis and fulminant septicemia

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    A. Fernández-Rodríguez

    2004-07-01

    Full Text Available Una importante tarea de las instituciones médico-legales es la colaboración con las autoridades sanitarias en la prevención de riesgos para la salud pública. Uno de ellos es la infección meningocócica, que puede cursar rápidamente y con evolución fatal, causando muerte súbita. Neisseria meningitidis es la principal causa de meningitis bacteriana y septicemia en niños y adultos jóvenes. Su temprana detección es de extrema urgencia, ya que permite el adecuado tratamiento de los contactos. El rápido desarrollo de estas infecciones imposibilita en ocasiones el diagnóstico antemortem, resultando imprescindible el diagnóstico forense. Aunque los hallazgos postmortem suelen ser los del síndrome de Waterhouse-Friderichsen, estos, a veces, pueden pasar desapercibidos, o estar causados por otras bacterias. Todo ello hace necesario un diagnóstico microbiológico forense. Este artículo presenta un protocolo forense de actuación ante la sospecha de meningitis bacteriana y shock séptico fulminante. La toma de muestras para microbiología debe ser aséptica e incluir sangre, suero, LCR, líquido pleural, tejidos en fresco y orina. Estas muestras pueden remitirse al Instituto Nacional de Toxicología y Ciencias Forenses, donde se realizarán análisis específicos, que incluyen un screening antigénico y un diagnóstico de confirmación mediante PCR a tiempo real que identifica meningococo y su serogrupo. Los resultados de estas técnicas son informados 3 horas tras el inicio del análisis. También se realiza el cultivo bacteriano y PCR adicionales para detectar otras bacterias difíciles de aislar postmortem. La colaboración entre las distintas instituciones médico-legales y entre estas y las autoridades sanitarias es esencial para el adecuado manejo de estas graves infecciones.One of the main duties of medical-legal institutions is to collaborate with authorities to recognise and prevent risks to public health. One such risk is

  19. Lactococcus bacteriophages isolated from whey and their effects on commercial lactic starters

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    Maria Raquel de Godoy Oriani

    2004-08-01

    Full Text Available The incidence of phages of lactic acid bacteria in milk industry and their effects on acidification ability of commercial lactic acid starters were studied. Cheese whey samples (33 samples were collected from 17 factories. A total of 16 bacteriophages were isolated (12 specific for Lactococcus lactis, 3 for L. diacetylactis and one capable of lysing both species. The results showed that 10% reduction in acidification tests was not good indication of phage in the sample. The majority of samples showed reduction higher than 10%, although only 65% were phage positive. The isolated phages were quite stable and showed no reduction in infectivity even after 20 daily replications. A pool of bacteriophages was prepared from isolates and inoculated in 12 commercial lactic starters. After 8 hours of incubation, only 2 showed reduced acidification. Bacterial strains isolated from commercial starters were tested regarding the phage resistance. Considerable difference in phage sensitivity was observed among different starters (BD, D, O and L. diacetylactis. Five bacteriophages showed no infectivity on any isolates but one was infective for most of isolates.Para ampliar conhecimentos sobre a incidência de bacteriófagos de bactérias lácticas na indústria de leite do Estado de São Paulo e a sua influência sobre a capacidade acidificante de fermentos lácticos disponíveis em nosso mercado, o presente trabalho foi conduzido com o intuito de esclarecer a real situação dos laticínios no Estado. Foram coletadas 33 amostras de soro de queijo em 17 laticínios. Foram isolados 16 bacteriófagos, 12 específicos para Lactococcus lactis, 3 para L. diacetylactis e um capaz de lisar ambos os microrganismos. Os experimentos mostraram que, uma diminuição de 10% na acidez em presença de soro suspeito, ao contrário do estabelecido na literatura, não reflete a veracidade da presença de bacteriófagos na amostra, uma vez que a maioria apresentou redução acima

  20. Novos conhecimentos sobre a flora bacteriana vaginal Vaginal bacterial flora: up to date

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    Iara Moreno Linhares

    2010-01-01

    Full Text Available O objetivo desta revisão foi apresentar os novos conhecimentos sobre o ecossistema vaginal, enfatizando os métodos não cultiváveis de identificação microbiana (amplificação de genes, as várias espécies de Lactobacillus que podem compor a flora vaginal e a interação desta com os mecanismos locais de imunidade inata e adquirida, dependentes dos constituintes genéticos. Foram pesquisados no Medline (Pubmed os artigos relacionados ao tema publicados entre 1997 e 2009, selecionando-se apenas os considerados relevantes. A utilização de técnicas não cultiváveis (técnicas de amplificação de genes tem possibilitado o melhor conhecimento sobre a composição do ecossistema vaginal. Na maioria das mulheres no menacme predominam na vagina uma ou mais espécies de Lactobacillus: L. crispatus, . L. inners e L gasseri. Entretanto, em outras mulheres aparentemente saudáveis pode haver deficiência ou mesmo ausência de Lactobacillus, que são substituídos por outras bactérias produtoras de ácido lático: espécies de Atopobium, Megasphaera e/ou Leptotrichia. A infecção e/ou a proliferação de bactérias patogênicas na vagina são suprimidas pela produção de ácido lático, por produtos gerados pelas bactérias e pela atividade local das imunidades inata e adquirida. As células epiteliais vaginais produzem diversos componentes com atividade antimicrobiana. Tais células ainda possuem receptores de membrana ("Toll-like receptors" que reconhecem padrões moleculares associados aos patógenos. O reconhecimento leva à produção de citocinas proinflamatórias e à estimulação da imunidade antigenoespecífica. A produção de anticorpos IgG e IgA também pode ser iniciada na endocérvice e na vagina em resposta à infecção. Conclui-se que a composição da flora vaginal e os mecanismos de imunidade representam importantes mecanismos de defesa. Os critérios de "flora normal" e "flora anormal" devem ser revistos; os polimorfismos

  1. Lactococcus lactis metabolism and gene expression during growth on plant tissues.

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    Golomb, Benjamin L; Marco, Maria L

    2015-01-01

    Lactic acid bacteria have been isolated from living, harvested, and fermented plant materials; however, the adaptations these bacteria possess for growth on plant tissues are largely unknown. In this study, we investigated plant habitat-specific traits of Lactococcus lactis during growth in an Arabidopsis thaliana leaf tissue lysate (ATL). L. lactis KF147, a strain originally isolated from plants, exhibited a higher growth rate and reached 7.9-fold-greater cell densities during growth in ATL than the dairy-associated strain L. lactis IL1403. Transcriptome profiling (RNA-seq) of KF147 identified 853 induced and 264 repressed genes during growth in ATL compared to that in GM17 laboratory culture medium. Genes induced in ATL included those involved in the arginine deiminase pathway and a total of 140 carbohydrate transport and metabolism genes, many of which are involved in xylose, arabinose, cellobiose, and hemicellulose metabolism. The induction of those genes corresponded with L. lactis KF147 nutrient consumption and production of metabolic end products in ATL as measured by gas chromatography-time of flight mass spectrometry (GC-TOF/MS) untargeted metabolomic profiling. To assess the importance of specific plant-inducible genes for L. lactis growth in ATL, xylose metabolism was targeted for gene knockout mutagenesis. Wild-type L. lactis strain KF147 but not an xylA deletion mutant was able to grow using xylose as the sole carbon source. However, both strains grew to similarly high levels in ATL, indicating redundancy in L. lactis carbohydrate metabolism on plant tissues. These findings show that certain strains of L. lactis are well adapted for growth on plants and possess specific traits relevant for plant-based food, fuel, and feed fermentations.

  2. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine

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    Beatriz del Rio

    2016-03-01

    Full Text Available The dairy strain Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14 synthesizes the biogenic amine putrescine from agmatine via the agmatine deiminase (AGDI pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC, which encodes the proteins necessary for agmatine uptake and its conversion into putrescine [1,2]. The first gene of the cluster, aguR, encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC [2]. The catabolic operon aguBDAC is transcriptionally activated by agmatine [2] and transcriptionally regulated by carbon catabolite repression (CCR via glucose, but not by other sugars such as lactose or galactose [1,3]. On the contrary, the transcription of the aguR regulatory gene is not subject to CCR regulation [1,3] nor is regulated by agmatine [2]. In this study we report the transcriptional profiling of L. lactis subsp. cremoris CECT 8666 grown in M17 medium with galactose (GalM17 as carbon source and supplemented with agmatine, compared to that of the strain grown in the same culture medium without agmatine. The transcriptional profiling data of agmatine-regulated genes were deposited in the Gene Expression Omnibus (GEO database under Accession no. GSE74808.

  3. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine.

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    Del Rio, Beatriz; Redruello, Begoña; Martin, M Cruz; Fernandez, Maria; de Jong, Anne; Kuipers, Oscar P; Ladero, Victor; Alvarez, Miguel A

    2016-03-01

    The dairy strain Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14) synthesizes the biogenic amine putrescine from agmatine via the agmatine deiminase (AGDI) pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC, which encodes the proteins necessary for agmatine uptake and its conversion into putrescine [1], [2]. The first gene of the cluster, aguR, encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC[2]. The catabolic operon aguBDAC is transcriptionally activated by agmatine [2] and transcriptionally regulated by carbon catabolite repression (CCR) via glucose, but not by other sugars such as lactose or galactose [1], [3]. On the contrary, the transcription of the aguR regulatory gene is not subject to CCR regulation [1], [3] nor is regulated by agmatine [2]. In this study we report the transcriptional profiling of L. lactis subsp. cremoris CECT 8666 grown in M17 medium with galactose (GalM17) as carbon source and supplemented with agmatine, compared to that of the strain grown in the same culture medium without agmatine. The transcriptional profiling data of agmatine-regulated genes were deposited in the Gene Expression Omnibus (GEO) database under Accession no. GSE74808.

  4. Physiological function of the maltose operon regulator, MalR, in Lactococcus lactis

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    Rådström Peter

    2002-09-01

    Full Text Available Abstract Background Maltose metabolism is initiated by an ATP-dependent permease system in Lactococcus lactis. The subsequent degradation of intracellular maltose is performed by the concerted action of Pi-dependent maltose phosphorylase and β-phosphoglucomutase. In some Gram-positive bacteria, maltose metabolism is regulated by a maltose operon regulator (MalR, belonging to the LacI-GalR family of transcriptional regulators. A gene presumed to encode MalR has been found directly downstream the maltose phosphorylase-encoding gene, malP in L. lactis. The purpose of this study was to investigate the physiological role of the MalR protein in maltose metabolism in L. lactis. Results A L. lactis ssp. lactis mutant, TMB5004, deficient in the putative MalR protein, was physiologically characterised. The mutant was not able to ferment maltose, while its capability to grow on glucose as well as trehalose was not affected. The activity of maltose phosphorylase and β-phosphoglucomutase was not affected in the mutant. However, the specific maltose uptake rate in the wild type was, at its lowest, five times higher than in the mutant. This difference in maltose uptake increased as the maltose concentration in the assay was increased. Conclusion According to amino acid sequence similarities, the presumed MalR is a member of the LacI-GalR family of transcriptional regulators. Due to the suggested activating effect on maltose transport and absence of effect on the activities of maltose phosphorylase and β-phosphoglucomutase, MalR of L. lactis is considered rather as an activator than a repressor.

  5. PpiA, a surface PPIase of the cyclophilin family in Lactococcus lactis.

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    Nicolas Trémillon

    Full Text Available BACKGROUND: Protein folding in the envelope is a crucial limiting step of protein export and secretion. In order to better understand this process in Lactococcus lactis, a lactic acid bacterium, genes encoding putative exported folding factors like Peptidyl Prolyl Isomerases (PPIases were searched for in lactococcal genomes. RESULTS: In L. lactis, a new putative membrane PPIase of the cyclophilin subfamily, PpiA, was identified and characterized. ppiA gene was found to be constitutively expressed under normal and stress (heat shock, H(2O(2 conditions. Under normal conditions, PpiA protein was synthesized and released from intact cells by an exogenously added protease, showing that it was exposed at the cell surface. No obvious phenotype could be associated to a ppiA mutant strain under several laboratory conditions including stress conditions, except a very low sensitivity to H(2O(2. Induction of a ppiA copy provided in trans had no effect i on the thermosensitivity of an mutant strain deficient for the lactococcal surface protease HtrA and ii on the secretion and stability on four exported proteins (a highly degraded hybrid protein and three heterologous secreted proteins in an otherwise wild-type strain background. However, a recombinant soluble form of PpiA that had been produced and secreted in L. lactis and purified from a culture supernatant displayed both PPIase and chaperone activities. CONCLUSIONS: Although L. lactis PpiA, a protein produced and exposed at the cell surface under normal conditions, displayed a very moderate role in vivo, it was found, as a recombinant soluble form, to be endowed with folding activities in vitro.

  6. Cloning and expression of a novel lactococcal aggregation factor from Lactococcus lactis subsp. lactis BGKP1

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    Kojic Milan

    2011-12-01

    Full Text Available Abstract Background Aggregation may play a main role in the adhesion of bacteria to the gastrointestinal epithelium and their colonization ability, as well as in probiotic effects through co-aggregation with intestinal pathogens and their subsequent removal. The aggregation phenomenon in lactococci is directly associated with the sex factor and lactose plasmid co-integration event or duplication of the cell wall spanning (CWS domain of PrtP proteinase. Results Lactococcus lactis subsp. lactis BGKP1 was isolated from artisanal semi-hard homemade cheese and selected due to its strong auto-aggregation phenotype. Subsequently, non-aggregating derivative (Agg- of BGKP1, designated as BGKP1-20, was isolated, too. Comparative analysis of cell surface proteins of BGKP1 and derivative BGKP1-20 revealed a protein of approximately 200 kDa only in the parental strain BGKP1. The gene involved in aggregation (aggL was mapped on plasmid pKP1 (16.2 kb, cloned and expressed in homologous and heterologous lactococci and enterococci. This novel lactococcal aggregation protein was shown to be sufficient for cell aggregation in all tested hosts. In addition to the aggL gene, six more ORFs involved in replication (repB and repX, restriction and modification (hsdS, transposition (tnp and possible interaction with mucin (mbpL were also located on plasmid pKP1. Conclusion AggL is a new protein belonging to the collagen-binding superfamily of proteins and is sufficient for cell aggregation in lactococci.

  7. Optimization of the Lactococcus lactis nisin-controlled gene expression system NICE for industrial applications

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    Mond James

    2005-05-01

    Full Text Available Abstract Background The nisin-controlled gene expression system NICE of Lactococcus lactis is one of the most widely used expression systems in Gram-positive bacteria. Despite its widespread use, no optimization of the culture conditions and nisin induction has been carried out to obtain maximum yields. As a model system induced production of lysostaphin, an antibacterial protein (mainly against Staphylococcus aureus produced by S. simulans biovar. Staphylolyticus, was used. Three main areas need optimization for maximum yields: cell density, nisin-controlled induction and protein production, and parameters specific for the target-protein. Results In a series of pH-controlled fermentations the following parameters were optimized: pH of the culture, use of NaOH or NH4OH as neutralizing agent, the addition of zinc and phosphate, the fermentation temperature, the time point of induction (cell density of the culture, the amount of nisin added for induction and the amount of three basic medium components, i.e. yeast extract, peptone and lactose. For each culture growth and lysostaphin production was followed. Lysostaphin production yields depended on all parameters that were varied. In the course of the optimization a three-fold increase in lysostaphin yield was achieved from 100 mg/l to 300 mg/l. Conclusion Protein production with the NICE gene expression system in L. lactis strongly depends on the medium composition, the fermentation parameters and the amount of nisin added for induction. Careful optimization of key parameters lead to a significant increase in the yield of the target protein.

  8. Food Safety: Secretome of Lactococcus lactis and Listeria monocytogenes in competition.

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    Isabella Alloggio

    2015-07-01

    Full Text Available Listeria monocytogenes (LM is a foodborne pathogen responsible of listeriosis. In the spreading of this pathology, milk and dairy products are key reservoir for this pathogen1. Food processing represents one of the major steps that could be linked to LM growth. Inhibition of LM growth through competition of Lactococcus lactis (LAC could represent a solution to this problem. Exoproteome of LM and two different strains of Lactic Acid Bacteria in co-culture have been studied in order to highlight mechanisms of bacterial competition useful to improve food safety. Two different strains of LAC and one strain of LM were cultivated in appropriate medium cultures (BHI, also in competition. Filtrated cultures (SECRETOME were lyophilized and resuspended for proteomics analysis. Shotgun analysis on each secretome was performed on nano UPLC-MS system. Obtained data reveal, during competition, the higher production by LM of moonlighting protein Enolase and Glucose 6 Phosphate isomerase, of Septation ring formation regulator EzrA, involved into cell replication and the lower secretion of Endopeptidase P60. In parallel, L. lactis produced higher amounts of Secreted 45 kDa protein and switched from lantibiotic Nisin A production to Nisin Z production. In competition with LM, LAC strain investigated produce higher amounts of Secreted 45 kDa protein with peptidoglycan lytic activity and the selective secretion of Nisin Z probably to improve lantibiotic solubility in less acidic environment. Next step will be validation of obtained results in dairy products. These results are of interesting to design new strategies of fighting LM as contaminant in food from animal origin.Work supported by Ministry of Health-CCM “Milano EXPO 2015 Project: Garantire la sicurezza alimentare- Valorizzare le produzioni”

  9. Fate of Lactococcus lactis starter cultures during late ripening in cheese models.

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    Ruggirello, Marianna; Cocolin, Luca; Dolci, Paola

    2016-10-01

    The presence of Lactococcus lactis, commonly employed as starter culture, was, recently, highlighted and investigated during late cheese ripening. Thus, the main goal of the present study was to assess the persistence and viability of this microorganism throughout manufacturing and ripening of model cheeses. Eight commercial starters, constituted of L. lactis subsp. lactis and L. lactis subsp. cremoris, were inoculated in pasteurized milk in order to manufacture miniature cheeses, ripened for six months. Samples were analysed at different steps (milk after inoculum, curd after cutting, curd after pressing and draining, cheese immediately after salting and cheese at 7, 15, 30, 60, 90, 120, 150 and 180 days of ripening) and submitted to both culture-dependent (traditional plating on M17) and -independent analysis (reverse transcription-quantitative PCR). On the basis of direct RNA analysis, L. lactis populations were detected in all miniature cheeses up to the sixth month of ripening, confirming the presence of viable cells during the whole ripening process, including late stages. Noteworthy, L. lactis was detected by RT-qPCR in cheese samples also when traditional plating failed to indicate its presence. This discrepancy could be explain with the fact that lactococci, during ripening process, enter in a stressed physiological state (viable not culturable, VNC), which might cause their inability to grow on synthetic medium despite their viability in cheese matrix. Preliminary results obtained by "resuscitation" assays corroborated this hypothesis and 2.5% glucose enrichment was effective to recover L. lactis cells in VNC state. The capability of L. lactis to persist in late ripening, and the presence of VNC cells which are known to shift their catabolism to peptides and amino acids consumption, suggests a possible technological role of this microorganism in cheese ripening with a possible impact on flavour formation.

  10. Physiological adaptation of the bacterium Lactococcus lactis in response to the production of human CFTR.

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    Steen, Anton; Wiederhold, Elena; Gandhi, Tejas; Breitling, Rainer; Slotboom, Dirk Jan

    2011-07-01

    Biochemical and biophysical characterization of CFTR (the cystic fibrosis transmembrane conductance regulator) is thwarted by difficulties to obtain sufficient quantities of correctly folded and functional protein. Here we have produced human CFTR in the prokaryotic expression host Lactococcus lactis. The full-length protein was detected in the membrane of the bacterium, but the yields were too low (proteins) for in vitro functional and structural characterization, and induction of the expression of CFTR resulted in growth arrest. We used isobaric tagging for relative and absolute quantitation based quantitative proteomics to find out why production of CFTR in L. lactis was problematic. Protein abundances in membrane and soluble fractions were monitored as a function of induction time, both in CFTR expression cells and in control cells that did not express CFTR. Eight hundred and forty six proteins were identified and quantified (35% of the predicted proteome), including 163 integral membrane proteins. Expression of CFTR resulted in an increase in abundance of stress-related proteins (e.g. heat-shock and cell envelope stress), indicating the presence of misfolded proteins in the membrane. In contrast to the reported consequences of membrane protein overexpression in Escherichia coli, there were no indications that the membrane protein insertion machinery (Sec) became overloaded upon CFTR production in L. lactis. Nutrients and ATP became limiting in the control cells as the culture entered the late exponential and stationary growth phases but this did not happen in the CFTR expressing cells, which had stopped growing upon induction. The different stress responses elicited in E. coli and L. lactis upon membrane protein production indicate that different strategies are needed to overcome low expression yields and toxicity.

  11. Over-expressed CmbT multidrug resistance transporter improves the fitness of Lactococcus lactis

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    Filipić Brankica

    2013-01-01

    Full Text Available The influence of the over-expression of CmbT multidrug resistance transporter on the growth rate of Lactococcus lactis NZ9000 was studied. L. lactis is a lactic acid bacteria (LAB widely used as a starter culture in dairy industry. Recently characterized CmbT MDR transporter in L. lactis confers resistance to a wide variety of toxic compounds as well as to some clinically relevant antibiotics. In this study, the cmbT gene was over-expressed in the strain L. lactis NZ9000 in the presence of nisin inducer. Over-expression of the cmbT gene in L. lactis NZ9000 was followed by RT-PCR. The obtained results showed that the cmbT gene was successfully over-expressed by addition of sub-inhibitory amounts of nisin. Growth curves of L. lactis NZ9000/pCT50 over-expressing the cmbT gene and L. lactis NZ9000 control strain were followed in the rich medium as well as in the chemically defined medium in the presence solely of methionine (0.084 mM or mix of methionine and cysteine (8.4 mM and 8.2 mM, respectively. Resulting doubling times revealed that L. lactis NZ9000/pCT50 had higher growth rate comparing to the control strain. This could be a consequence of the CmbT efflux activity, which improves the fitness of the host bacterium through the elimination of toxic compounds from the cell.

  12. Enhancement of nisin production by Lactococcus lactis in periodically re-alkalized cultures.

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    Guerra, Nelson Pérez; Castro, Lorenzo Pastrana

    2003-10-01

    Synthesis of nisin as well as biomass production by Lactococcus lactis subsp. lactis CECT (Colección Española de Cultivos Tipo) 539 on both hydrolysed mussel-processing waste and whey medium were followed in three fixed volume fed-batch fermentations, with re-alkalization cycles. The two cultures on mussel-processing waste (MPW) were fed with a 240 g/l concentrated glucose and with a concentrated MPW (about 100 g of glucose/l). The culture on whey was fed with a mixture of concentrated whey (48 g of total sugars/l) and a 400 g/l concentrated lactose. The three cultures were mainly characterized with higher nisin titres [49.7, 109.6 and 124.7 bacteriocin activity units (AU)/ml respectively] compared with the batch process on de Man, Rogosa and Sharpe [(1960) J. Appl. Bacteriol. 23, 130-135] medium (49.6 AU/ml), MPW (9.5 AU/ml) and whey (22.5 AU/ml) [1 AU/ml is the amount of antibacterial compound needed to obtain 50% growth inhibition (LD50) compared with control tubes]. In the three fed-batch cultures a shift from homolactic to mixed-acid fermentation was observed, and other products (acetic acid, butane-2,3-diol or ethanol) in addition to lactic acid were detectable in the medium. However, their contributions to the total antibacterial activity of the post-incubates (the cell-free culture supernatant obtained at the end of the fermentation process) of L. lactis CECT 539 against Carnobacterium piscicola CECT 4020 were very low.

  13. Characterization of plasmids in a human clinical strain of Lactococcus garvieae.

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    Mónica Aguado-Urda

    Full Text Available The present work describes the molecular characterization of five circular plasmids found in the human clinical strain Lactococcus garvieae 21881. The plasmids were designated pGL1-pGL5, with molecular sizes of 4,536 bp, 4,572 bp, 12,948 bp, 14,006 bp and 68,798 bp, respectively. Based on detailed sequence analysis, some of these plasmids appear to be mosaics composed of DNA obtained by modular exchange between different species of lactic acid bacteria. Based on sequence data and the derived presence of certain genes and proteins, the plasmid pGL2 appears to replicate via a rolling-circle mechanism, while the other four plasmids appear to belong to the group of lactococcal theta-type replicons. The plasmids pGL1, pGL2 and pGL5 encode putative proteins related with bacteriocin synthesis and bacteriocin secretion and immunity. The plasmid pGL5 harbors genes (txn, orf5 and orf25 encoding proteins that could be considered putative virulence factors. The gene txn encodes a protein with an enzymatic domain corresponding to the family actin-ADP-ribosyltransferases toxins, which are known to play a key role in pathogenesis of a variety of bacterial pathogens. The genes orf5 and orf25 encode two putative surface proteins containing the cell wall-sorting motif LPXTG, with mucin-binding and collagen-binding protein domains, respectively. These proteins could be involved in the adherence of L. garvieae to mucus from the intestine, facilitating further interaction with intestinal epithelial cells and to collagenous tissues such as the collagen-rich heart valves. To our knowledge, this is the first report on the characterization of plasmids in a human clinical strain of this pathogen.

  14. Pilus biogenesis in Lactococcus lactis: molecular characterization and role in aggregation and biofilm formation.

    Directory of Open Access Journals (Sweden)

    Virginie Oxaran

    Full Text Available The genome of Lactococcus lactis strain IL1403 harbors a putative pilus biogenesis cluster consisting of a sortase C gene flanked by 3 LPxTG protein encoding genes (yhgD, yhgE, and yhhB, called here pil. However, pili were not detected under standard growth conditions. Over-expression of the pil operon resulted in production and display of pili on the surface of lactococci. Functional analysis of the pilus biogenesis machinery indicated that the pilus shaft is formed by oligomers of the YhgE pilin, that the pilus cap is formed by the YhgD pilin and that YhhB is the basal pilin allowing the tethering of the pilus fibers to the cell wall. Oligomerization of pilin subunits was catalyzed by sortase C while anchoring of pili to the cell wall was mediated by sortase A. Piliated L. lactis cells exhibited an auto-aggregation phenotype in liquid cultures, which was attributed to the polymerization of major pilin, YhgE. The piliated lactococci formed thicker, more aerial biofilms compared to those produced by non-piliated bacteria. This phenotype was attributed to oligomers of YhgE. This study provides the first dissection of the pilus biogenesis machinery in a non-pathogenic Gram-positive bacterium. Analysis of natural lactococci isolates from clinical and vegetal environments showed pili production under standard growth conditions. The identification of functional pili in lactococci suggests that the changes they promote in aggregation and biofilm formation may be important for the natural lifestyle as well as for applications in which these bacteria are used.

  15. Coculture-inducible bacteriocin biosynthesis of different probiotic strains by dairy starter culture Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Blaženka Kos

    2011-12-01

    Full Text Available Bacteriocins produced by probiotic strains effectively contribute to colonization ability of probiotic strains and facilitate their establishment in the competitive gut environment and also protect the gut from gastrointestinal pathogens. Moreover, bacteriocins have received considerable attention due to their potential application as biopreservatives, especially in dairy industry. Hence, the objective of this research was to investigate antimicrobial activity of probiotic strains Lactobacillus helveticus M92, Lactobacillus plantarum L4 and Enterococcus faecium L3, with special focus on their bacteriocinogenic activity directed towards representatives of the same or related bacterial species, and towards distant microorganisms including potential food contaminants or causative agents of gut infections. In order to induce bacteriocin production, probiotic cells were cocultivated with Lactococcus lactis subsp. lactis LMG 9450, one of the most important starter cultures in cheese production. The presence of bacteriocin coding genes was investigated by PCR amplification with sequence-specific primers for helveticin and was confirmed for probiotic strain L. helveticus M92. All examined probiotic strains have shown bacteriocinogenic activity against Staphylococcus aureus 3048, Staphylococcus aureus K-144, Escherichia coli 3014, Salmonella enterica serovar Typhimurium FP1, Bacillus subtilis ATCC 6633, Bacillus cereus TM2, which is an important functional treat of probiotic strains significant in competitive exclusion mechanism which provides selective advantage of probiotic strains against undesirable microorganisms in gastrointestinal tract of the host. According to obtained results, living cells of starter culture Lc. lactis subsp. lactis LMG 9450 induced bacteriocin production by examined probiotic strains but starter culture itself was not sensitive to bacteriocin activity.

  16. Expanding the molecular toolbox for Lactococcus lactis: construction of an inducible thioredoxin gene fusion expression system

    LENUS (Irish Health Repository)

    Douillard, Francois P

    2011-08-09

    Abstract Background The development of the Nisin Inducible Controlled Expression (NICE) system in the food-grade bacterium Lactococcus lactis subsp. cremoris represents a cornerstone in the use of Gram-positive bacterial expression systems for biotechnological purposes. However, proteins that are subjected to such over-expression in L. lactis may suffer from improper folding, inclusion body formation and\\/or protein degradation, thereby significantly reducing the yield of soluble target protein. Although such drawbacks are not specific to L. lactis, no molecular tools have been developed to prevent or circumvent these recurrent problems of protein expression in L. lactis. Results Mimicking thioredoxin gene fusion systems available for E. coli, two nisin-inducible expression vectors were constructed to over-produce various proteins in L. lactis as thioredoxin fusion proteins. In this study, we demonstrate that our novel L. lactis fusion partner expression vectors allow high-level expression of soluble heterologous proteins Tuc2009 ORF40, Bbr_0140 and Tuc2009 BppU\\/BppL that were previously insoluble or not expressed using existing L. lactis expression vectors. Over-expressed proteins were subsequently purified by Ni-TED affinity chromatography. Intact heterologous proteins were detected by immunoblotting analyses. We also show that the thioredoxin moiety of the purified fusion protein was specifically and efficiently cleaved off by enterokinase treatment. Conclusions This study is the first description of a thioredoxin gene fusion expression system, purposely developed to circumvent problems associated with protein over-expression in L. lactis. It was shown to prevent protein insolubility and degradation, allowing sufficient production of soluble proteins for further structural and functional characterization.

  17. Evaluation of the rosemary essential oil (Rosmarinus officinalis L. as modulator of bacterial resistanceAvaliação do óleo essencial de alecrim (Rosmarinus officinalis L. como modulador da resistência bacteriana

    Directory of Open Access Journals (Sweden)

    Eudes Silva Velozo

    2012-05-01

    Full Text Available Microorganisms can be transmitted by food causing diseases in humans. The antibiotics commonly used in treatment of these diseases have shown little or no effect, and in view of the resistance that many microorganisms have acquired. This study evaluated the essential oil leaves of Rosmarinus officinalis L. as a modulator of resistance bacterial drug. The essential oil was obtained by hydrodistillation in a Clevenger apparatus for 3 hours. We tested four strains of E.coli resistant ampicillin (AMP and tetracycline (TET and four strains of Salmonella spp. Resistant to nitrofurantoin (NIT. The strains in 0.5 MacFarland scale suspension were inoculated on Mueller Hinton agar, then soaked antibiotic disks with 10 and 20?L oil pure rosemary were placed on the plates. After 24h/37 º C were measured halos around the discs. All strains tested showed susceptibility to the combined action of essential oil with antibiotics tested. The results indicate that the use of promising rosemary essential oil in combination with antibiotics to combat pathogenic bacteria. Diversos microrganismos podem ser veiculados por alimentos causando doenças nos seres humanos. Os antibióticos comumente utilizados no tratamento dessas doenças têm apresentado baixo ou nenhum efeito, tendo em vista à resistência que muitos microrganismos têm adquirido. Diante deste quadro, o objetivo desta pesquisa foi avaliar o óleo essencial das folhas de Rosmarinus officinalis L. como modulador da resistência bacteriana a drogas. O óleo essencial foi obtido através de hidrodestilação em aparelho de Clevenger por 3h. Foram testadas 4 cepas de E.coli resistentes a Amplicilina (AMP e a Tetraciclina (TET e 4 cepas de Salmonella spp. resistentes a Nitrofurantoína (NIT. As cepas em suspensão escala MacFarland 0,5 foram inoculadas em agar Mueller Hinton, em seguida os discos dos antibióticos embebidos com 10 e 20?L do óleo de alecrim puro foram dispostos sobre as placas. Após 24h/37º

  18. Meningoencefalitis Bacteriana. Estudio clínico-epidemiológico. Hospital Pediátrico Provincial de Holguín. 2008-2009.

    Directory of Open Access Journals (Sweden)

    Michel Escalona Martín

    2010-01-01

    Full Text Available Presentó un estudio clínico-epidemiológico de la Meningoencefalitis Bacteriana en el Hospital Pediátrico de Holguín en el período de enero del 2008 a diciembre del 2009. Al ingreso fueron diagnosticados 13 pacientes, al egreso el diagnóstico definitivo fue de 11 pacientes. El grupo de edad más afectado resultó ser hasta los cuatro años y se reportó un mayor número decasos en el primer semestre para ambos años. Las manifestaciones clínicas frecuentes resultaron ser la fiebre, rigidez de nuca, irritabilidad y alteraciones de conciencia. Se cuantificó un mayor número de pacientes con celularidad superior a 1000 x106/L. En más del 50% de los pacientes fueron observadas formas bacterianas en el Gram y el Streptococcus pneumoniae fue el germen predominante. En el año 2008 el 20% de los pacientes falleció y el 40% presentó secuelas, en el 2009 el 33.4% de los pacientes fallecieron y no se reportaron secuelas.

  19. In Vitro characterization of Lactococcus lactis strains Isolated from Iranian Traditional Dairy Products as a Potential Probiotic

    Directory of Open Access Journals (Sweden)

    Fatemeh Nejati

    2015-12-01

    Full Text Available Few studies have been reported regarding probiotic properties of Lactococcus lactis strains although they are extensively used as starter cultures in the production of dairy products. In this study 8 wild isolates of Lactococcus lactis were evaluated in vitro with regard to resistance to simulated gastric and intestinal juices, adherence ability to Caco-2 cells and HT29-MTX-E12 cell lines, anti-microbial activity, hydrophobicity and antibiotic susceptibility. The results revealed that all isolates had better survival after exposure to simulated gastrointestinal tract stresses in comparison to control probiotic Lactobacillus rhamnosus GG. Regarding adherence efficiency, almost all isolates exhibited similar adherence with control. Three isolates showed antibacterial activity against Gram-positive pathogens (Staphylococcus aureus and Listeria monocytogenes through spot-agar method. Almost all isolates (seven out of eight showed similar hydrophobicity to control probiotic. Regarding to antibiotic resistance, all isolates were susceptible to gentamicin, ampicillin, ciprofloxacin, erythromycin, tetracycline, penicillin, kanamycin and nitrofurantoin. Although, further investigations are necessary, it was concluded that strains derived from raw milk and home-made dairy products could be a remarkable reservoir for identification of new potential probiotic strains.

  20. Transcription profiling of interactions between Lactococcus lactis subsp. cremoris SK11 and Lactobacillus paracasei ATCC 334 during Cheddar cheese simulation.

    Science.gov (United States)

    Desfossés-Foucault, Émilie; LaPointe, Gisèle; Roy, Denis

    2014-05-16

    The starter cultures (Lactococcus sp.) and non-starter lactic acid bacteria (mostly Lactobacillus spp.) are essential to flavor development of Cheddar cheese. The aim of this study was to elucidate the transcriptional interaction between Lactococcus lactis subsp. cremoris SK11 and Lactobacillus paracasei ATCC 334 in mixed cultures during simulated Cheddar cheese manufacture (Pearce activity test) and ripening (slurry). Reverse transcription quantitative PCR (RT-qPCR) was used to quantify the expression of 34 genes common to both bacteria and for eight genes specific to either L. lactis subsp. cremoris SK11 or L. paracasei ATCC 334. The multifactorial analysis (MFA) performed on fold change results for each gene revealed that the genes linked to stress, protein and peptide degradation as well as carbohydrate metabolism of L. paracasei ATCC 334 were especially overexpressed in mixed culture with L. lactis subsp. cremoris SK11 during the ripening simulation. For L. lactis subsp. cremoris SK11, genes coding for amino acid metabolism were more expressed during the cheese manufacture simulation, especially in single culture. These results show how complementary functions of starter and NSLAB contribute to activities useful for flavor development.

  1. Empiema por Fusobacterium necrophorum

    OpenAIRE

    ML. Valle Feijoo; M. Rodriguez Arias; A. Cobas Paz; J. De la Fuente Aguado

    2014-01-01

    Resumen La infección sistémica por Fusobacterium necrophorum se caracteriza por la tríada clásica de trombosis de la vena yugular interna, bacteriemia y focos metastásicos y se conoce como Síndrome de Lemierre (SL), sepsis post-angina o necrobacilosis. El compromiso pulmonar precipitado por la embolización séptica es extremadamente común en el SL, sin embargo el F. necrohorum raramente se asila en empiemas sin SL concurrente, por lo que hemos estimado oportuno comunicar un nuevo caso clíni...

  2. Celulitis por citomegalovirus

    OpenAIRE

    2002-01-01

    Las lesiones cutáneas por citomegalovirus (CMV) son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritemato...

  3. Importance of bacterial endotoxin (LPS in endodontics A importância da endotoxina bacteriana (LPS na endodontia atual

    Directory of Open Access Journals (Sweden)

    Mario Roberto Leonardo

    2004-06-01

    Full Text Available New knowledge of the structure and biological activity of endotoxins (LPS has revolutionized concepts concerning their mechanisms of action and forms of inactivation. Since the 1980's, technological advances in microbiological culture and identification have shown that anaerobic microorganisms, especially Gram-negative, predominate in root canals of teeth with pulp necrosis and radiographically visible chronic periapical lesions. Gram-negative bacteria not only have different factors of virulence and generate sub-products that are toxic to apical and periapical tissues, as also contain endotoxin (LPS on their cell wall. This is especially important because endotoxin is released during multiplication or bacterial death, causing a series of biological effects that lead to an inflammatory reaction and resorption of mineralized tissues. Thus, due to the role of endotoxin in the pathogenesis of periapical lesions, we reviewed the literature concerning the biological activity of endotoxin and the relevance of its inactivation during treatment of teeth with pulp necrosis and chronic periapical lesion.O conhecimento mais aprofundado sobre a estrutura e atividade biológica das endotoxinas (LPS revolucionou os conceitos sobre seu mecanismo de ação e formas de inativação. A partir da década de 80, os avanços tecnológicos na cultura e identificação microbiológica demonstraram que, em canais radiculares de dentes portadores de necrose pulpar e lesão periapical crônica, visível radiograficamente, predominam microrganismos anaeróbios, particularmente os gram-negativos. Como se sabe, os microrganismos gram-negativos, além de possuírem diferentes fatores de virulência e gerarem produtos e sub-produtos tóxicos aos tecidos apicais e periapicais, contêm endotoxina em sua parede celular. Esse conhecimento é particularmente importante, uma vez que a endotoxina é liberada durante a multiplicação ou morte bacteriana, exercendo uma série de

  4. AguR is a transmembrane transcription activator of the putrescine biosynthesis operon in Lactococcus lactis, and acts in response to agmatine concentration

    NARCIS (Netherlands)

    Linares, Daniel M; Del Rio, Beatriz; Redruello, Begoña; Ladero, Victor; Martin, Ma Cruz; de Jong, Anne; Kuipers, Oscar P; Fernandez, Maria; Alvarez, Miguel A

    2015-01-01

    Dairy industry fermentative processes mostly use Lactococcus lactis as a starter. However, some dairy L. lactis strains produce putrescine - a biogenic amine that raises food safety and spoilage concerns - via the agmatine deiminase pathway (AGDI). The enzymatic activities responsible for putrescine

  5. Transcriptional activation of the glycolytic las operon and catabolite repression of the gal operon in Lactococcus lactis are mediated by the catabolite control protein CcpA

    NARCIS (Netherlands)

    Luesink, Evert J.; Herpen, René E.M.A. van; Grossiord, Benoît P.; Kuipers, Oscar P.; Vos, Willem M. de

    1998-01-01

    The Lactococcus lactis ccpA gene, encoding the global regulatory protein CcpA, was identified and characterized. Northern blot and primer extension analyses showed that the L. lactis ccpA gene is constitutively transcribed from a promoter that does not contain a cre sequence. Inactivation of the ccp

  6. How to distinguish between the vacuum cleaner and flippase mechanisms of the LmrA multi-drug transporter in Lactococcus lactis

    NARCIS (Netherlands)

    Hofmeyr, JHS; Rohwer, JM; Snoep, JL; Westerhoff, HV; Konings, WN

    2002-01-01

    A numerical model of the LmrA multi-drug transport system of Lactococcus lactis is used to explore the possibility of distinguishing experimentally between two putative transport mechanisms, i.e., the vacuum-cleaner and the flippase mechanisms. This comparative model also serves as an example of num

  7. Biosynthesis and secretion of a precursor of nisin Z by Lactococcus lactis, directed by the leader peptide of the homologous lantibiotic subtilin from Bacillus subtilis

    NARCIS (Netherlands)

    Kuipers, Oscar P.; Rollema, Harry S.; Vos, Willem M. de; Siezen, Roland J.

    1993-01-01

    The DNA sequence encoding the leader peptide of the lantibiotic subtilin from Bacillus subtilis was fused to the sequence encoding pronisin Z, and this hybrid gene was expressed in a Lactococcus lactis strain that produces nisin A. This strain simultaneously secreted nisin A and a protein of approxi

  8. Recombinant pediocin in Lactococcus lactis : increased production by propeptide fusion and improved potency by co-production with PedC

    NARCIS (Netherlands)

    Back, Alexandre; Borges, Frederic; Mangavel, Cecile; Paris, Cedric; Rondags, Emmanuel; Kapel, Romain; Aymes, Arnaud; Rogniaux, Helene; Pavlovic, Marija; van Heel, Auke J.; Kuipers, Oscar P.; Revol-Junelles, Anne-Marie; Cailliez-Grimal, Catherine

    2016-01-01

    We describe the impact of two propeptides and PedC on the production yield and the potency of recombinant pediocins produced in Lactococcus lactis. On the one hand, the sequences encoding the propeptides SD or LEISSTCDA were inserted between the sequence encoding the signal peptide of Usp45 and the

  9. Lactococcus lactis TrxD represents a subgroup of thioredoxins prevalent in Gram-positive bacteria containing WCXDC active site motifs

    DEFF Research Database (Denmark)

    Björnberg, Olof; Efler, Petr; Epie, Denis Ebong

    2014-01-01

    Three protein disulfide reductases of the thioredoxin superfamily from the industrially important Gram-positive Lactococcus lactis (LlTrxA, LlTrxD and LlNrdH) are compared to the "classical" thioredoxin from Escherichia coil (EcTrx1). LlTrxA resembles EcTrx1 with a WCGPC active site motif and other...

  10. Distinct contributions of the nisin biosynthesis enzymes NisB and NisC and transporter NisT to prenisin production by Lactococcus lactis

    NARCIS (Netherlands)

    van Saparoea, H. Bart van den Berg; Bakkes, Patrick J.; Moll, Gert N.; Driessen, Arnold J. M.

    2008-01-01

    Several Lactococcus lactis strains produce the lantibiotic nisin. The dedicated enzymes NisB and NisC and the transporter NisT modify and secrete the ribosomally synthesized nisin precursor peptide. NisB can function in the absence of the cyclase NisC, yielding the dehydrated prenisin that lacks the

  11. Genome sequence of Lactococcus garvieae IPLA 31405, a bacteriocin-producing, tetracycline-resistant strain isolated from a raw-milk cheese

    OpenAIRE

    Flórez García, Ana Belén; Reimundo, Pilar; Delgado, Susana; Fernández, Elena; Alegría, Ángel; Guijarro, José A; Mayo Pérez, Baltasar

    2012-01-01

    This work describes the draft genome sequence of Lactococcus garvieae IPLA 31405, isolated from a traditional Spanish cheese. The genome contains a lactose-galactose operon,a bacteriocin locus, two integrated phages, a transposon harboring an active tet(M) gene, and two theta-type plasmid replicons. Genes encoding virulence factors were not recorded. © 2012, American Society for Microbiology.

  12. The purified and functionally reconstituted multidrug transporter LmrA of Lactococcus lactis mediates the transbilayer movement of specific fluorescent phospholipids

    NARCIS (Netherlands)

    Margolles, A; Putman, M; van Veen, HW; Konings, WN

    1999-01-01

    Lactococcus lactis possesses an ATP-binding cassette transporter, LmrA, which is a homolog of the mammalian multidrug resistance (MDR) P-glycoprotein, and is able to transport a broad range of structurally unrelated amphiphilic drugs. A histidine tag was introduced at the N-terminus of LmrA to facil

  13. Molecular Cloning and Nucleotide Sequence of the Gene Encoding the Major Peptidoglycan Hydrolase of Lactococcus lactis, a Muramidase Needed for Cell Separation

    NARCIS (Netherlands)

    Buist, Girbe; Kok, Jan; Leenhouts, Kees J.; Dabrowska, Magdalena; Venema, Gerhardus; Haandrikman, Alfred J.

    1995-01-01

    A gene of Lactococcus lactis subsp, cremoris MG1363 encoding a peptidoglycan hydrolase was identified in a genomic library of the strain in pUC19 by screening Escherichia coli transformants for cell wall lysis activity on a medium containing autoclaved, lyophilized Micrococcus lysodeikticus cells, I

  14. Use of non-growing Lactococcus lactis cell suspensions for production of volatile metabolites with direct relevance for flavour formation during dairy fermentations

    NARCIS (Netherlands)

    Bunt, van de B.; Bron, P.A.; Sijtsma, L.; Vos, de W.M.; Hugenholtz, J.

    2014-01-01

    Background Lactococcus lactis is a lactic acid bacterium that has been used for centuries in the production of a variety of cheeses, as these bacteria rapidly acidify milk and greatly contribute to the flavour of the fermentation end-products. After a short growth phase during cheese ripening L. lac

  15. Transport of β-Casein-derived Peptides by the Oligopeptide Transport System Is a Crucial Step in the Proteolytic Pathway of Lactococcus lactis

    NARCIS (Netherlands)

    Kunji, E.R S; Hagting, A; de Vries, C.J.; Juillard, V.; Haandrikman, A.J; Poolman, B.; Konings, W.N

    1995-01-01

    In the proteolytic pathway of Lactococcus lactis, milk proteins (caseins) are hydrolyzed extracellularly to oligopeptides by the proteinase (PrtP). The fate of these peptides, i.e. extracellular hydrolysis followed by amino acid uptake or transport followed by intracellular hydrolysis, has been addr

  16. Use of a genetically enhanced, pediocin-producing starter culture, Lactococcus lactis subsp. lactis MM217, to control Listeria monocytogenes in cheddar cheese

    NARCIS (Netherlands)

    Buyong, N; Kok, J; Luchansky, JB

    1998-01-01

    Cheddar cheese was prepared with Lactococcus lactis subsp, lactis MM217, a starter culture which contains pMC117 coding for pediocin PA-1, About 75 liters of pasteurized milk (containing ca, 3.6% fat) was inoculated with strain MM217 (ca, 10(6) CFU per ml) and a mixture of three Listeria monocytogen

  17. Identification and functional characterization of the Lactococcus lactis CodY-regulated branched-chain amino acid permease BcaP (CtrA)

    NARCIS (Netherlands)

    den Hengst, CD; Groeneveld, M; Kuipers, OP; Kok, J; Hengst, Chris D. den

    2006-01-01

    Transcriptome analyses have previously revealed that a gene encoding the putative amino acid transporter CtrA (YhdG) is one of the major targets of the pleiotropic regulator CodY in Lactococcus lactis and Bacillus subtilis. The role of ctrA in L. lactis was further investigated with respect to both

  18. Tripeptidase Gene (pepT) of Lactococcus lactis : Molecular Cloning and Nucleotide Sequencing of pepT and Construction of a Chromosomal Deletion Mutant

    NARCIS (Netherlands)

    Mierau, Igor; Haandrikman, Alfred J.; Velterop, Odilia; Tan, Paris S.T.; Leenhouts, Kees L.; Konings, Wilhelmus; Venema, Gerhardus; Kok, Jan

    1994-01-01

    The gene encoding a tripeptidase (pepT) of lactococcus lactis subsp. cremoris (formerly subsp. lactis) MG1363 was cloned from a genomic library in pUC19 and subsequently sequenced. The tripeptidase of L. lactis was shown to be homologous to PepT of Salmonella typhimurium with 47.4% identity in the d

  19. Draft genome sequence of Lactococcus garvieae str. PAQ102015-99, an outbreak strain isolated from a commercial trout farm in the Northwestern United States.

    Science.gov (United States)

    We announce the draft genome assembly of Lactococcus garvieae str. PAQ102015-99, a recently isolated strain from an outbreak of lactococcosis at a commercial trout farm in the Northwestern US. The draft genome comprises 14 contigs totaling 2,068,357 bp with an N50 of 496,618 bp and average G+C conte...

  20. Análisis epidemiológico de la infección por Chlamydia Trachomatis en Gipuzkoa (2006-2015): Prevalencia en gestantes, impacto en la población y genotipos circulantes

    OpenAIRE

    Piñeiro Vázquez, Luis Darío

    2016-01-01

    257 p. La infección por Chlamydia trachomatis es un importante y creciente problema de salud pública mundial y actualmente la primera causa bacteriana de infecciones de transmisión sexual. Las principales manifestaciones clínicas son la cervicitis en las mujeres y la uretritis en los hombres, pero frecuentemente puede ser asintomática diseminándose entre la población sin ser diagnosticada hasta la aparición de las posibles complicaciones y secuelas. La incidencia de esta infección es mayor...

  1. Secretion of biologically active interferon-gamma inducible protein-10 (IP-10 by Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Saucedo-Cardenas Odila

    2008-07-01

    Full Text Available Abstract Background Chemokines are a large group of chemotactic cytokines that regulate and direct migration of leukocytes, activate inflammatory responses, and are involved in many other functions including regulation of tumor development. Interferon-gamma inducible-protein-10 (IP-10 is a member of the C-X-C subfamily of the chemokine family of cytokines. IP-10 specifically chemoattracts activated T lymphocytes, monocytes, and NK cells. IP-10 has been described also as a modulator of other antitumor cytokines. These properties make IP-10 a novel therapeutic molecule for the treatment of chronic and infectious diseases. Currently there are no suitable live biological systems to produce and secrete IP-10. Lactococcus lactis has been well-characterized over the years as a safe microorganism to produce heterologous proteins and to be used as a safe, live vaccine to deliver antigens and cytokines of interest. Here we report a recombinant strain of L. lactis genetically modified to produce and secrete biologically active IP-10. Results The IP-10 coding region was isolated from human cDNA and cloned into an L. lactis expression plasmid under the regulation of the pNis promoter. By fusion to the usp45 secretion signal, IP-10 was addressed out of the cell. Western blot analysis demonstrated that recombinant strains of L. lactis secrete IP-10 into the culture medium. Neither degradation nor incomplete forms of IP-10 were detected in the cell or supernatant fractions of L. lactis. In addition, we demonstrated that the NICE (nisin-controlled gene expression system was able to express IP-10 "de novo" even two hours after nisin removal. This human IP-10 protein secreted by L. lactis was biological active as demonstrated by Chemotaxis assay over human CD3+T lymphocytes. Conclusion Expression and secretion of mature IP-10 was efficiently achieved by L. lactis forming an effective system to produce IP-10. This recombinant IP-10 is biologically active as

  2. High efficiency electrotransformation of Lactococcus lactis spp. lactis cells pretreated with lithium acetate and dithiothreitol

    Directory of Open Access Journals (Sweden)

    Filioussis George

    2007-03-01

    Full Text Available Abstract Background A goal for the food industry has always been to improve strains of Lactococcus lactis and stabilize beneficial traits. Genetic engineering is used extensively for manipulating this lactic acid bacterium, while electropolation is the most widely used technique for introducing foreign DNA into cells. The efficiency of electrotransformation depends on the level of electropermealization and pretreatment with chemicals which alter cell wall permeability, resulting in improved transformation efficiencies is rather common practice in bacteria as in yeasts and fungi. In the present study, treatment with lithium acetate (LiAc and dithiothreitol (DTT in various combinations was applied to L. lactis spp. lactis cells of the early-log phase prior to electroporation with plasmid pTRKH3 (a 7.8 kb shuttle vector, suitable for cloning into L. lactis. Two strains of L. lactis spp. lactis were used, L. lactis spp. lactis LM0230 and ATCC 11454. To the best of our knowledge these agents have never been used before with L. lactis or other bacteria. Results Electrotransformation efficiencies of up to 105 transformants per μg DNA have been reported in the literature for L. lactis spp.lactis LM0230. We report here that treatment with LiAc and DDT before electroporation increased transformation efficiency to 225 ± 52.5 × 107 transformants per μg DNA, while with untreated cells or treated with LiAc alone transformation efficiency approximated 1.2 ± 0.5 × 105 transformants per μg DNA. Results of the same trend were obtained with L. lactis ATCC 11454, although transformation efficiency of this strain was significantly lower. No difference was found in the survival rate of pretreated cells after electroporation. Transformation efficiency was found to vary directly with cell density and that of 1010 cells/ml resulted in the highest efficiencies. Following electrotransformation of pretreated cells with LiAc and DDT, pTRKH3 stability was examined

  3. Production of Recombinant Peanut Allergen Ara h 2 using Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Frøkiær Hanne

    2007-08-01

    Full Text Available Abstract Background Natural allergen sources can supply large quantities of authentic allergen mixtures for use as immunotherapeutics. However, such extracts are complex, difficult to define, vary from batch to batch, which may lead to unpredictable efficacy and/or unacceptable levels of side effects. The use of recombinant expression systems for allergen production can alleviate some of these issues. Several allergens have been tested in high-level expression systems and in most cases show immunereactivity comparable to their natural counterparts. The gram positive lactic acid bacterium Lactococcus lactis is an attractive microorganism for use in the production of protein therapeutics. L. lactis is considered food grade, free of endotoxins, and is able to secrete the heterologous product together with few other native proteins. Hypersensitivity to peanut represents a serious allergic problem. Some of the major allergens in peanut have been described. However, for therapeutic usage more information about the individual allergenic components is needed. In this paper we report recombinant production of the Ara h 2 peanut allergen using L. lactis. Results A synthetic ara h 2 gene was cloned into an L. lactis expression plasmid containing the P170 promoter and the SP310mut2 signal sequence. Flask cultures grown overnight showed secretion of the 17 kDa Ara h 2 protein. A batch fermentation resulted in 40 mg/L recombinant Ara h 2. Purification of Ara h 2 from the culture supernatant was done by hydrophobic exclusion and size separation. Mass spectrometry and N-terminal analysis showed a recombinant Ara h 2 of full length and correctly processed by the signal peptidase. The immunological activity of recombinant Ara h 2 was analysed by ELISA using antibodies specific for native Ara h 2. The recombinant Ara h 2 showed comparable immunereactivity to that of native Ara h 2. Conclusion Recombinant production of Ara h 2 using L. lactis can offer high yields

  4. Fine tuning of the lactate and diacetyl production through promoter engineering in Lactococcus lactis.

    Directory of Open Access Journals (Sweden)

    Tingting Guo

    Full Text Available Lactococcus lactis is a well-studied bacterium widely used in dairy fermentation and capable of producing metabolites with organoleptic and nutritional characteristics. For fine tuning of the distribution of glycolytic flux at the pyruvate branch from lactate to diacetyl and balancing the production of the two metabolites under aerobic conditions, a constitutive promoter library was constructed by randomizing the promoter sequence of the H(2O-forming NADH oxidase gene in L. lactis. The library consisted of 30 promoters covering a wide range of activities from 7,000 to 380,000 relative fluorescence units using a green fluorescent protein as reporter. Eleven typical promoters of the library were selected for the constitutive expression of the H(2O-forming NADH oxidase gene in L. lactis, and the NADH oxidase activity increased from 9.43 to 58.17-fold of the wild-type strain in small steps of activity change under aerobic conditions. Meanwhile, the lactate yield decreased from 21.15 ± 0.08 mM to 9.94 ± 0.07 mM, and the corresponding diacetyl production increased from 1.07 ± 0.03 mM to 4.16 ± 0.06 mM with the intracellular NADH/NAD(+ ratios varying from 0.711 ± 0.005 to 0.383 ± 0.003. The results indicated that the reduced pyruvate to lactate flux was rerouted to the diacetyl with an almost linear flux variation via altered NADH/NAD(+ ratios. Therefore, we provided a novel strategy to precisely control the pyruvate distribution for fine tuning of the lactate and diacetyl production through promoter engineering in L. lactis. Interestingly, the increased H(2O-forming NADH oxidase activity led to 76.95% lower H(2O(2 concentration in the recombinant strain than that of the wild-type strain after 24 h of aerated cultivation. The viable cells were significantly elevated by four orders of magnitude within 28 days of storage at 4°C, suggesting that the increased enzyme activity could eliminate H(2O(2 accumulation and prolong cell survival.

  5. Peritonite bacteriana espontânea: impacto das mudanças da microbiologia Spontaneous bacterial peritonitis: impact of microbiological changes

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    Paulo Roberto Lerias de Almeida

    2007-03-01

    Full Text Available RACIONAL: A peritonite bacteriana espontânea é uma complicação grave nos pacientes cirróticos com ascite, sendo as alterações das características microbiológicas relatadas nos últimos anos de impacto na escolha do tratamento antibiótico. OBJETIVO: Avaliar as mudanças na epidemiologia e na resistência antibiótica de bactérias causadoras de peritonite bacteriana espontânea em um período de 7 anos. MÉTODOS: Foram avaliados retrospectivamente todos os casos de pacientes cirróticos com peritonite bacteriana espontânea cuja cultura do líquido de ascite foi positiva, sendo estudados dois períodos: 1997-1998 e 2002-2003. Foram verificados os microorganismos mais freqüentes e a sensibilidade in vitro aos antibióticos. RESULTADOS: No primeiro período (1997-1998 houve 33 casos, sendo 3 (9% com infecção polimicrobiana. As bactérias mais freqüentes foram: E. coli em 13 (36,11%, estafilococos coagulase-negativos em 6 (16,66%, K. pneumoniae em 5 (13,88%, S. aureus em 4 (11,11% e S. faecalis em 3 (8,33%. Em 2002-2003, houve 43 casos, sendo 2 (5% com infecção polimicrobiana. As bactérias mais freqüentes foram: estafilococos coagulase-negativos em 16 (35,55% S. aureus em 8 (17,77%, E. coli em 7 (15,55% e K. pneumoniae em 3 (6,66%. Nenhum paciente realizava profilaxia para peritonite bacteriana espontânea. A prevalência de S. aureus meticilino-resistentes aumentou, no decorrer desse período, de 25% para 75%, tendo a resistência desse patógeno às quinolonas e a sulfametoxazol-trimetoprim evoluído de 25% para 50%; somente a vancomicina demonstrou atividade absoluta no decorrer do referido período. Da mesma forma, a prevalência de E. coli resistente às cefalosporinas de terceira geração e às quinolonas aumentou de 0% para 16%. CONCLUSÃO: Houve modificação da população bacteriana causadora de peritonite bacteriana espontânea, com freqüência aumentada de microorganismos gram-positivos, bem como houve aumento da

  6. Efeito da nisina na contagem de Lactococcus e Lactobacillus em queijo Minas artesanal da região de Araxá - MG

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    Denise Sobral

    2013-04-01

    Full Text Available Os queijos Minas artesanais da região de Araxá são produzidos nos municípios de Araxá, Campos Altos, Ibiá, Pedrinópolis, Perdizes, Sacramento, Santa Juliana, Uberaba, Conquista, Pratinha e Tapira. Estes queijos, por serem fabricados com leite cru e serem bastante manipulados, podem veicular micro-organismos patogênicos, provenientes do próprio leite e também das condições higiênico-sanitárias às quais são submetidos. A nisina pode auxiliar na redução da contaminação destes queijos, aliada às boas práticas de fabricação e de obtenção do leite e é um produto de fácil utilização. A bacteriocina atua contra bactérias Gram positivas, sendo algumas delas patogênicas, como o Staphylococcus aureus. No entanto, a nisina também pode inibir as bactérias láticas, dependendo da dose utilizada na fabricação de queijos e, consequentemente, pode prejudicar as características sensoriais desejadas no queijo artesanal. Sendo assim, o objetivo deste trabalho foi avaliar o efeito da adição de diferentes concentrações de nisina sobre o comportamento de dois grupos de bactérias láticas, Lactococcus e Lactobacillus, em queijo Minas artesanal da região de Araxá, durante o período de 60 dias de maturação. O resultado da pesquisa foi satisfatório, pois se verificou que a nisina não interferiu na multiplicação destes micro-organismos ao longo da maturação dos queijos Minas artesanais da região de Araxá.

  7. Celulitis por citomegalovirus

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    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

  8. Engineering the cell surface display of cohesins for assembly of cellulosome-inspired enzyme complexes on Lactococcus lactis

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    Wieczorek Andrew S

    2010-09-01

    Full Text Available Abstract Background The assembly and spatial organization of enzymes in naturally occurring multi-protein complexes is of paramount importance for the efficient degradation of complex polymers and biosynthesis of valuable products. The degradation of cellulose into fermentable sugars by Clostridium thermocellum is achieved by means of a multi-protein "cellulosome" complex. Assembled via dockerin-cohesin interactions, the cellulosome is associated with the cell surface during cellulose hydrolysis, forming ternary cellulose-enzyme-microbe complexes for enhanced activity and synergy. The assembly of recombinant cell surface displayed cellulosome-inspired complexes in surrogate microbes is highly desirable. The model organism Lactococcus lactis is of particular interest as it has been metabolically engineered to produce a variety of commodity chemicals including lactic acid and bioactive compounds, and can efficiently secrete an array of recombinant proteins and enzymes of varying sizes. Results Fragments of the scaffoldin protein CipA were functionally displayed on the cell surface of Lactococcus lactis. Scaffolds were engineered to contain a single cohesin module, two cohesin modules, one cohesin and a cellulose-binding module, or only a cellulose-binding module. Cell toxicity from over-expression of the proteins was circumvented by use of the nisA inducible promoter, and incorporation of the C-terminal anchor motif of the streptococcal M6 protein resulted in the successful surface-display of the scaffolds. The facilitated detection of successfully secreted scaffolds was achieved by fusion with the export-specific reporter staphylococcal nuclease (NucA. Scaffolds retained their ability to associate in vivo with an engineered hybrid reporter enzyme, E. coli β-glucuronidase fused to the type 1 dockerin motif of the cellulosomal enzyme CelS. Surface-anchored complexes exhibited dual enzyme activities (nuclease and β-glucuronidase, and were

  9. Meningitis por Kluyvera sp. en una paciente con una derivación lumbo-peritoneal: reporte de un caso

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    Danny Paredes-Rodríguez

    2002-09-01

    Full Text Available Describimos el caso de una paciente portadora de una derivación lumbo- peritoneal, que desarrolló una meningitis bacteriana en la cual Kluyvera sp. se aisló del líquido cefalorraquídeo. En nuestro conocimiento este es el primer caso reportado de infección del SNC por este microorganismo. Esta bacteria era sensible a cefalosporinas de tercera generación y se logró la resolución con Cefotaxime. El Género Kluyvera comprende tres especies infrecuentemente aisladas de muestras clínicas. Se puede asociar a infecciones desde leves a severas y posiblemente se favorece en un huésped inmunocomprometido.

  10. Nisin Z Production by Lactococcus lactis subsp. cremoris WA2-67 of Aquatic Origin as a Defense Mechanism to Protect Rainbow Trout (Oncorhynchus mykiss, Walbaum) Against Lactococcus garvieae.

    Science.gov (United States)

    Araújo, Carlos; Muñoz-Atienza, Estefanía; Pérez-Sánchez, Tania; Poeta, Patrícia; Igrejas, Gilberto; Hernández, Pablo E; Herranz, Carmen; Ruiz-Zarzuela, Imanol; Cintas, Luis M

    2015-12-01

    Probiotics represent an alternative to chemotherapy and vaccination to control fish diseases, including lactococcosis caused by Lactococcus garvieae. The aims of this study were (i) to determine the in vitro probiotic properties of three bacteriocinogenic Lactococcus lactis subsp. cremoris of aquatic origin, (ii) to evaluate in vivo the ability of L. cremoris WA2-67 to protect rainbow trout (Oncorhynchus mykiss, Walbaum) against infection by L. garvieae, and (iii) to demonstrate the role of nisin Z (NisZ) production as an anti-infective mechanism. The three L. cremoris strains survived in freshwater at 18 °C for 7 days, withstood exposure to pH 3.0 and 10 % (v/v) rainbow trout bile, and showed different cell surface hydrophobicity (37.93-58.52 %). The wild-type NisZ-producer L. cremoris WA2-67 and its non-bacteriocinogenic mutant L. cremoris WA2-67 ∆nisZ were administered orally (10(6) CFU/g) to rainbow trout for 21 days and, subsequently, fish were challenged with L. garvieae CLG4 by the cohabitation method. The fish fed with the bacteriocinogenic strain L. cremoris WA2-67 reduced significantly (p < 0.01) the mortality (20 %) compared to the fish treated with its non-bacteriocinogenic knockout isogenic mutant (50 %) and the control (72.5 %). We demonstrated the effectiveness of L. cremoris WA2-67 to protect rainbow trout against infection with the invasive pathogen L. garvieae and the relevance of NisZ production as an anti-infective mechanism. This is the first report demonstrating the effective in vivo role of LAB bacteriocin (NisZ) production as a mechanism to protect fish against bacterial infection. Our results suggest that the wild-type NisZ-producer strain L. cremoris WA2-67 could be used in fish farming to prevent lactococcosis in rainbow trout.

  11. Antagonisme entre les bactéries mésophiles et les bactéries lactiques du genre Lactococcus isolées du lait de jument et recherche des bactériocine

    OpenAIRE

    BELABBES, Souad

    2015-01-01

    This work is revealed the existence of antagonistic effect betweèiic c swaiu «fit& gmm Ladococcus sp mares milk and pathogenic species by i1ifiï dise ïnhditory factors produced by these bacteria, which can be irganiv hages, bydrogen peroxide or bacteriocins. Ail pathogens were inhibited by lactic strains tested secrete organic acids, hydrogen peroxide and bacteriocins but flot lodge phages. Ail strains belonging to lactic Lactococcus lactis and Lactococcus diacetylactis o...

  12. Bacterial survival rate on toothbrushes and their decontamination with antimicrobial solutions Taxa de sobrevivência bacteriana em escovas dentais e sua descontaminação com soluções antimicrobianas

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    Sandra Sato

    2004-06-01

    Full Text Available The purpose of this study was to evaluate bacterial survival rate on toothbrushes after brushing and the efficacy of their decontamination by spraying antimicrobial solutions. Thirty subjects were instructed to spray the solutions on toothbrush bristles after brushing. Each volunteer tested three sprays, one solution per week; the sprays were labeled spray 1 (cetylpyridinium chloride - CPC - and basic formulation, 2 (basic formulation only and 3 (control - sterile tap water. At the end of each week, the brushes were collected and sonicated in Letheen Broth®; the suspensions were ten-fold diluted and the dilutions were plated on various culture media. Anaerobic bacteria, evaluated by colony count of black pigment producing organisms on Ask medium, were recovered from 83.3% of the samples, Streptococci from 80% and aerobic Gram-negative bacilli from 46.7% of them in the control tests. There was a significant decrease in toothbrush contamination with antimicrobial sprays 1 and 2, the first showing the greatest decrease on bacterial counts.O propósito deste estudo foi avaliar a taxa de sobrevivência bacteriana em escovas dentais após a escovação e a eficácia na sua descontaminação pelo borrifamento de soluções antimicrobianas. Trinta indivíduos foram instruídos a borrifar as soluções nas cerdas das escovas após a escovação. Cada voluntário testou três sprays, uma solução por semana; os sprays foram rotulados spray 1 (cloreto de cetilpiridínio - CCP - e formulação básica, 2 (formulação básica apenas e 3 (controle - água de torneira esterilizada. Ao final de cada semana, as escovas eram recolhidas e introduzidas no caldo Letheen®, submetidas a ultra-som, à diluição decimal seriada e as suspensões semeadas em vários meios de cultura. As bactérias anaeróbias, avaliadas pela contagem de colônias de microrganismos produtores de pigmento negro no meio Ask, foram recuperadas em 83,3% das amostras, estreptococos em 80

  13. Efeito do cultivo da soja na dinâmica da população bacteriana, em solos de cerrado Effects of soybean cultivation on the bacterial population dynamics in cerrado soils

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    JOÃO CARLOS PEREIRA

    2000-06-01

    Full Text Available Este trabalho teve por objetivo avaliar a influência do cultivo da soja sobre a dinâmica da população bacteriana, em dois solos de Cerrado do Estado de São Paulo, originalmente cobertos com Paspalum notatum (em Barretos e Brachiaria decumbens (em S��o Carlos. Nesses solos, a densidade da população de bactérias em geral variou de 398,1 x 10³ a 467,7 x 10³ e de 123 x 10³ a 218,8 x 10³ ufc (unidades formadoras de colônias/g de solo seco, respectivamente. O cultivo da soja, em ambos os solos, resultou em incrementos variados nos números de ufc/g de solo seco da população de bactérias em geral, das resistentes aos antibióticos estreptomicina e cloranfenicol, e de actinomicetos. A população de actinomicetos ocorreu no solo principalmente como esporos, e as variações das relações esporos/hifas entre os solos não-rizosférico e rizosférico não foram significativas. Os resultados evidenciam que o cultivo da soja influenciou de forma diferenciada a população desses solos.The effect of soybean cultivation on the population dynamics of the bacterial community was evaluated in two "Cerrado" soils of São Paulo State, Brazil. The experimental areas, in the vicinities of the cities of São Carlos and Barretos, were previously cultivated, respectively, with Paspalum notatum and Brachiaria decumbens. The bacterial population densities in these soils varied from 398.1 x 10³ to 467.7 x 10³ cfu (colony forming units and from 123 x 10³ to 218.8 x 10³ cfu/g of dried soil, respectively, in São Carlos and Barretos soils. Soybean cultivation in both soils resulted in increments in the total bacterial population density, in the actinomycetes population, and in the bacterial population resistant to the antibiotics streptomycin and chloramphenicol. Actinomycetes were present in these soils mainly as spores. Soybean cultivation did not alter the actinomycetes spores/hyphae ratio when comparing rhizospheric and non-rhizospheric soils

  14. Vigilancia de los niveles de uso de antibióticos y perfiles de resistencia bacteriana en hospitales de tercer nivel de la Ciudad de México Surveillance of antibiotic utilization and bacterial resistance profiles in tertiary level hospitals in Mexico City

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    Lilia Benavides-Plascencia

    2005-06-01

    Full Text Available OBJETIVO: Determinar los niveles de uso de antibióticos y el perfil de resistencia de las bacterias nosocomiales, e identificar y proponer estrategias para disminuir la resistencia a los antibióticos. MATERIAL Y MÉTODOS: Estudio descriptivo, retrolectivo (1994-1995, hecho en seis hospitales de tercer nivel de la Ciudad de México. RESULTADOS: La resistencia del grupo hospitalario fue de 86%, mientras que el consumo total de antibióticos por institución varió entre 44 y 195 dosis diarias definidas/100 camas-día. CONCLUSIONES: Se identificaron los elementos para instrumentar un sistema de vigilancia integral que mejore el uso de antibióticos y la valoración de la resistencia bacteriana.OBJECTIVE: To identify the levels of antibiotic utilization and the resistance profiles of nosocomial bacteria, as well as the strategies to diminish resistance to antibiotics. MATERIAL AND METHODS: A descriptive, retrospective (1994-1995 study was conducted in six tertiary level hospitals in Mexico City. RESULTS: A total of 86% antibiotic resistance was observed in these hospitals. The overall consumption of antibiotics per hospital ranged between 44 and 195 Defined Daily Doses/100 day-beds. CONCLUSIONS: We identified the components to frame an integral surveillance system aimed at improving the use of antibiotics and the quality of the bacterial resistance assessment in these hospitals.

  15. Perdurabilidad de la efectividad de la combinación penicilina-estreptomicina en la reducción de la carga bacteriana del semen de toro congelado en pastillas (Durability of the effectiveness of the penicillin-streptomycin combination in the reduction of the bacterial content of frozen bulls semen in concentrated pellet form

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    Luis O. Alba Gómez

    2005-07-01

    Full Text Available Se investigaron por bacteriología general 206 muestras de semen fresco, 133 de semen diluido y congelado en forma de pastillas con adición de penicilina-estreptomicina y 33 sin antibióticos, de diferentes toros de inseminación artificial clínicamente sanos. El resumen de los aislamientos agrupados según las especies bacterianas reveló que las especies más frecuentemente aisladas en muestras de semen fresco fueron E. coli (50,6%, otras enterobacterias (27,7%, Staphylococcus coag. neg. (26,2% y S. aureus (17,5%. En el semen congelado sin antibióticos y congelado con antibióticos estas bacterias fueron igualmente las predominantes. Se observó disminución de la frecuencia de aislamientos en las muestras de semen congelado sin antibióticos (78,8% que se hizo más notable en las muestras con antibióticos (18,8%, diferencias estadísticamente significativas

  16. Colonização e translocação bacteriana orofaríngea, gástrica e traqueal em crianças submetidas à ventilação pulmonar mecânica Colonización y translocación bacteriana orofaríngea, gástrica y traqueal en niños sometidos a ventilación pulmonar mecánica Oropharyngeal colonization, and gastric and tracheal bacterial translocation, in children experiencing mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Denise Miyuki Kusahara

    2012-01-01

    Full Text Available OBJETIVO: Descrever o padrão de colonização e translocação bacteriana orofaríngea, gástrica e traqueal em crianças submetidas à ventilação pulmonar mecânica. MÉTODOS: Estudo descritivo, realizado em uma Unidade de Cuidados Intensivos Pediátricos. Admitiram-se no estudo 30 crianças, sendo analisadas 216 culturas seriadas de secreção orofaríngea, gástrica e traqueal. Características microbiológicas, demográficas, clínicas, e terapêuticas foram avaliadas. RESULTADOS: Houve predominância de crianças portadoras de doenças crônicas, que fizeram uso de antibióticos, sedativos e protetores gástricos, submetidas à sondagem gástrica. Houve aumento no número de crianças colonizadas por patógenos durante a internação e predomínio das espécies: Enterobacter spp, K.pneumoniae, P.aeruginosa, A. baumanii e S.aureus. A maioria das crianças (80,0% sofreu translocação orofaríngea durante a internação na UCIP. CONCLUSÃO: Crianças criticamente enfermas podem representar grupo de pacientes com risco aumentado para colonização e translocação bacteriana predominantemente da região orofaríngea para a traquéia.OBJETIVO: Describir el patrón de colonización y translocación bacteriana orofaríngea, gástrica y traqueal en niños sometidos a ventilación pulmonar mecánica. MÉTODOS: Estudio descriptivo, realizado en una Unidad de Cuidados Intensivos Pediátricos. Se admitieron en el estudio a 30 niños, siendo analizados 216 cultivos seriados de secreción orofaríngea, gástrica y traqueal. Fueron evaluadas características microbiológicas, demográficas, clínicas, y terapéuticas. RESULTADOS: Hubo predominio de niños portadores de enfermedades crónicas, que hicieron uso de antibióticos, sedantes y protectores gástricos, sometidos a sondaje gástrico. Hubo aumento en el número de niños colonizados por patógenos durante el internamiento y predominio de las especies: Enterobacter spp, K.pneumoniae, P

  17. Endoftalmites bacterianas com culturas positivas: uma revisão de 6 anos Culture proven bacterial endophthalmitis: a 6-year review

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    Paulo José Martins Bispo

    2008-10-01

    Full Text Available OBJETIVO: Determinar a distribuição dos microrganismos isolados de pacientes com endoftalmite bacteriana e sua sensibilidade a antimicrobianos. MÉTODOS: Foram analisados retrospectivamente os dados clínicos e microbiológicos dos pacientes com hipótese diagnóstica de endoftalmite e cultura bacteriana positiva, atendidos no Departamento de Oftalmologia da UNIFESP de 1º de janeiro de 2000 a 31 de dezembro de 2005. RESULTADOS: De 451 pacientes, 153 (33,9% apresentaram cultura bacteriana positiva. Foram isolados 155 microrganismos, sendo 79,35% gram-positivos e 20,65% gram-negativos. Os Staphylococcus coagulase-negativos (SCoN (41,94% foram os mais freqüentemente isolados. A sensibilidade aos antimicrobianos entre os gram-negativos foi: amicacina 87,10%, tobramicina 80,65%, ciprofloxacina 96,67%, levofloxacina, gatifloxacina e moxifloxacina 100%, ceftazidima 85%, e gentamicina 80,65%. A sensibilidade à vancomicina entre os gram-positivos foi de 100%. S. aureus e SCoN apresentaram 83,33% de sensibilidade à oxacilina, 89,61% à ciprofloxacina e 100% à gatifloxacina e moxifloxacina. A forma de aquisição predominante foi a pós-operatória (60,65%. CONCLUSÃO: Observamos baixa sensibilidade da cultura para o diagnóstico etiológico das endoftalmites. Uma terapia antimicrobiana ou profilaxia empírica deve ser ativa contra os microrganismos gram-positivos, particularmente contra estafilococos. Estudos de vigilância de resistência bacteriana são importantes para adequação desses esquemas.PURPOSE: To assess the distribution of microorganisms isolated from patients with bacterial endophthalmitis and their antimicrobial susceptibility. METHODS: Retrospective analysis of medical and microbiological records of patients with suspected diagnosis of endophthalmitis and bacterial culture-proven at the Department of Ophthalmology, UNIFESP, between January 1 2000 and December 31 2005. RESULTS: 153 (33.9% of 451 patients showed positive bacterial

  18. Dinâmica das populações bacterianas em solos de Cerrados Dynamic of bacterial populations from Cerrado soils

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    João Carlos Pereira

    1999-05-01

    Full Text Available Nos ambientes tropicais, os Cerrados destacam-se pelo seu potencial agrícola. Apesar das funções dos microrganismos no crescimento das plantas e na produtividade das culturas, existem poucas informações dos efeitos resultantes do manejo do solo, na ecologia microbiana. Neste estudo, foram avaliados os efeitos das condições ambientais e das práticas agrícolas sobre as populações bacterianas. As densidades das populações em solos com vegetação nativa foram variáveis e diferenciadas. Em Sete Lagoas, MG, as populações de actinomicetos variaram de 1,7 a 50 X 10(4 UFC/g de solo seco, enquanto em Planaltina as densidades das populações bacterianas em solo com primeiro e segundo ano de cultivo de soja foram semelhantes, mas superiores ao solo com vegetação nativa. A utilização agrícola deste solo não resultou em desequilíbrios acentuados das populações de actinomicetos provenientes de esporos e hifas. As relações esporos/hifas variaram de 1,1 a 5,8. Na rizosfera da soja, os coeficientes de correlação entre as populações de actinomicetos com as demais populações bacterianas foram significativos. Os resultados evidenciam que as práticas agrícolas utilizadas na introdução da cultura da soja em solos de Cerrados pode influenciar o equilíbrio das populações na comunidade bacteriana.Among tropical environments, Cerrados stand out because of its agriculture potencial. Although microorganisms play an important role on soil sustainability and crop production, few information is available on the effects of soil management systems on Cerrado's microbial ecology. In this study the effects of environmental conditions and soil management practices on bacterial populations were evaluated. Bacterial population densities in soil under native vegetation were variable and diferentiated. Actinomycetes densities varied from 1.7 to 50 X 10(4 CFU/g dry soil in Sete Lagoas region, Brazil, whereas bacterial populations in both the

  19. ADN bacteriano en pacientes con cirrosis y ascitis estéril: Papel como marcador de translocación bacteriana y herramienta pronóstica Bacterial DNA in patients with cirrhosis ans sterile ascites: Its role as a marker of bacterial translocation and prognosis tool

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    J. M. González-Navajas

    2007-10-01

    Full Text Available Durante la última década hemos presenciado un aumento de la cantidad de datos relativos a la presencia de translocación bacteriana en los modelos experimentales de cirrosis. Sin embargo, los estudios clínicos se han visto limitados por la falta de métodos no invasivos para estudiar dicho fenómeno. En los últimos años, las investigaciones realizadas en nuestro laboratorio se han centrado en la detección del ADN bacteriano en el suero y el líquido ascítico de los pacientes con cirrosis y ascitis estéril, y en las implicaciones clínicas que ello conlleva. Al principio, gracias a un método basado en la reacción en cadena de la polimerasa (PCR y el secuenciamiento automatizado de nucleótidos, pudimos detectar e identificar la presencia de fragmentos de ADN bacteriano en dichos pacientes con ascitis no neutrocítica y con cultivo negativo. Desde entonces hemos acumulado una serie de datos que indican que la presencia de ADN bacteriano podría desempeñar un papel importante no sólo como marcador de translocación bacteriana, sino también como factor pronóstico a corto plazo. Expondremos aquí el pasado, el presente y el futuro de esta línea de investigación.During the last decade, we have witnessed an increase in the amount of data related with the presence of bacterial translocation in experimental models of cirrhosis. However, clinical studies have been limited by the lack of non-invasive methods to study this phenomenon. Over the past years, the research developed in our laboratory has been focused on the detection of bacterial DNA in serum and ascitic fluid of patients with cirrhosis and sterile ascites, the clinical and immunological implications of such finding. Initially, by means of a polymerase chain reaction (PCR-based method and automated nucleotide sequencing, we were able to detect and identify the presence of fragments of bacterial DNA in the mentioned patients with culture-negative, non-neutrocytic ascites. Since

  20. The putrescine biosynthesis pathway in Lactococcus lactis is transcriptionally regulated by carbon catabolic repression, mediated by CcpA.

    Science.gov (United States)

    Linares, Daniel M; del Río, Beatriz; Ladero, Victor; Redruello, Begoña; Martín, María Cruz; Fernández, María; Alvarez, Miguel A

    2013-07-01

    Lactococcus lactis is the lactic acid bacterium most widely used by the dairy industry as a starter for the manufacture of fermented products such as cheese and buttermilk. However, some strains produce putrescine from agmatine via the agmatine deiminase (AGDI) pathway. The proteins involved in this pathway, including those necessary for agmatine uptake and conversion into putrescine, are encoded by the aguB, aguD, aguA and aguC genes, which together form an operon. This paper reports the mechanism of regulation of putrescine biosynthesis in L. lactis. It is shown that the aguBDAC operon, which contains a cre site at the promoter of aguB (the first gene of the operon), is transcriptionally regulated by carbon catabolic repression (CCR) mediated by the catabolite control protein CcpA.

  1. A Computational Study of Amensalistic Control of Listeria monocytogenes by Lactococcus lactis under Nutrient Rich Conditions in a Chemostat Setting

    Directory of Open Access Journals (Sweden)

    Hassan Khassehkhan

    2016-09-01

    Full Text Available We study a previously introduced mathematical model of amensalistic control of the foodborne pathogen Listeria monocytogenes by the generally regarded as safe lactic acid bacteria Lactococcus lactis in a chemostat setting under nutrient rich growth conditions. The control agent produces lactic acids and thus affects pH in the environment such that it becomes detrimental to the pathogen while it is much more tolerant to these self-inflicted environmental changes itself. The mathematical model consists of five nonlinear ordinary differential equations for both bacterial species, the concentration of lactic acids, the pH and malate. The model is algebraically too involved to allow a comprehensive, rigorous qualitative analysis. Therefore, we conduct a computational study. Our results imply that depending on the growth characteristics of the medium in which the bacteria are cultured, the pathogen can survive in an intermediate flow regime but will be eradicated for slower flow rates and washed out for higher flow rates.

  2. Identification and characterization of the alpha-acetolactate synthase gene from Lactococcus lactis subsp. lactis biovar diacetylactis.

    Science.gov (United States)

    Marugg, J D; Goelling, D; Stahl, U; Ledeboer, A M; Toonen, M Y; Verhue, W M; Verrips, C T

    1994-01-01

    The conversion of 3-13C-labelled pyruvate in an acetoin-producing clone from a Lactococcus lactis subsp. lactis biovar diacetylactis strain DSM 20384 plasmid bank in Escherichia coli was studied by 13C nuclear magnetic resonance analysis. The results showed that alpha-acetolactate was the first metabolic product formed from pyruvate, whereas acetoin appeared at a much slower rate and reached only low concentrations. This alpha-acetolactate production shows that the cells express the gene for alpha-acetolactate synthase (als). Nucleotide sequence analysis identified an open reading frame encoding a protein of 554 amino acids. The deduced amino acid sequence exhibits extensive similarities to those of known alpha-acetolactate synthases from both prokaryotes and eukaryotes. The als gene is expressed on a monocistronic transcriptional unit, which is transcribed from a promoter located just upstream of the coding region. Images PMID:8017926

  3. Draft Genome Sequence of Human-Pathogenic Lactococcus garvieae LG-ilsanpaik-gs201105 That Caused Acute Acalculous Cholecystitis.

    Science.gov (United States)

    Kim, Ji Hyung; Kang, Do-Hyung; Park, Se Chang

    2015-06-04

    Lactococcus garvieae, which is generally known as a marine and freshwater fish pathogen, is now considered to be an emerging zoonotic pathogen in both human and veterinary medicine. In recent years, we have reported the infection of L. garvieae LG-ilsanpaik-gs201105 in the gallbladder of an old fisherman. In this study, we present the draft genome sequence of L. garvieae LG-ilsanpaik-gs201105, with a total genome size of 1,960,261 bp in 53 contigs and a 38.1% average G+C content. Interestingly, the capsule gene cluster, which was known as one of the crucial virulence factors in L. garvieae, was not detected in our isolate. This is the first genome sequence of human-pathogenic L. garvieae, which caused acute acalculous cholecystitis.

  4. Microencapsulation of probiotics in hydrogel particles: enhancing Lactococcus lactis subsp. cremoris LM0230 viability using calcium alginate beads.

    Science.gov (United States)

    Yeung, Timothy W; Arroyo-Maya, Izlia J; McClements, David J; Sela, David A

    2016-04-01

    Probiotics are beneficial microbes often added to food products to enhance the health and wellness of consumers. A major limitation to producing efficacious functional foods containing probiotic cells is their tendency to lose viability during storage and gastrointestinal transit. In this study, the impact of encapsulating probiotics within food-grade hydrogel particles to mitigate sensitivity to environmental stresses was examined. Confocal fluorescence microscopy confirmed that Lactococcus lactis were trapped within calcium alginate beads formed by dripping a probiotic-alginate mixture into a calcium solution. Encapsulation improved the viability of the probiotics during aerobic storage: after seven days, less than a two-log reduction was observed in encapsulated cells stored at room temperature, demonstrating that a high concentration of cells survived relative to non-encapsulated bacteria. These hydrogel beads may have applications for improving the stability and efficacy of probiotics in functional foods.

  5. Expression of mptC of Listeria monocytogenes induces sensitivity to class IIa bacteriocins in Lactococcus lactis.

    Science.gov (United States)

    Ramnath, Manilduth; Arous, Safia; Gravesen, Anne; Hastings, John W; Héchard, Yann

    2004-08-01

    Sensitivity to class IIa bacteriocins from lactic acid bacteria was recently associated with the mannose phosphotransferase system (PTS) permease, in Listeria monocytogenes. To assess the involvement of this protein complex in class IIa bacteriocin activity, the mptACD operon, encoding, was heterologously expressed in an insensitive species, namely Lactococcus lactis, using the NICE double plasmid system. Upon induction of the cloned operon, the recombinant Lc. lactis became sensitive to leucocin A. Pediocin PA-1 and enterocin A also showed inhibitory activity against Lc. lactis cultures expressing mptACD. Furthermore, the role of the three genes of the mptACD operon was investigated. Derivative plasmids containing various combinations of these three genes were made from the parental mptACD plasmid by divergent PCR. The results showed that expression of mptC alone is sufficient to confer sensitivity to class IIa bacteriocins in Lc. lactis.

  6. The PurR regulon in Lactococcus lactis – transcriptional regulation of the purine nucleotide metabolism and translational machinery

    DEFF Research Database (Denmark)

    Jendresen, Christian Bille; Martinussen, Jan; Kilstrup, Mogens

    2012-01-01

    Purine nucleotides are either synthesized de novo from 5-phosphoribosyl-1-pyrophosphate (PRPP) or salvaged from the environment. In Lactococcus lactis, transcription of the de novo synthesis operons, purCSQLF and purDEK, has genetically been shown to be activated by the PurR protein when bound to......-related functions. Of special interest is the presence of PurBox motifs in rrn promoters, suggesting a novel connection between nucleotide availability and the translational machinery........ This suggests that binding of the PurR protein to the PurBox takes over the role of the -35 sequence. The study has expanded the PurR regulon to include promoters in nucleotide metabolism, C(1) compound metabolism, phosphonate transport, pyrophosphatase activity, (p)ppGpp metabolism, and translation...

  7. Eficiência de uma fitase bacteriana na liberação de fósforo fítico em dietas de frangos de corte

    Directory of Open Access Journals (Sweden)

    R. Pereira

    2012-02-01

    Full Text Available Foi avaliada a eficiência de uma fitase (FT bacteriana na liberação de fósforo fítico utilizando-se curvas de calibração para características ósseas e de desempenho em frangos de corte. O delineamento experimental foi inteiramente ao acaso, com seis tratamentos e seis repetições até 28 dias de idade. O tratamento-controle foi uma dieta à base de milho e farelo de soja deficiente em fósforo (P. Dois tratamentos corresponderam às dietas basais acrescidas de P suplementar, 0,05% e 0,10%, e os outros à dieta basal com 66, 99 e 131 FTU/kg de ração. A curva padrão é definida pelo efeito da adição de P suplementar consumido sobre características ósseas e de desempenho, e os resultados dos tratamentos com fitase são confrontados com a curva para cálculo de P liberado. A adição de P suplementar influenciou o ganho de peso, o peso vivo e o consumo de ração de forma quadrática, bem como miligramas de cinzas ósseas de forma linear. A curva padrão adotada foi da variável miligramas de cinzas ósseas, pois a resposta linear melhor descreve a curva. As inclusões de 66, 99 e 131 FTU/kg liberaram, respectivamente, 0,048%, 0,049% e 0,062% de P. A fitase bacteriana é eficiente na liberação de fósforo fítico e possui viabilidade econômica.

  8. Avaliação e acompanhamento audiológico após meningite bacteriana Audiological assessment and follow-up post bacterial meningitis

    Directory of Open Access Journals (Sweden)

    MARIA INÊS VIEIRA COUTO

    1999-09-01

    Full Text Available A deficiência auditiva é uma das sequelas da meningite bacteriana que ocorre com maior frequência em crianças. Este estudo descreve o perfil audiológico (periférico e central de crianças internadas com diagnóstico de meningite bacteriana. Nas 89 crianças que compareceram ao seguimento audiológico após a alta hospitalar e foram submetidas aos testes audiológicos, os resultados evidenciaram que 85,4% apresentaram acuidade auditiva normal em ambas orelhas, 10,1% apresentaram deficiência auditiva neurossensorial bilateral e 4,5% apresentaram deficiência auditiva neurossensorial unilateral. Nos testes que avaliaram as habilidades de processamento auditivo, os resultados mostraram que 10% dessas crianças apresentaram alteração no desempenho de localização auditiva e de reconhecimento de sentenças com mensagem competitiva ipsilateral.Hearing loss is the more frequent sequel of bacterial meningitis in children. This study describes the audiological profile (peripheric and central of 89 children admitted to the hospital wards with the diagnosis of bacterial meningitis. Those children attended audiological follow up, after their hospital descharge, and were submitted to audiological tests. The results showed that 85.4% among them presented normal hearing in both ears 10.1% presented bilateral neurosensorial hearing loss and 4.5% presented unilateral neurosensorial hearing loss. The results from the auditory processing skills assessment showed that 10% of those children presented auditory localization and recognition of sentences with competitive messages (Paediatric Sentences Identification - ipsilateral disorders.

  9. Clinical and laboratorial characteristics of bacterial meningitis in children Características clínicas e laboratoriais de meningites bacterianas em crianças

    Directory of Open Access Journals (Sweden)

    Rita Lucena

    1996-12-01

    Full Text Available Data from the records of 528 children under 15 years old with diagnosis of acute bacterial meningitis, admitted at the Hospital Couto Maia between 1990 and 1992 were analyzed. Bacterial meningitis was more frequent in children under the age of 1 year (37.8%. The most common etiologic agent was H. influenzae (42.2%. The global letality was 20.9%. Individual predictors of poor outcome were: absence of the "classic triad", CSF cell count under 1000 /mm³, age under 2 years, presence of seizures, depressed sensorium, and S. pneumoniae as causal agent.Foram analisados dados de prontuário de 528 crianças com faixa etária entre 1 mês e 15 anos e diagnóstico de meningite bacteriana aguda, admitidas no Hospital Couto Maia entre 1990 e 1992. Meningite bacteriana foi mais frequente em crianças com idade inferior a 1 ano (37,8%. O agente etiológico mais comum foi H. influenzae (42,2%. A letalidade global foi 20,9% e os fatores preditivos de pior prognóstico foram: ausência da "tríade clássica" (febre, vômitos e rigidez de nuca, celularidade do líquido cefalorraquidiano inferior a 1000 /mm³, idade inferior a 2 anos, presença de convulsões, alteração do nível de consciência e S. pneumoniae como agente causal.

  10. Relación placa bacteriana y caries en un grupo de niños escolarizados entre 5 y 14 años de la población de la Boquilla - Cartagena en el año 2004-1

    Directory of Open Access Journals (Sweden)

    Lizelia Alfaro Zolá

    2013-10-01

    Full Text Available ResumenObjetivo: Describir la ocurrencia de placa bacteriana en las superficies dentales y relacionarla con el tipo de lesión de caries que se presenta en niños escolares de 5 a 14 años de la Boquilla - Cartagena. Materiales y Métodos: Se realizó un estudio de corte transversal, en el cual se seleccionó una muestra de 89 niños escolares de la población de la Boquilla a través de un muestreo aleatorio sistemático, a quienes se les evaluó el estado de higiene oral mediante el índice de placa comunitario de Corchuelo modificado y el índice de caries superficial con criterios de diagnóstico Ekstrand. Resultados: La superficie con lesiones de caries de mayor frecuencia fue la oclusal, presentándose un mayor numero de lesiones detenidas, seguido en palatino por las lesiones precavitacionales, a diferencia de las superficies vestibular y lingual donde se encontraron un mayor número de superficies sanas. En todas las superficies evaluadas predominó la presencia de placa bacteriana independientemente de la presencia de caries y no se encontró una relación estadísticamente significativa entre estas dos variables. Conclusiones: La alta frecuencia de placa bacteriana en las superficies dentarias nos mostró el deficiente estado de higiene oral de la población, sin embargo, sigue en duda la pertinencia de los índices de placa para la predicción de la caries debido a que no se encontró relación estadística. (Duazary 2007; 2: 119 - 126AbstractObjectives: describe the presence of dental plaque in healthy in the dental surfaces and relate it with the type of lesion of caries in children between 5 and 14 years of age in the village of la Boquilla- Cartagena. Material and Methods: This is study transversal, in a universe of 89 scholar children in the village of la Boquilla, 60 of these were chosen through a systematic aleatory sampling. They were evaluated to establish their status of oral hygiene using the modified

  11. Consideraciones sobre el empleo de antisueros somáticos en la clasificación por serotipos de cepas de Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Aniel Moya

    2007-07-01

    Full Text Available El lipopolisacárido (LPS de bacterias gramnegativas se emplea en el desarrollo de candidatos vacunales, como antígeno expuesto en la preparación o formando parte de esta para aumentar su poder inmunogénico. Sin embargo, esta estructura química de la membrana externa puede ser también utilizada para clasificar bacterias. Según el LPS, presente en la membrana externa bacteriana, Pseudomonas aeruginosa se puede clasificar en 20 tipos somáticos diferentes, clasificación muy útil para estudios epidemiológicos. P. aeruginosa expone sus LPS en la membrana de forma estable, pero ocurren cambios en el fenotipo del LPS bacteriano durante la infección, sucesos que dificultan su clasificación. En estos momentos, los estudios que se desarrollan en el Instituto Finlay necesitan del empleo de tecnologías modernas de clasificación y del diagnóstico molecular para poder establecer patrones más precisos de expresión de los LPS por métodos que junto a los ya existentes permitan diferenciar cepas bacterianas de la misma especie en cualquier tipo de infección.

  12. Ação do biofertilizante Agrobio sobre a mancha-bacteriana e desenvolvimento de mudas de pimentão Effect of the Agrobio biofertilizer on the bacterial spot and the development of bell pepper transplants

    Directory of Open Access Journals (Sweden)

    Cláudia S.R. Deleito

    2005-03-01

    Full Text Available O biofertilizante Agrobio é produzido a partir de esterco bovino fresco, água, melaço e sais minerais em recipientes abertos. Tem sido largamente utilizado por agricultores orgânicos e convencionais no estado do Rio de Janeiro, ao qual atribuem efeito nutricional e de controle de doenças. O presente trabalho foi feito com o objetivo de elucidar e quantificar aspectos relativos ao efeito do Agrobio sobre o controle da mancha-bacteriana e desenvolvimento de mudas de pimentão, em condições de casa-de-vegetação. Utilizaram-se as cultivares Cascadura Ikeda e Cascadura Itaipu e os tratamentos à base de Agrobio, diluído a 5% em água destilada, previamente submetido aos seguintes preparos: original; autoclavado (120ºC/20 min; filtrado em millipore (0,22 mm de diâmetro e a fração retida no filtro millipore após a filtragem do produto, e dois modos de aplicação (foliar e no substrato e, como testemunhas oxitetraciclina + sulfato de estreptomicina (0,8 g L-1, oxicloreto de cobre (2,4 g L-1 e água. O Agrobio original e filtrado em aplicação foliar, em geral, proporcionaram melhor controle da doença e maior desenvolvimento das mudas que o Agrobio autoclavado ou a sua fração retida em aplicação via substrato. O controle da doença pelo Agrobio, foi inferior ao proporcionado pelos produtos comerciais à base de oxicloreto de cobre e de oxitetraciclina + sulfato de estreptomicina, porém foi estatisticamente superior à testemunha água. O Agrobio favoreceu, porém, o desenvolvimento vegetativo das mudas, o aumento da área foliar, a maior retenção das folhas infectadas e a população de Bacillus spp.The Agrobio biofertilizer is prepared from fresh cattle manure, water, molasses and minerals in open containers. This product has been widely used by organic and conventional farmers of the Rio de Janeiro State to control several plant pathogens. This research aimed to elucidate and quantify some of the aspects related to the

  13. Partial characterization of an rpoD-like gene of Lactococcus lactis subsp. lactis ML3 with a polymerase chain reaction-based approach.

    Science.gov (United States)

    Gansel, X; Dutreix, M; Hartke, A; Boutibonnes, P; Auffray, Y

    1993-11-01

    With degenerated oligonucleotide primers for conserved regions of bacterial sigma factor proteins, a 117-bp internal DNA fragment of an rpoD-like gene of Lactococcus lactis subsp. lactis ML3 was amplified by the polymerase chain reaction (PCR). The DNA sequence of this PCR product was determined by cycle sequencing, and the deduced amino acid sequence of this internal fragment showed an extensive homology with the known sigma factor sequences from six other microorganisms and present a 13-amino acid region corresponding to the typical "RpoD box" of primary sigma factors. This PCR product was used as a probe to specifically detect sigma homologs in Pediococcus acidilactici, Leuconostoc lactis, Lactobacillus helveticus, Lactobacillus acidophilus, Enterococcus faecalis, Streptococcus thermophilus, and Lactococcus lactis subsp. cremoris. These data are consistent with the existence of a high similarity between the primary sigma factors from diverse Gram-positive microorganisms.

  14. Ototoxicidad por medicamentos

    OpenAIRE

    Mercado M,Víctor; Burgos S,Rodolfo; Muñoz V,Claudio

    2007-01-01

    Se define ototoxicidad a las perturbaciones transitorias o definitivas de la función auditiva, vestibular, o de las dos a la vez, inducidas por sustancias de uso terapéutico¹. Son muchos los trabajos de investigación que se han dedicado ha este tema quedando aun dudas por resolver debido a las complejas consecuencias donde está envuelto el daño cocleovestibular. El propósito de esta revisión, es presentar las últimas teorías que tratan de explicar desde el punto de vista de la farmacociónétic...

  15. Electrocardiografo por computadora

    OpenAIRE

    Tinoco Hernandez, Rosanna; Paredes Bejarano, Margarita; Romero Chaglia, Norman; Yapur Auad, Miguel Eduardo

    2009-01-01

    El presente trabajo trata sobrees el diseño y la implementación de un graficador de señales cardiacas por computadora, para lo cual diseñamos un circuito electrónico capaz de recibir la senal analógica proveniente de la actividad electrica del corazón , amplificarla, y luego convertirla en una señal digital para ser procesada por software y finalmente ser graficada, siendo posible así observar la señal cardiaca en el monitor de un computador como un tren de pulsos. Cabe destacar que par...

  16. La réponse au stress osmotique des bactéries lactiques Lactococcus lactis et Lactobacillus plantarum (mini-revue)

    OpenAIRE

    Romeo, Yves; Bouvier, Jean; Gutierrez, Claude

    2001-01-01

    International audience; Osmotic stress response of lactic acid bacteria Lactococcus lactis and Lactobacillus plantarum. In order to survive in a wide variety of environments, bacteria have evolved systems that protect themselves against environmental stress. Lactic acid bacteria grow in media where osmolarity is high and varies frequently and they must adjust their intracellular osmolarity in order to maintain the turgor pressure necessary for cell elongation. An osmotic upshock stops their g...

  17. Lytr, a phage-derived amidase is most effective in induced lysis of Lactococcus lactis compared with other lactococcal amidases and glucosaminidases

    NARCIS (Netherlands)

    Steen, Anton; van Schalkwijk, Saskia; Buist, Girbe; Twigt, Marja; Szeliga, Monika; Meijer, Wilco; Kuipers, Oscar P.; Kok, Jan; Hugenholtz, Jeroen

    2007-01-01

    In the genome of Lactococcus lactis IL1403 five genes encoding peptidoglycan hydrolases are present: four glucosaminidases (acmA, acmB, acmC and acmD) and an endopeptidase (yjgB). Genes for six prophage lysins have also been identified. The genes acmB, acmC, acmD, yjgB and the lysin lytR of prophage

  18. The ArcD1 and ArcD2 arginine/ornithine exchangers encoded in the arginine deiminase (ADI) pathway gene cluster of Lactococcus lactis

    NARCIS (Netherlands)

    Noens, Elke E E; Kaczmarek, Michał B; Żygo, Monika; Lolkema, Juke S

    2015-01-01

    The arginine deiminase pathway (ADI) gene cluster in Lactococcus lactis contains two copies of a gene encoding an L-arginine/L-ornithine exchanger, the arcD1 and arcD2 genes. The physiological function of ArcD1 and ArcD2 was studied by deleting the two genes. Deletion of arcD1 resulted in loss of th

  19. Formação de biofilme por Pseudomonas aeruginosa sobre aço inoxidável em contato com leite e seu controle por óleos essenciais

    Directory of Open Access Journals (Sweden)

    Nádia Nara BATISTA

    2014-01-01

    Full Text Available Objetivo: Avaliar a ação bacteriostática e bactericida de diferentes óleos essenciais sobre células planctônicas de Pseudomonas aeruginosa ATCC 27853, bem como verificar a ação sanitizante, dos óleos essenciais que apresentarem a menor Concentração Mínima Inibitória (CMI, sobre o biofilme formado por esta espécie, Material e Métodos: A ação bacteriostática foi realizada por meio da determinação das CMIs dos óleos de Zingiber officinale, Eugenia caryophyllus, Elettaria cardamomum, Citrus limon e Citrus reticulata v, tangerine, O tempo de morte bacteriana foi determinado utilizando-se as CMIs de cada óleo essencial submetidos a diferentes tempos de contato, O biofilme de P, aeruginosa foi desenvolvido em cupons de aço inoxidável AISI 304 dispostos em placa de Petri contendo leite tratado por Ultra Alta Temperatura (UAT, sendo incubado sob agitação de 70 rpm, a 37 °C/96 horas, Células aderidas foram removidas através de swabs e enumeradas por contagem em placas após submissão a diferentes tratamentos, Resultados: Todos os óleos essenciais apresentaram efeito bacteriostático, se destacando Z, officinale, E, caryophyllus e E, cardamomum, por apresentarem menor CMI, O tempo de morte de P, aeruginosa foi de 10 minutos quando utilizadas soluções a base de E, cardamomum e E, caryophyllus, No entanto, quando testados em biofilme, apenas E, caryophyllus eliminou as células bacterianas viáveis de P, aeruginosa, Conclusão: E, caryophyllus é uma nova alternativa para o controle do biofilme de P, aeruginosa na indústria de alimentos, pois, além de sua alta atividade antimicrobiana, é um composto natural, o que atende as exigências do mercado consumidor.

  20. Extracellular secretion of a maltogenic amylase from Lactobacillus gasseri ATCC33323 in Lactococcus lactis MG1363 and its application on the production of branched maltooligosaccharides.

    Science.gov (United States)

    Cho, Mee-Hyun; Park, Sang-Eun; Lee, Myung-Hun; Ha, Suk-Jin; Kim, Hae-Yeong; Kim, Myo-Jeong; Lee, Sung-Joon; Madsen, Søren M; Park, Cheon-Seok

    2007-09-01

    A maltogenic amylase gene from Lactobacillus gasseri ATCC33323 (LGMA) was expressed in Lactococcus lactis MG1363 using the P170 expression system. The successful production of recombinant LGMA (rLGMA) was confirmed by the catalytic activity of the enzyme in liquid and solid media. The N-terminal amino acid sequencing analysis of the rLGMA showed that it was Met-Gln-Leu-Ala-Ala-Leu-, which was the same as that of genuine protein, meaning the signal peptide was efficiently cleaved during secretion to the extracellular milieu. The optimal reaction temperature and pH of rLGMA (55 degrees C and pH 5, respectively) and enzymatic hydrolysis patterns on various substrates (beta-cyclodextrin, starch, and pullulan) supported that rLGMA was not only efficiently secreted from the Lactococcus lactis MG1363 but was also functionally active. Finally, the branched maltooligosaccharides were effectively produced from liquefied corn starch, by using rLGMA secreted from Lactococcus lactis, with a yield of 53.1%.