WorldWideScience

Sample records for bacteriana por lactococcus

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

    Directory of Open Access Journals (Sweden)

    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"

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

    OpenAIRE

    Andrés Zúñiga; Fabián Tobar-Tosse

    2015-01-01

    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 prot...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  5. 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 ...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. La nueva especie bacteriana descubierta por el SERIDA, "Pseudomonas asturiensis" es patógena en soja

    OpenAIRE

    González, A.J. (Ana); Fernández-Sanz, A.M. (Ana)

    2014-01-01

    Los daños producidos en un cultivo de soja forrajera nos han llevado a describir una nueva especie bacteriana a la que hemos denominado Pseudomonas asturiensis. La bacteria se ha encontrado en diferentes localidades de Asturias y en diferentes huéspedes que incluyen malas hierbas y será necesario ampliar su estudio para conocer su potencial peligrosidad para el campo astur.

  9. Estudio de los efectos causados por la introducción de sistemas de rizorremediación en las poblaciones bacterianas nativas de un suelo contaminado por PCBs

    OpenAIRE

    Aguirre de Cárcer, Daniel

    2014-01-01

    Los diferentes análisis llevados a cabo en este estudio sostienen que la comunidad bacteriana de la rizosfera, que evolucionó de la población nativa de un suelo con un historial de contaminación por bifenilos policlorados, durante el desarrollo de las raíces de Salix vimminalis, fue diferente de la comunidad parental tanto a niveles funcionales como estructurales. La rizosfera estuvo enriquecida en especies de Proteobacteria, y en genes de ISP altamente relacionados con el grupo de las bacte...

  10. Avaliação da resistência do eucalipto à murcha-bacteriana causada por Ralstonia solanacearum

    OpenAIRE

    Reginaldo Gonçalves Mafia; Acelino Couto Alfenas; Maria Alves Ferreira

    2014-01-01

    O plantio de clones de eucalipto resistentes constitui a principal estratégia para o controle de doenças no campo. Assim, este trabalho objetivou testar métodos de inoculação de Ralstonia solanacearum visando selecionar eucalipto resistente à murcha-bacteriana. Os métodos de inoculação foram selecionados em função da facilidade operacional e testados na avaliação de quatro clones (híbridos E. urophylla x E. grandis): i) aplicação de 5 mL de inóculo (10(8) ufc/mL) na região do coleto de mudas;...

  11. 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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  13. Pré-condicionamento isquêmico em diferentes tempos e seu efeito na translocação bacteriana induzida por isquemia e reperfusão intestinal em ratos

    Directory of Open Access Journals (Sweden)

    Aldo da Cunha Medeiros

    2013-02-01

    Full Text Available OBJETIVO: avaliar os efeitos de diferentes tempos de pré-condicionamento isquêmico(PCI intestinal sobre a translocação bacteriana (TB. MÉTODOS: Trinta ratos Wistar pesando 280±27g foram alocados em cinco grupos. No grupo IR (n=6, foi realizada laparotomia e a artéria mesentérica superior foi ocluída por microclampe atraumático por 30 minutos. Nos quatro grupos com pré-condicionamento (n=6 cada, antes dos 30 minutos de isquemia-reperfusão (I/R os ratos foram submetidos a PCI de dois, cinco, dez e 15 minutos e, em seguida, ao mesmo tempo de reperfusão. Vinte e quatro horas após, para avaliar se os tempos de pré-condicionamento influenciam o aparecimento de translocação bacteriana, amostras de linfonodos mesentéricos, fígado e baço foram coletadas em condições estéreis, para quantificação de unidades formadoras de colônias bacterianas por grama de tecido (UFC/g. Sangue foi coletado para dosagem de citocinas. RESULTADOS: No grupo I/R, o total de UFC/g em linfonodos mesentéricos, baço, fígado, bem como, a dosagem sérica de TNF-a, IL-1b e IL-6 foram significativamente maiores do que nos demais grupos (p<0,05. Pré-condicionamento de 15 minutos atenuou significativamente a BT e as citocinas séricas, comparando com os outros tempos de pré-condicionamento (p<0,05. CONCLUSÃO: Nossos dados sugerem o pré-condicionamento como fator-chave para reduzir translocação bacteriana em I/R intestinal. Numa escala de dois a 15 minutos, o melhor tempo de pré-condicionamento isquêmico para a atenuação da translocação bacteriana foi 15 minutos.

  14. 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

    Directory of Open Access Journals (Sweden)

    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

  15. 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

    Directory of Open Access Journals (Sweden)

    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.

  16. La necrosis bacteriana de la vid, causada por xylophilus ampelinus. Detección serológica, distribución en Aragón y sensibilidad varietal.

    OpenAIRE

    CAMBRA ALVAREZ, MIGUEL

    2011-01-01

    La necrosis bacteriana de la vid, causada por la bacteria de cuarentena Xylophilus ampelinus, es una enfermedad de difícil control químico y que ha causado en España importantes pérdidas económicas. Actualmente, es endémica en distintas zonas de Aragón y Galicia y se han identificado focos aislados en La Rioja. Ante la carencia de métodos sensibles y específicos de detección de esta bacteria que se puedan utilizar para el análisis rutinario, se ha puesto a punto un método de ex...

  17. 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

    Directory of Open Access Journals (Sweden)

    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.

  18. Monitoramento da atividade bacteriana de um sistema de lodos ativados Bardenpho por meio da respirometria Control of reaction sludg's system bacterian activity - Bardenpho through respirometry

    Directory of Open Access Journals (Sweden)

    Adriana Guimarães Costa

    2007-03-01

    Full Text Available Nos sistemas aeróbios de tratamento de águas residuárias, o oxigênio é um elemento fundamental para que a massa bacteriana possa metabolizar o material orgânico e oxidar compostos como a amônia. Para o acompanhamento desse processo pode ser utilizada a respirometria. Nesta pesquisa, os objetivos são: (1 avaliar a influência da interrupção da aeração sob a atividade das bactérias de sistemas do tipo Bardenpho; (2 estudar a influência do pH na capacidade oxidativa das bactérias nitrificantes; (3 conhecer a faixa de pH ideal para o desenvolvimento das bactérias nitrificantes; e (4 observar a confiabilidade da respirometria no monitoramento da atividade bacteriana. Pôde-se concluir que (1 a capacidade metabólica sofre uma redução gradual na medida em que se aplica um período mais longo sem aeração, (2 o pH influenciou diretamente a atividade das nitrificantes, de forma distinta para a oxidação a nitrito e na oxidação a nitrato, e (3 a respirometria foi uma ferramenta muito útil para avaliar a atividade bacteriana e os sistemas de lodo ativado.In the sewage water treatment aerobic systems oxygen is a fundamental element for the bacterial mass to be able to metabolize organic matter and oxidize compounds such as ammonia. Respirometry can be used in the follow-up of such process. The goals of this research are: (1 to assess the influence of interrupting aeration under Bardenpho-type systems bacterial activity; (2 to study on the influence of pH in the oxidative capacity of nitrifying bacteria; (3 to establish the ideal pH rate for developing nitrifying bacteria; (4 to observe the reliability of respirometry in monitoring the bacterial activity. The conclusions achieved were that (1 the metabolic capacity is gradually reduced as a longer period without aeration is applied, (2 the pH directly influenced the activity of nitrifying bacteria in a distinct manner for both nitrite and nitrate oxidation, and (3 respirometry was a

  19. Meningitis bacteriana Bacterial meningitis

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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

  1. Meningitis bacteriana Bacterial meningitis

    OpenAIRE

    Ana Teresa Alvarado Guevara; Lizzie Marie Castillo Solano

    2006-01-01

    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 pleoc...

  2. Meningites bacterianas recidivantes

    Directory of Open Access Journals (Sweden)

    Maria Valeriana L. Moura-Ribeiro

    1992-06-01

    Full Text Available O estudo das fístulas liquóricas, envolvendo anormalidades otorrinolaringológicas, deve se basear na procura da causa fundamental que leva às meningites recidivantes. As malformações congênitas, as anormalidades pós-traumáticas e pós-operatórias ou, ainda, associadas a doenças que envolvem ossos cranianos, constituem as causas básicas a serem pesquisadas. Os traumas cranianos podem resultar em fístula liquórica com possibilidade de meningites bacterianas de repetição.

  3. 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

    Directory of Open Access Journals (Sweden)

    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.

  4. 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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    DANESI Eliane Dalva Godoy; Wosiacki, Gilvan

    1998-01-01

    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 d...

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

    Directory of Open Access Journals (Sweden)

    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 .

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Producción de ácido láctico por una mezcla de lactococcus lactis y streptococcus salivarius en fermentaciones en discontinuo

    OpenAIRE

    Serna Cock, Liliana; Rodríguez de Stouvenel, Aida

    2006-01-01

    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...

  9. Las enfermedades periodontales como infecciones bacterianas

    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.

  10. Murcha bacteriana no estado do Amazonas, Brasil Bacterial wilt in Amazonas State, Brazil

    OpenAIRE

    ROSALEE A. COELHO NETTO; Bianca G. Pereira; Hiroshi Noda; Bernard Boher

    2004-01-01

    Durante 1998 e 2000, a incidência de murcha bacteriana causada por Ralstonia solanacearum foi registrada em 25 municípios do estado do Amazonas. A bactéria foi encontrada nas seguintes espécies vegetais: Capsicum annuum, C. chinense, C. frutescens, Cucumis sativus, Heliconia sp., Lycopersicon esculentum, Melanthera discoidea, Moringa oleifera, Musa sp., Solanum melongena, S. gilo, e S. nigrum. Em tomateiros (Lycopersicon esculentum), a murcha bacteriana estava presente em todos os plantios. E...

  11. 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

    Directory of Open Access Journals (Sweden)

    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

  12. Cambios en las comunidades bacterianas de suelo luego de una contaminación con hexadecano

    OpenAIRE

    Pucci, Graciela N.; Adrián J. Acuña; Natalia Y. Nohra; Oscar H. Pucci

    2012-01-01

    El presente trabajo informa sobre los cambios en la comunidad bacteriana de un suelo proveniente de una zona hidrocarburífera de Argentina. Los cambios se observaron en un ensayo de microcosmo el cual fue sometido a contaminación con hexadecano. La determinacion de hidrocarburos y los recuentos bacterianos fueron realizados semanalmente. Los cambios en la diversidad bacteriana se determinaron por la el análisis de los ácidos grasos de membrana (FAMEs); identificándose y cuantificándose por cr...

  13. Cambios en las comunidades bacterianas de suelo luego de una contaminación con hexadecano

    Directory of Open Access Journals (Sweden)

    Graciela N. Pucci

    2012-10-01

    Full Text Available El presente trabajo informa sobre los cambios en la comunidad bacteriana de un suelo proveniente de una zona hidrocarburífera de Argentina. Los cambios se observaron en un ensayo de microcosmo el cual fue sometido a contaminación con hexadecano. La determinacion de hidrocarburos y los recuentos bacterianos fueron realizados semanalmente. Los cambios en la diversidad bacteriana se determinaron por la el análisis de los ácidos grasos de membrana (FAMEs; identificándose y cuantificándose por cromatografía gaseosa utilizando los parámetros según MIDI. Se observó que la contaminación con hexadecano causa un disturbio en el suelo que conduce a un cambio en la estructura de la comunidad bacteriana.

  14. Antibióticos vs. resistencia bacteriana

    Directory of Open Access Journals (Sweden)

    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

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

    OpenAIRE

    Adriana M. Ombrella; Adriana Belmonte; Mónica G. Nogueras; Isabel Ruiz Abad; Emma G. Sutich; Dlugovitzky, Diana G.

    2006-01-01

    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 es...

  16. 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...

  17. 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...

  18. 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

    OpenAIRE

    Rodríguez de Stouvenel Aida; Serna Cock Liliana

    2005-01-01

    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...

  19. 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.

  20. 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.

  1. Fontes de silício no controle da mancha bacteriana (Xanthomonas spp. do tomateiro

    Directory of Open Access Journals (Sweden)

    Thaíssa Vitorino dos Anjos

    2014-12-01

    Full Text Available A mancha bacteriana do tomateiro causada por quatro espécies de Xanthomonas pode provocar perdas significativas na produção da cultura e a utilização do silício na proteção de plantas tende a reduzir a incidência de doenças. O objetivo do trabalho foi avaliar fontes de silício no controle da mancha bacteriana do tomateiro. Para a avaliação da inibição do crescimento bacteriano in vitro foram utilizados discos de papel de filtro esterilizados contendo 10 µL de silício coloidal ou silicato de potássio nas concentrações de 10, 30, 40 e 50 µg µL-1. Esses discos foram colocados sobre a bactéria cultivada em placas de Petri com meio de cultura, observando-se a formação de halos de inibição. Para avaliação da redução da severidade da mancha bacteriana do tomateiro em casa de vegetação, plantas de tomate foram pulverizadas com os produtos nas concentrações 10, 20, 30, 40 e 50 g L-1 e, após três dias, foi feita a inoculação por aspersão da suspensão bacteriana (109 UFC mL-1. Como testemunhas foram utilizadas plantas pulverizadas com água destilada ou inoculadas com a suspensão bacteriana. O silício coloidal não foi eficiente no controle de Xanthomonas spp. Concentrações de 30, 40 e 50 µg µL-1 de silicato de potássio inibiram o crescimento bacteriano in vitro e concentrações de 40 e 50 g L-1 reduziram o índice de doença da mancha bacteriana do tomateiro.

  2. Fontes de silício no controle da mancha bacteriana (Xanthomonas spp.) do tomateiro

    OpenAIRE

    Thaíssa Vitorino dos Anjos; Nilvanira Donizete Tebaldi; Lara Caroline Borges Moreira Mota; Lísias Coelho

    2014-01-01

    A mancha bacteriana do tomateiro causada por quatro espécies de Xanthomonas pode provocar perdas significativas na produção da cultura e a utilização do silício na proteção de plantas tende a reduzir a incidência de doenças. O objetivo do trabalho foi avaliar fontes de silício no controle da mancha bacteriana do tomateiro. Para a avaliação da inibição do crescimento bacteriano in vitro foram utilizados discos de papel de filtro esterilizados contendo 10 µL de silício coloidal ou silicato de p...

  3. 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...

  4. 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

  5. Infecção bacteriana no paciente cirrótico

    Directory of Open Access Journals (Sweden)

    Mattos Angelo A. de

    2003-01-01

    Full Text Available RACIONAL: Em torno de 30% dos pacientes com cirrose hepática apresentam infecção bacteriana na admissão hospitalar ou a desenvolvem durante a mesma. As infecções bacterianas são responsáveis por até 25% das mortes nesta população de pacientes. OBJETIVO: Avaliar a prevalência de infecção bacteriana em uma população de pacientes cirróticos internados em hospital geral, bem como correlacionar sua presença com a etiologia alcoólica da hepatopatia, com o grau de comprometimento da função hepática e com a presença de hemorragia digestiva alta. PACIENTES E MÉTODOS: Foram avaliadas retrospectivamente 541 internações hospitalares consecutivas em 426 pacientes com cirrose hepática, internados no período de 1992 a 2000. A média de idade destes pacientes foi de 50,5 anos (15-95, sendo 71,2% do sexo masculino. Etiologia alcoólica da hepatopatia esteve presente em 35,4% dos pacientes. Alta ou óbito do paciente no período da internação hospitalar foi considerado como principal desfecho. O nível de significância considerado na análise estatística foi de 5%. RESULTADOS: As infecções bacterianas ocorreram em 25% dos cirróticos (135 episódios. Destas, as mais freqüentes foram: a infecção do trato urinário em 31,1%, a peritonite bacteriana espontânea em 25,9% e a broncopneumonia em 25,2%. Ocorreu associação de infecção urinária e broncopneumonia em 3,7% e infecção de pele e tecido celular subcutâneo em 11,11%. Bacteremia sem foco definido ocorreu nos quatro casos restantes (2,9%. Houve associação da presença de infecção com a etiologia alcoólica da hepatopatia, com a classificação de Child-Pugh e com a ocorrência de hemorragia digestiva alta. A mortalidade hospitalar foi maior nos pacientes infectados (8,9%, estando a mesma associada ao grau de disfunção hepatocelular. CONCLUSÕES: A ocorrência de infecção bacteriana no paciente cirrótico hospitalizado é freqüente e correlaciona-se com a

  6. Adhesión bacteriana a biomateriales Bacterial adhesion to biomaterials

    Directory of Open Access Journals (Sweden)

    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.

  7. 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.

  8. Etiologia de meningites bacterianas em uma amostra da população de Salvador - Bahia

    Directory of Open Access Journals (Sweden)

    NASCIMENTO-CARVALHO CRISTIANA M. C.

    1998-01-01

    Full Text Available As meningites bacterianas constituem patologia importante na faixa etária pediátrica. Com o objetivo de conhecer a distribuição da etiologia desta patologia em uma amostra da população de Salvador, Bahia, foram analisados, retrospectivamente, 7000 exames de líquor, realizados entre setembro de 1988 e agosto de 1995, no laboratório de liquorologia da Fundação José Silveira. Foram selecionados 892 (12,7% exames realizados em pacientes menores de 16 anos e com suspeita de meningite; entre os 139 casos de meningite bacteriana, H. influenzae tipo b foi o agente mais frequente (26,0%, ocorrendo em 100% das vezes em menores de 5 anos. Observou-se tendência na queda do número de casos de meningite por H. influenzae tipo b a partir de 1992. Questiona-se se este fato decorre do uso da vacina anti-H. influenzae tipo b nesta amostra da população.

  9. 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.

  10. Lactococcus lactis - a diploid bacterium

    DEFF Research Database (Denmark)

    Michelsen, Ole; Hansen, Flemming G.; Jensen, Peter Ruhdal

    In contrast to higher eukaryotes, bacteria are haploid, i.e. they store their genetic information in a single chromosome, which is then duplicated during the cell cycle. If the growth rate is sufficiently low, the bacterium is born with only a single copy of the chromosome, which gets duplicated...... before the bacterium divides. Fast-growing bacteria have overlapping rounds of replication, and can contain DNA corresponding to more than four genome equivalents. However, the terminus region of the chromosome is still present in just one copy after division, and is not duplicated until right before...... the next division. Thus, the regions of the chromosome that are the last to be replicated are haploid even in fast-growing bacteria. In contrast to this general rule for bacteria, we found that Lactococcus lactis, a bacterium which has been exploited for thousands of years for the production of fermented...

  11. 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.

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

    OpenAIRE

    Edna Strauss; José Pedro Aerosa

    2004-01-01

    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-bi...

  13. 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.

  14. Biossíntese de celulose bacteriana a partir de resíduos industriais

    OpenAIRE

    Gomes, Fábio Pedro Almeida

    2011-01-01

    A celulose bacteriana (CB) é um biopolímero que devido às suas propriedades estruturais e mecânicas tem uma vasta gama de aplicações em diferentes áreas. Este biopolímero pode ser produzido por algumas bactérias, nomeadamente as pertencentes ao género Gluconacetobacter. No entanto, devido ao custo do meio de cultura a produção de CB a nível industrial tem pouca viabilidade económica. O trabalho realizado teve como objectivo a utilização de diferentes resíduos da Industria Agro-Alimentar para ...

  15. Efectos de los antioxidantes y la fagocitosis bacteriana sobre la apoptosis de los neutrófilos

    OpenAIRE

    Bonilla del Río, Zuriñe

    2013-01-01

    La fagocitosis bacteriana por los neutrófilos retrasa la apoptosis de los mismos cuando la relación bacteria/neutrófilo es baja, y la acelera cuando dicha relación es alta. Las bacterias también inducen en los neutrófilos la producción de sustancias reactivas de oxígeno que incrementarían su apoptosis, y de citoquinas que podrían retrasarla. El antioxidante DPI (difenileniodonio), inhibidor específico de la NADPH oxidasa de los neutrófilos, podría modificar la apoptosis de...

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

    OpenAIRE

    Marcia M. Rojas; Odette González; Nidia Rojas; Mayra Heydrich

    2007-01-01

    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 az...

  17. 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.

  18. 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

  19. Glutathione protects Lactococcus lactis against oxidative stress

    NARCIS (Netherlands)

    Li, Y.; Hugenholtz, J.; Abee, T.; Molenaar, D.

    2003-01-01

    Glutathione was found in several dairy Lactococcus lactis strains grown in M17 medium. None of these strains was able to synthesize glutathione. In chemically defined medium, L. lactis subsp. cremoris strain SK11 was able to accumulate up to similar to60 mM glutathione when this compound was added t

  20. 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

  1. 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

  2. Dynamics of pyruvate metabolism in Lactococcus lactis

    DEFF Research Database (Denmark)

    Melchiorsen, Claus Rix; Jensen, Niels B.S.; Christensen, Bjarke;

    2001-01-01

    The pyruvate metabolism in the lactic acid bacterium Lactococcus lactis was studied in anaerobic cultures under transient conditions. During growth of L. lactis in continuous culture at high dilution rate, homolactic product formation was observed, i.e., lactate was produced as the major end prod...

  3. Permeabilidad hidráulica e hinchamiento de membranas de celulosa bacteriana

    Directory of Open Access Journals (Sweden)

    L.A. Caicedo

    2006-01-01

    Full Text Available El grado de hinchamiento y la permeabilidad hidráulica fueron evaluados en membranas de celulosa bacteriana obtenida por cultivo estático de Acetobacter sp. por tres y nueve días, en medio con glucosa y extracto de levadura. Las pruebas de hinchamiento fueron realizadas en disoluciones etanólicas de 0, 10, 50 y 95 % (v/v de etanol, por 24 h a (18 ± 1 °C . El grado de hinchamiento definido como la relación entre la diferencia de peso final e inicial y peso inicial de la membrana, mostró que estas pueden retener 690 veces su peso en agua, en tanto que en disoluciones del 95 % solo se retiene 10 veces su peso seco. Membranas prehinchadas en agua retienen cerca de 4 veces más con respecto a las no prehinchadas. El flujo de permeado es proporcional a la presión aplicada y la permeabilidad hidráulica para membranas de nueve días fue de 0,227 3 mL/kPa199 · cm2 · min, cerca del 50 % de la permeabilidad obtenida en membranas de 3 d . Con disoluciones de etanol las membranas presentaron permeabilidades menores en relación con las obtenidas con agua.

  4. 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.

  5. Gene inactivation in Lactococcus lactis: histidine biosynthesis.

    OpenAIRE

    Delorme, C; Godon, J J; Ehrlich, S D; Renault, P

    1993-01-01

    Lactococcus lactis strains from dairy and nondairy sources were tested for the ability to grow in the absence of histidine. Among 60 dairy strains tested, 56 required histidine, whereas only 1 of 11 nondairy strains had this requirement. Moreover, 10 of the 56 auxotrophic strains were able to grow in the presence of histidinol (Hol+), the immediate histidine precursor. This indicates that adaptation to milk often results in histidine auxotrophy. The histidine operon was detected by Southern h...

  6. 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.

  7. 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.

  8. Efeito de um elixir com óleos essenciais e de um colutório com delmopinol nas bactérias da placa bacteriana

    OpenAIRE

    Luís, Henrique Soares, 1966-

    2010-01-01

    Tese de doutoramento, Ciências e Tecnologias da Saúde (Higiene Oral), Universidade de Lisboa, Faculdade de Medicina Dentária, 2011 Este trabalho de investigação teve por objectivo avaliar e comparar a eficácia de um elixir com óleos essenciais e de um colutório com delmopinol nas bactérias da placa bacteriana. Para tal foram realizados dois ensaios laboratoriais, dois ensaios clínicos e um estudo descritivo. Dos ensaios laboratoriais concluiu-se que a concentração mínima ini...

  9. 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.

  10. 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

  11. Rewiring Lactococcus lactis for Ethanol Production

    DEFF Research Database (Denmark)

    Solem, Christian; Dehli, Tore Ibsen; Jensen, Peter Ruhdal

    2013-01-01

    to redirect the metabolism of LAB model organism Lactococcus lactis toward ethanol production. Codon-optimized Zymomonas mobilis pyruvate decarboxylase (PDC) was introduced and expressed from synthetic promoters in different strain backgrounds. In the wild-type L. lactis strain MG1363 growing on glucose, only...... small amounts of ethanol were obtained after introducing PDC, probably due to a low native alcohol dehydrogenase activity. When the same strains were grown on maltose, ethanol was the major product and lesser amounts of lactate, formate, and acetate were formed. Inactivating the lactate dehydrogenase...... genes ldhX, ldhB, and ldh and introducing codon-optimized Z. mobilis alcohol dehydrogenase (ADHB) in addition to PDC resulted in high-yield ethanol formation when strains were grown on glucose, with only minor amounts of by-products formed. Finally, a strain with ethanol as the sole observed...

  12. 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.

  13. 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

  14. 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.

  15. Lactococcus nasutitermitis sp. nov. isolated from a termite gut.

    Science.gov (United States)

    Yan Yang, Shu; Zheng, Ying; Huang, Zhou; Min Wang, Xue; Yang, Hong

    2016-01-01

    Bacterial strain M19T was isolated from the gut of a wood-feeding termite, Nasutitermes hainanensis. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M19T was related to members of the genus Lactococcus, with sequence similarities ranging from 84.8 to 95.5 %. Comparison of housekeeping gene ropB sequences revealed that strain M19T was well separated from Lactococcus fujiensis JCM 16395T and Lactococcus hircilactis 117T. The isolate was Gram-stain-positive, catalase-negative and non-motile. Cells were coccoid or ovoid-shaped, and occurred singly, in pairs or as short chains. Growth of strain M19T occurred at 10-40 °C and at pH 5.0-7.5. The DNA G+C content of strain M19T was 39.6 mol% and the major fatty acids were C16 : 0, cyclo-C19 : 0ω8c, C18 : 1ω9c, summed feature 7 and summed feature 8. Based on the phylogenetic, chemotaxonomic and phenotypic data presented, strain M19T represents a novel species of the genus Lactococcus, for which the name Lactococcus nasutitermitis sp. nov. is proposed. The type strain is M19T ( = CGMCC 1.15204T = NBRC 111537T). PMID:26546382

  16. 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...

  17. 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

  18. 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.

  19. 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

  20. 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

  1. pSEUDO, a Genetic Integration Standard for Lactococcus lactis

    NARCIS (Netherlands)

    Pinto, Joao P. C.; Zeyniyev, Araz; Karsens, Harma; Trip, Hein; Lolkema, Juke S.; Kuipers, Oscar P.; Kok, Jan

    2011-01-01

    Plasmid pSEUDO and derivatives were used to show that llmg_pseudo_10 in Lactococcus lactis MG1363 and its homologous locus in L. lactis IL1403 are suitable for chromosomal integrations. L. lactis MG1363 and IL1403 nisin-induced controlled expression (NICE) system derivatives (JP9000 and IL9000) and

  2. 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

  3. Autolysis of Lactococcus lactis is influenced by proteolysis

    NARCIS (Netherlands)

    Buist, G; Venema, G; Kok, J.

    1998-01-01

    The autolysin AcmA of Lactococcus lactis was shown to be degraded by the extracellular Lactococcal proteinase PrtP. Autolysis, as evidenced by reduction in optical density of a stationary-phase culture and concomitant release of intracellular proteins, was greatly reduced when L. lactis MG1363 cells

  4. Stability of Integrated Plasmids in the Chromosome of Lactococcus lactis

    NARCIS (Netherlands)

    Leenhouts, Kees J.; Kok, Jan; Venema, Gerhardus

    1990-01-01

    Derivatives of plasmids pBR322, pUB110, pSC101, and pTB19, all containing an identical fragment of lactococcal chromosomal DNA, were integrated via a Campbell-like mechanism into the same chromosomal site of Lactococcus lactis MG1363, and the transformants were analyzed for the stability of the inte

  5. 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...

  6. 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

  7. 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

  8. Production and secretion of heterologous proteins by Lactococcus lactis.

    NARCIS (Netherlands)

    Asseldonk, van M.

    1994-01-01

    Lactococcus lactis strains have been used for centuries in food fermentation, now appreciated as traditional biotechnology. They have been applied in the cheesemaking process and for the manufacturing of other dairy products. Years of experience with these lactic acid bacteria have led to a profound

  9. Meningencefalites bacterianas agudas em crianças: complicações e sequelas neurológicas

    Directory of Open Access Journals (Sweden)

    NATALINO WLADIMIR

    1999-01-01

    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.

  10. 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

    OpenAIRE

    Cláudia S.R. Deleito; Margarida Goréte F. do Carmo; Maria do Carmo A Fernandes; Antonio Carlos de S. Abboud

    2005-01-01

    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 ca...

  11. Evaluación de la actividad y la diversidad bacteriana con potencial bioremediador asociado a diferentes profundidades en el suelo del morro de Moravia mediante análisis de secuencias del Gen 16s rDNA

    OpenAIRE

    Gómez Zapata, Andrés

    2011-01-01

    En el presente trabajo, se evaluó y comparó la diversidad bacteriana más representativa a diferentes profundidades (0, 10, 20 y 30 metros) en un antiguo botadero de basuras. En el antiguo relleno sanitario de Moravia, se dispuso de desechos de todo tipo sin control alguno por 12 años, entre los años 1972 y 1984. El lugar presenta altos niveles de contaminantes a diferentes profundidades como cianuro y sulfuro de hidrogeno, metano, cromo, plomo y compuestos aromáticos como toluenos, benceno...

  12. 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

  13. 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.

  14. VALORACIÓN DE ENDOTOXINAS BACTERIANAS EN RANITIDINA Y PENICILINA G SÓDICA INYECTABLE MEDIANTE LA PRUEBA DE LISADO DEL AMEBOCITO DE Limulus

    Directory of Open Access Journals (Sweden)

    C. Carrillo

    2006-06-01

    Full Text Available Se realizó la estandarización y valoración de endotoxinas bacterianas por la técnica de Lisado del Amebocito de Limulus (LAL para dos productos farmacéuticos: penicilina G sódica y ranitidina inyectable por el método de gelificación. Para ello se tomaron tres muestras de tres lotes diferentes; las muestras fueron escogidas al azar y se tomó una muestra del principio, una de la mitad y otra del final de la producción para cada lote muestreado. Con las muestras de cada lote se realizó un pool, quedando así tres sublotes para analizar, dándole mayor confiabilidad al método. Se comprobó la sensibilidad del reactivo de LAL(0.25 UE/ml y se calificó al operario con el fin de obtener resultados confiables. Se consultó en la USP XXVI el límite de endotoxina para penicilina G sódica, 0.01 UE/100 UI y ranitidina 7 UE/mg. Se calculó la máxima dilución válida (MDV que fue de 1:400 y 1:700 respectivamente; se practicaron los ensayos preliminares (Unspike y Spike con los cuales se determinó la Dilución de trabajo para penicilina 1:100 y ranitidina 1:200. Con el ensayo final se valoró la presencia de endotoxinas bacterianas en los dos productos inyectables.

  15. 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.

  16. 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...

  17. 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

  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. 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.

  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. 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.

  2. 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. PMID:25295408

  3. Expression of the Staphylococcus hyicus Lipase in Lactococcus lactis

    OpenAIRE

    Drouault, Sophie; Corthier, Gerard; Ehrlich, S. Dusko; Renault, Pierre

    2000-01-01

    The extracellular Staphylococcus hyicus lipase was expressed under the control of different promoters in Lactococcus lactis and Bacillus subtilis. Its expression at high and moderate levels is toxic for the former and the latter hosts, respectively. In L. lactis, the lipase was expressed at a high level, up to 30% of the total cellular proteins, under the control of the inducible promoter PnisA. About 80% of the lipase remained associated with the cells. Close to half of this amount remained ...

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Genome Sequence of a Lactococcus lactis Strain Isolated from Salmonid Intestinal Microbiota.

    Science.gov (United States)

    Opazo, Rafael; Gajardo, Felipe; Ruiz, Mauricio; Romero, Jaime

    2016-01-01

    Lactococcus lactis is a common inhabitant of the intestinal microbiota of salmonids, especially those in aquaculture systems. Here, we present a genome sequence of a Lactococcus lactis strain isolated from the intestinal contents of rainbow trout reared in Chile. PMID:27563049

  7. Genome Sequence of Lactococcus garvieae 8831, Isolated from Rainbow Trout Lactococcosis Outbreaks in Spain▿

    OpenAIRE

    Aguado-Urda, Mónica; López-Campos, Guillermo H.; Gibello, Alicia; Cutuli, M. Teresa; López-Alonso, Victoria; Fernández-Garayzábal, José F.; Blanco, M. Mar

    2011-01-01

    Lactococcus garvieae is the etiological agent of lactococcosis, one of the most important disease threats to the sustainability of the rainbow trout farming industry. Here, we present the draft genome sequence of Lactococcus garvieae strain 8831, isolated from diseased rainbow trout, which is composed of 2,087,276 bp with a G+C content of 38%.

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

    Directory of Open Access Journals (Sweden)

    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

  9. Molecular characterization of bacterial populations of different soils Caracterização molecular de populações bacterianas de diferentes solos

    Directory of Open Access Journals (Sweden)

    Rodrigo Matheus Pereira

    2006-12-01

    por PCR, amplicons foram clonados e 139 clones de duas bibliotecas foram seqüenciados. O uso da técnica de 16S rRNA, gerou a identificação de diferentes populações de bactérias de solo pertencentes aos filos Acidobacteria Actinobacteria Bacteroidetes Firmicutes Proteobacteria Verrucomicrobia, Archaea, além das não classificadas. Diferenças entre as bibliotecas FS e CS foram observadas no tamanho dos filos. Um grande número de filos e, consequentemente, uma grande diversidade bacteriana foi observada no solo sob floresta. Estes dados foram confirmados pela análise de diversidade genética realizada. A caracterização de comunidades do solo apresentada neste trabalho contribuiu fornecendo dados para estudos posteriores sobre a dinâmica das populações bacterianas em solos de diferentes condições no Brasil.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. 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

    Directory of Open Access Journals (Sweden)

    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

  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. 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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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

    Directory of Open Access Journals (Sweden)

    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.

  19. Investigation of glycerol assimilation and cofactor metabolism in Lactococcus lactis

    DEFF Research Database (Denmark)

    Holm, Anders Koefoed

    was to investigate the suitability of lactic acid bacteria as production organisms for the production of biofuels and biochemicals. Specifically, the goal was to adapt the model organism Lactococcus lactis to convert crude glycerol, to value-added fuels or chemicals. Work was divided between four main areas: life...... glycerol assimilation operon was designed based on components from known glycerol metabolizers. Three genetic elements were placed in the operon: the glycerol facilitator glpF from E. coli, the glycerol dehydrogenase dhaD from Citrobacter freundii and the dihydroxyacetone kinase dhaK also from Citrobacter...

  20. Regulation of Proteolytic Enzyme Activity in Lactococcus lactis

    OpenAIRE

    Meijer, W.; Marugg, J D; Hugenholtz, J

    1996-01-01

    Two different Lactococcus lactis host strains, L. lactis subsp. lactis MG1363 and L. lactis subsp. cremoris SK1128, both containing plasmid pNZ521, which encodes the extracellular serine proteinase (PrtP) from strain SK110, were used to study the medium and growth-rate-dependent activity of three different enzymes involved in the proteolytic system of lactococci. The activity levels of PrtP and both the intracellular aminopeptidase PepN and the X-prolyl-dipeptidyl aminopeptidase PepXP were st...

  1. 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.

  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. 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

  4. Engineering of carbon distribution between glycolysis and sugar nucleobiosynthesis in Lactococcus lactis

    NARCIS (Netherlands)

    Boels, I.C.; Kleerebezem, M.; Vos, de W.M.

    2003-01-01

    We describe the effects of modulating the activities of glucokinase, phosphofructokinase, and phosphoglucomutase on the branching point between sugar degradation and the biosynthesis of sugar nucleotides involved in the production of exopolysaccharide biosynthesis by Lactococcus lactis. This was rea

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

    Directory of Open Access Journals (Sweden)

    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.

  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. 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...... engineering for the production of non-food related chemicals. Moreover, the status of being the first genetically modified organism to deliver immunoproteins alive to human has brought L. lactis considerable fame in biomedical research. Beside the exceptional industrial relevance of L. lactis, it is also...... 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...

  8. 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.

  9. Estomatitis ulcerativa infecciosa como consecuencia de un traumatismo en una Boa constrictor con desarrollo de neumonía bacteriana y septicemia.

    Directory of Open Access Journals (Sweden)

    Zulma Esperanza Rojas-Sereno

    2015-12-01

    Full Text Available Las neumonías bacterianas se asocian con estomatitis en serpientes, debido al descenso de los exudados de la cavidad hacia el pulmón. El objetivo de este reporte es describir los hallazgos clínicos, y el manejo diagnóstico y terapéutico de una Boa constrictor con estomatitis ulcerativa infecciosa (EUI postraumática que se complicó con neumonía bacteriana (NB y septicemia (SE. Un adulto de B. constrictor, ingresó con mucosas congestionadas, presencia de tierra en la cavidad oral, ulceraciones gingivales, deshidratación marcada y tegumento reseco con retención de muda. Presentó además letargia con postura anómala de la cabeza, con leve aumento de tamaño a nivel dorsal y antecedente de trauma. Se observó anemia no regenerativa y leve monocitosis relativa. Los hallazgos radiográficos fueron compatibles con fractura parietal e inflamación del tejido blando circundante. Se estabilizó el paciente y se realizó lavado bucal y debridación, posteriormente se administró tratamiento antibiótico y analgésico. La evolución no fue satisfactoria y terminó con la muerte del animal. El diagnóstico final fue una severa neumonía supurativa necrotizante de origen bacteriano posiblemente por Pasteurella o Pseudomona, con SE secundaria. El cuadro clínico fue típico de EUI de tipo crónico, con desarrollo de una NB y un cuadro septicémico, generando una tríada de patologías que hizo que el pronóstico del paciente fuera malo pese al continuo tratamiento. Es necesaria la determinación microbiológica del agente para mejorar la eficacia de la terapia antibiótica, aunque muchas de las bacterias de ofidios son resistentes a la antibioterapia.

  10. Infeções hospitalares bacterianas no século XXI

    OpenAIRE

    Simões, Cristina Maria Senra Barroso

    2016-01-01

    No decorrer do século XX, a descoberta da penicilina veio contribuir para o controlo das infeções bacterianas, entre elas as hospitalares. Contudo, em pleno século XXI, apesar do avanço tecnológico e científico, as infeções hospitalares estão associadas a altas taxas de morbilidade e mortalidade em todo o mundo. As infeções hospitalares apresentam-se como um problema transversal às várias instituições, e muito difícil de resolver. Nos últimos anos as infeções hospitalares têm registado um aum...

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

    OpenAIRE

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

    2008-01-01

    Cuerpos de inclusión, células bacterianas y composiciones que los contienen y sus usos. La presente invención se refiere a un cuerpo de inclusión aislado que comprende un polipéptido caracterizado porque el cuerpo da inclusión está en forma particulada. La presente invención también se refiere a una célula bacteriana que comprenda dicho cuerpo de inclusión. La presente invención se refiere además a una composición que comprende dicho cuerpo de inclusión y una célula eu...

  12. 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.

  13. Tratamento da vaginose bacteriana com gel vaginal de Aroeira (Schinus terebinthifolius Raddi: ensaio clínico randomizado

    Directory of Open Access Journals (Sweden)

    Amorim Melania Maria Ramos de

    2003-01-01

    Full Text Available OBJETIVOS: testar a eficácia e a tolerância do gel de aroeira (Schinus terebinthifolius Raddi para tratamento da vaginose bacteriana. MÉTODOS: quarenta e oito mulheres com vaginose bacteriana sintomática (de acordo com os critérios de Amsel foram incluídas em ensaio clínico randomizado, duplo-cego, controlado, comparando-se o uso do gel vaginal de aroeira (25 casos com placebo (23 casos. Os principais desfechos avaliados foram: taxa de cura, presença de lactobacilos na colpocitologia depois do tratamento e efeitos colaterais. Realizou-se análise estatística usando os testes chi2 e exato de Fisher, ao nível de significância de 5%. RESULTADOS: adotando-se os parâmetros clínicos de Amsel para vaginose bacteriana, a taxa de cura foi de 84% no grupo da aroeira e 47,8% no grupo placebo (p = 0,008. Observou-se freqüência significativamente maior de lactobacilos na colpocitologia entre as pacientes tratadas com aroeira (43,5% em relação ao placebo (4,3% (p = 0,002. Efeitos adversos relacionados ao tratamento não foram freqüentes em ambos os grupos. CONCLUSÕES: o presente estudo indica que o gel vaginal de aroeira é efetivo e seguro para o tratamento da vaginose bacteriana. Além disso, sugerem-se potenciais efeitos benéficos na flora vaginal.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. Genetic investigation within Lactococcus garvieae revealed two genomic lineages.

    Science.gov (United States)

    Ferrario, Chiara; Ricci, Giovanni; Borgo, Francesca; Rollando, Alessandro; Fortina, Maria Grazia

    2012-07-01

    The diversity of a collection of 49 Lactococcus garvieae strains, including isolates of dairy, fish, meat, vegetable and cereal origin, was explored using a molecular polyphasic approach comprising PCR-ribotyping, REP and RAPD-PCR analyses and a multilocus restriction typing (MLRT) carried out on six partial genes (atpA, tuf, dltA, als, gapC, and galP). This approach allowed high-resolution cluster analysis in which two major groups were distinguishable: one group included dairy isolates, the other group meat isolates. Unexpectedly, of the 12 strains coming from fish, four grouped with dairy isolates, whereas the others with meat isolates. Likewise, strains isolated from vegetables allocated between the two main groups. These findings revealed high variability within the species at both gene and genome levels. The observed genetic heterogeneity among L. garvieae strains was not entirely coherent with the ecological niche of origin of the strains, but rather supports the idea of an early separation of L. garvieae population into two independent genomic lineages. PMID:22568590

  19. Functional Expression of an Orchid Fragrance Gene in Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Adelene Ai Lian Song

    2012-02-01

    Full Text Available Vanda Mimi Palmer (VMP, an orchid hybrid of Vanda tesselata and Vanda Tan Chay Yan is a highly scented tropical orchid which blooms all year round. Previous studies revealed that VMP produces a variety of isoprenoid volatiles during daylight. Isoprenoids are well known to contribute significantly to the scent of most fragrant plants. They are a large group of secondary metabolites which may possess valuable characteristics such as flavor, fragrance and toxicity and are produced via two pathways, the mevalonate (MVA pathway or/and the 2-C-methyl-D-erythritol-4-phosphate (MEP pathway. In this study, a sesquiterpene synthase gene denoted VMPSTS, previously isolated from a floral cDNA library of VMP was cloned and expressed in Lactococcus lactis to characterize the functionality of the protein. L. lactis, a food grade bacterium which utilizes the mevalonate pathway for isoprenoid production was found to be a suitable host for the characterization of plant terpene synthases. Through recombinant expression of VMPSTS, it was revealed that VMPSTS produced multiple sesquiterpenes and germacrene D dominates its profile.

  20. 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.

  1. 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

    Surveillance of Antimicrobial Resistance (AGISAR) de la Organización Mundial de la Salud (OMS), en España y Dinamarca, en cuanto al uso ambulatoriode Critically Important Antimicrobials (CIA), así como analizarla relación entre éste y las resistencias bacterianas a ellos. Material y métodos: Los sistemas...... causantes de serias infecciones, resistentes a estos agentes, en ambos países. Resultados: En España, el uso de cefalosporinas y fluoroquinolonas, así como los porcentajes de bacterias resistentesa estos antibióticos son elevados, y superiores a los recogidosen Dinamarca. Aunque el consumo de macrólidos en...... ambospaíses es similar, la proporción de Streptococcus pneumoniae resistente a macrólidos es mayor en España. Conclusión: La elevada utilización de agentes CIA enatención primaria en España se aleja de las recomendaciones de la OMS de limitar su uso. Además tiene como consecuenciaunas elevadas tasas de...

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  4. 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

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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. Resistance to antibiotics in Lacid acid bacteria - strain Lactococcus

    Directory of Open Access Journals (Sweden)

    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

  8. 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.

  9. 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

  10. The structure of the lantibiotic lacticin 481 produced by Lactococcus lactis : location of the thioether bridges

    NARCIS (Netherlands)

    Hooven, Henno W. van den; Lagerwerf, Fija M.; Heerma, Wigger; Haverkamp, Johan; Piard, Jean-Christophe; Hilbers, Cornelis W.; Siezen, Roland J.; Kuipers, Oscar P.; Rollema, Harry S.

    1996-01-01

    The lantibiotic lacticin 481 is a bacteriocin produced by Lactococcus lactis ssp. lactis. This polypeptide contains 27 amino acids, including the unusual residues dehydrobutyrine and the thioether-bridging lanthionine and 3-methyllanthionine. Lacticin 481 belongs to a structurally distinct group of

  11. 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

  12. 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

  13. 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

  14. 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 f...

  15. Controlles modulation of folate polyglutamyl tail length by metabolic engineering of Lactococcus lactis

    NARCIS (Netherlands)

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

    2003-01-01

    The dairy starter bacterium Lactococcus lactis is able to synthesize folate and accumulates >90% of the produced folate intracellularly, predominantly in the polyglutamyl form. Approximately 10% of the produced folate is released into the environment. Overexpression of folC in L. lactis led to an

  16. 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

  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. Detection of bacteriophage-infected cells of Lactococcus lactis using flow cytometry

    DEFF Research Database (Denmark)

    Michelsen, Ole; Cuesta-Dominguez, Álvaro; Albrektsen, Bjarne;

    2007-01-01

    Bacteriophage infection in dairy fermentation constitutes a serious problem worldwide. We have studied bacteriophage infection in Lactococcus lactis by using the flow cytometer. The first effect of the infection of the bacterium is a change from cells in chains toward single cells. We interpret...

  19. 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

  20. Bacteriophage resistance of a Delta thyA mutant of Lactococcus lactis blocked in DNA replication

    DEFF Research Database (Denmark)

    Pedersen, M.B.; Jensen, Peter Ruhdal; Janzen, T.;

    2002-01-01

    The thyA gene, which encodes thymidylate synthase (TS), of Lactococcus lactis CHCC373 was sequenced, including the upstream and downstream regions. We then deleted part of thyA by gene replacement. The resulting strain, MBP71 DeltathyA, was devoid of TS activity, and in media without thymidine, s...

  1. 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

  2. Complete Genome Sequence of Lactococcus lactis subsp. lactis A12, a Strain Isolated from Wheat Sourdough

    Science.gov (United States)

    Guellerin, Maéva; Passerini, Delphine; Fontagné-Faucher, Catherine; Robert, Hervé; Gabriel, Valérie; Loux, Valentin; Klopp, Christophe; Le Loir, Yves; Coddeville, Michèle; Daveran-Mingot, Marie-Line; Ritzenthaler, Paul

    2016-01-01

    We report here the complete genome sequence of Lactococcus lactis subsp. lactis strain A12, a strain isolated from sourdough. The circular chromosome and the four plasmids reveal genes involved in carbohydrate metabolism that are potentially required for the persistence of this strain in such a complex ecosystem. PMID:27634985

  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. Sec-Mediated Transport of Posttranslationally Dehydrated Peptides in Lactococcus lactis

    NARCIS (Netherlands)

    Kuipers, Anneke; Wierenga, Jenny; Rink, Rick; Kluskens, Leon D.; Driessen, Arnold J.M.; Kuipers, Oscar P.; Moll, Gert N.

    2006-01-01

    Nisin is a lanthionine-containing antimicrobial peptide produced by Lactococcus lactis. Its (methyl)lanthionines are introduced by two posttranslational enzymatic steps involving the dehydratase NisB, which dehydrates serine and threonine residues, and the cyclase NisC, which couples these dehydrate

  5. 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

  6. Complete Genome Sequence of Lactococcus lactis subsp. lactis A12, a Strain Isolated from Wheat Sourdough.

    Science.gov (United States)

    Guellerin, Maéva; Passerini, Delphine; Fontagné-Faucher, Catherine; Robert, Hervé; Gabriel, Valérie; Loux, Valentin; Klopp, Christophe; Le Loir, Yves; Coddeville, Michèle; Daveran-Mingot, Marie-Line; Ritzenthaler, Paul; Le Bourgeois, Pascal

    2016-01-01

    We report here the complete genome sequence of Lactococcus lactis subsp. lactis strain A12, a strain isolated from sourdough. The circular chromosome and the four plasmids reveal genes involved in carbohydrate metabolism that are potentially required for the persistence of this strain in such a complex ecosystem. PMID:27634985

  7. Modeling peptide formation during the hydrolysis of beta-casein by Lactococcus lactis

    NARCIS (Netherlands)

    Munoz-Tamayo, R.; Groot, de J.; Wierenga, P.A.; Gruppen, H.; Zwietering, M.H.; Sijtsma, L.

    2012-01-01

    Hydrolysis of milk proteins by lactic acid bacteria leads to the formation of a large number of peptides. In this work, the hydrolysis of ß-casein by the protease PrtPI of Lactococcus lactis was studied. Experiments were carried out at different initial enzyme/substrate ratios. Identification and qu

  8. 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

  9. 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.

  10. 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

  11. Increasing acidification of nonreplicating Lactococcus lactis Delta thyA mutants by incorporating ATPase activity

    DEFF Research Database (Denmark)

    Pedersen, Martin Bastian; Købmann, Brian Jensen; Jensen, Peter Ruhdal;

    2002-01-01

    Lactococcus lactis MBP71 DeltathyA (thymidylate synthase) cannot synthesize dTTP de novo, and DNA replication is dependent on thymidine in the growth medium. In the nonreplicating state acidification by MBP71 was completely insensitive to bacteriophages (M. B. Pedersen, P. R. Jensen, T. Janzen, and...

  12. Lactococcus lactis YfiA is necessary and sufficient for ribosome dimerization

    NARCIS (Netherlands)

    Puri, Pranav; Eckhardt, Thomas H; Franken, Linda E; Fusetti, Fabrizia; Stuart, Marc C A; Boekema, Egbert J; Kuipers, Oscar P; Kok, Jan; Poolman, Berend

    2014-01-01

    Dimerization and inactivation of ribosomes in Escherichia coli is a two-step process that involves the binding of ribosome modulation factor (RMF) and hibernation promotion factor (HPF). Lactococcus lactisMG1363 expresses a protein, YfiA(Ll), which associates with ribosomes in the stationary phase o

  13. 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....

  14. 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

  15. 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

  16. Standardized Assay Medium To Measure Lactococcus lactis Enzyme Activities while Mimicking Intracellular Conditions

    NARCIS (Netherlands)

    Goel, A.; Santos, dos F.; Vos, de W.M.; Teusink, B.; Molenaar, D.

    2012-01-01

    Knowledge of how the activity of enzymes is affected under in vivo conditions is essential for analyzing their regulation and constructing models that yield an integrated understanding of cell behavior. Current kinetic parameters for Lactococcus lactis are scattered through different studies and per

  17. An ABC-type multidrug transporter of Lactococcus lactis possesses an exceptionally broad substrate specificity

    NARCIS (Netherlands)

    Poelarends, GJ; Mazurkiewicz, P; Putman, M; Cool, RH; van Veen, HW; Konings, WN

    2000-01-01

    LmrA is a 590-amino acid membrane protein which confers multidrug resistance on Lactococcus lactis cells by extruding amphiphilic compounds from the inner leaflet of the cytoplasmic membrane at the expense of ATP hydrolysis. Its structural and functional characteristics place it in the P-glycoprotei

  18. Supplementation with engineered Lactococcus lactis improves the folate status in deficient rats

    NARCIS (Netherlands)

    J.G. LeBlanc; W. Sybesma; M. Starrenburg; F. Sesma; W.M. de Vos; G. Savoy de Giori; J. Hugenholtz

    2010-01-01

    Objective: The aim of this study was to establish the bioavailability of different folates produced by engineered Lactococcus lactis strains using a rodent depletion-repletion bioassay. Methods: Rats were fed a folate-deficient diet, which produces a reversible subclinical folate deficiency, supplem

  19. 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

  20. 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.

  1. 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

  2. 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

  3. Mechanism of Citrate Metabolism by an Oxaloacetate Decarboxylase-Deficient Mutant of Lactococcus lactis IL1403

    NARCIS (Netherlands)

    Pudlik, Agata M.; Lolkema, Juke S.

    2011-01-01

    Citrate metabolism in resting cells of Lactococcus lactis IL1403(pFL3) results in the formation of two end products from the intermediate pyruvate, acetoin and acetate (A. M. Pudlik and J. S. Lolkema, J. Bacteriol. 193:706-714, 2011). Pyruvate is formed from citrate following uptake by the transport

  4. Sec-mediated secretion of bacteriocin enterocin P by Lactococcus lactis

    NARCIS (Netherlands)

    Herranz, C; Driessen, AJM

    2005-01-01

    Most lactic acid bacterium bacteriocins utilize specific leader peptides and dedicated machineries for secretion. In contrast, the enterococcal bacteriocin enterocin P (EntP) contains a typical signal peptide that directs its secretion when heterologously expressed in Lactococcus lactis. Signal pept

  5. Relationships between MDR proteins, bacteriocin production and proteolysis in Lactococcus lactis

    NARCIS (Netherlands)

    Gajic, Olivera

    2003-01-01

    The Gram-positive lactic acid bacterium Lactococcus lactis can harbour a wide variety of circular extrachromosomal DNA molecules, so-called plasmids. Many of the traits that make them useful for manufacturing of fermented food products (e.g. bacteriophage resistance, bacteriocin and proteinase produ

  6. 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

  7. Síntesis intratecal de C3c e inmunoglobulinas en niños con meningoencefalitis bacteriana

    OpenAIRE

    Bárbara Padilla-Docal; Alberto Juan Dorta-Contreras; Raisa Bu Coifiu-Fanego; Elena Noris-García; Hermes Fundora-Hernández; Jesus Callol-Barroso; Marlen González-Hernández

    2008-01-01

    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 ...

  8. 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.

  9. Estomatitis ulcerativa infecciosa como consecuencia de un traumatismo en una Boa constrictor con desarrollo de neumonía bacteriana y septicemia.

    OpenAIRE

    Zulma Esperanza Rojas-Sereno; Ximena Gómez-Acosta; Claudia Brieva-Rico

    2015-01-01

    Las neumonías bacterianas se asocian con estomatitis en serpientes, debido al descenso de los exudados de la cavidad hacia el pulmón. El objetivo de este reporte es describir los hallazgos clínicos, y el manejo diagnóstico y terapéutico de una Boa constrictor con estomatitis ulcerativa infecciosa (EUI) postraumática que se complicó con neumonía bacteriana (NB) y septicemia (SE). Un adulto de B. constrictor, ingresó con mucosas congestionadas, presencia de tierra en la cavidad oral, ulceracion...

  10. 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

  11. 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。

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. Factores para el escalado del proceso de producción de celulosa por fermentación estática

    OpenAIRE

    Luis Alfonso Caicedo; Da França, F. P.; Lopez, L.

    2011-01-01

    En la producción de celulosa bacteriana por el método estático, el factor de rendimiento Yp/s es afectado por la concentración de glucosa inicial y el tiempo de fermentación. Bajas concentraciones dan valores altos de Yp/s al inicio de la fermentación, mientras que altas concentraciones requieren tiempos largos para lograr valores comparables. El área superficial aumenta la producción de celulosa, pero existe una relación (área interfacial/volumen de medio) límite a partir de la cual la celul...

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Gene-cassette for adaptation of Lactococcus lactis to a plant environment

    OpenAIRE

    Doman-Pytka, Monika; Renault, Pierre; Bardowski, Jacek

    2004-01-01

    International audience The generally accepted opinion is that the natural niche for lactococci are plants. Several genes reminiscent of the environmental adaptation of these bacteria to the plant habitat were found as a result of our work on the pullulanase coding region in the Lactococcus lactis IBB500 strain. All genes were located within an 11-kb DNA fragment of a 35-kb plasmid. Analysis of the nucleotide sequence of the 11-kb DNA fragment showed three regions: (i) a middle region - enc...

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

    OpenAIRE

    A. Steen; Wiederhold, E.; T Gandhi; Breitling, R.; D. J. Slotboom

    2010-01-01

    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 lactis. The full-length protein was detected in the membrane of the bacterium, but the yields were too low (< 0.1% of membrane proteins) for in vitro functional and structural characterization, and indu...

  2. 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.

  3. 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...

  4. 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...

  5. Plasmid biology of natural Lactococcus lactis strains and molecular mechanisms of bacteriophage-host interaction

    OpenAIRE

    Fallico, Vincenzo

    2011-01-01

    Lacticin 3147, enterocin AS-48, lacticin 481, variacin, and sakacin P are bacteriocins offering promising perspectives in terms of preservation and shelf-life extension of food products and should find commercial application in the near future. The studies detailing their characterization and bio-preservative applications are reviewed. Transcriptomic analyses showed a cell wall-targeted response of Lactococcus lactis IL1403 during the early stages of infection with the lytic bacteriophage c2,...

  6. Some chemical and physical properties of nisin, a small-protein antibiotic produced by Lactococcus lactis.

    OpenAIRE

    Liu, W.; Hansen, J N

    1990-01-01

    Nisin is a small gene-encoded antimicrobial protein produced by Lactococcus lactis that contains unusual dehydroalanine and dehydrobutyrine residues. The reactivity of these residues toward nucleophiles was explored by reacting nisin with a variety of mercaptans. The kinetics of reaction with 2-mercaptoethane-sulfonate and thioglycolate indicated that the reaction pathway includes a binding step. Reaction of nisin at high pH resulted in the formation of multimeric products, apparently as a re...

  7. Engineering Trehalose Synthesis in Lactococcus lactis for Improved Stress Tolerance ▿ †

    OpenAIRE

    Carvalho, Ana Lúcia; Cardoso, Filipa S.; Bohn, Andreas; Neves, Ana Rute; Santos, Helena

    2011-01-01

    Trehalose accumulation is a common cell defense strategy against a variety of stressful conditions. In particular, our team detected high levels of trehalose in Propionibacterium freudenreichii in response to acid stress, a result that led to the idea that endowing Lactococcus lactis with the capacity to synthesize trehalose could improve the acid tolerance of this organism. To this end, we took advantage of the endogenous genes involved in the trehalose catabolic pathway of L. lactis, i.e., ...

  8. Prevention of gastrointestinal lead poisoning using recombinant Lactococcus lactis expressing human metallothionein-I fusion protein

    OpenAIRE

    Xue Xiao; Changbin Zhang; Dajun Liu; Weibin Bai; Qihao Zhang; Qi Xiang; Yadong Huang; Zhijian Su

    2016-01-01

    Low-level lead poisoning is an insidious disease that affects millions of children worldwide, leading to biochemical and neurological dysfunctions. Blocking lead uptake via the gastrointestinal tract is an important prevention strategy. With this in mind, we constructed the recombinant Lactococcus lactis strain pGSMT/MG1363, which constitutively expressed the fusion protein glutathione S-transferase (GST)–small molecule ubiquitin-like modifier protein (SUMO)–metallothionein-I (GST-SUMO-MT). T...

  9. 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...... ArgR and AhrC regulons by transcriptome analyses and show that both regulators are dedicated to the control of arginine metabolism in L. lactis....

  10. Novel Antibacterial Activity of Lactococcus Lactis Subspecies Lactis Z11 Isolated from Zabady

    OpenAIRE

    Enan, Gamal; Abdel-Shafi, Seham; Ouda, Sahar; Negm, Sally

    2013-01-01

    The purpose of this study was to select and characterize a probiotic bacterium with distinctive antimicrobial activities. In this respect, Lactococcus lactis subspecies lactis Z11 (L. lactis Z11) isolated from Zabady (Arabian yoghurt) inhibited other strains of lactic acid bacteria and some food-born pathogens including Listeria monocytogenes, Bacillus cereus and staphylococcus aureus. The inhibitory activity of cell free supernatant (CFS) of L. lactis Z11 isolated from zabady was lost by pro...

  11. Engineering of Carbon Distribution between Glycolysis and Sugar Nucleotide Biosynthesis in Lactococcus lactis

    OpenAIRE

    Boels, Ingeborg C.; Kleerebezem, Michiel; de Vos, Willem M.

    2003-01-01

    We describe the effects of modulating the activities of glucokinase, phosphofructokinase, and phosphoglucomutase on the branching point between sugar degradation and the biosynthesis of sugar nucleotides involved in the production of exopolysaccharide biosynthesis by Lactococcus lactis. This was realized by using a described isogenic L. lactis mutant with reduced enzyme activities or by controlled expression of the well-characterized genes for phosphoglucomutase or glucokinase from Escherichi...

  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. Tamanho do tubérculo-semente de batata não interfere na manifestação da murcha bacteriana Potato seed tuber size does not interfere with the incidence of potato bacterial wilt

    Directory of Open Access Journals (Sweden)

    Carlos A Lopes

    2011-06-01

    Full Text Available A batata-semente é comercializada no Brasil em diferentes tamanhos, conforme determinação do MAPA, variando do tipo 0 (zero, com tubérculos acima de 60 mm, até o tipo V, com tubérculos menores que 23 mm. Neste trabalho, foi avaliado o efeito do tamanho do tubérculo da batata-semente na manifestação da murcha bacteriana nas cultivares Agata, BRS Ana, Asterix e Bintje, em campo naturalmente infestado com Ralstonia solanacearum, em Brasília-DF. Foram usados tubérculos pequenos, médios e grandes, com aproximadamente 30, 50 e 90 mm em média, tamanhos correspondentes respectivamente aos tipos IV, II e 0 das normas do MAPA. Diferenças significativas quanto à incidência da doença foram encontradas entre cultivares: BRS Ana e Asterix não diferiram entre si e foram mais resistentes que Agata e Bintje que, por sua vez, tampouco diferiram entre si. As diferenças entre tamanhos de tubérculos e as interações entre cultivar e tamanho de tubérculos não foram significativas. Portanto concluiu-se que o tamanho de tubérculos dentro dos limites avaliados neste trabalho, não interferiu na manifestação da doença em testes de avaliação para resistência à murcha bacteriana.Potato seed tubers in Brazil are commercialized in different sizes as determined by the Ministry of Agriculture, Livestock and Food Supply. The sizes are classified in types, which vary from type 0 (zero, tubers above 60 mm, up to type V, tubers below 23 mm. In this work, we evaluated the influence of seed tuber size on the incidence of bacterial wilt on cultivars Agata, BRS Ana, Asterix, and Bintje, grown in a field naturally infested with Ralstonia solanacearum, in Brasilia, Brazil. We used small, medium and large tubers, measuring in average 30, 50 and 90 mm, which correspond respectively to types IV, II and 0 according to the Brazilian legislation. Significant differences in bacterial wilt incidences were detected among cultivars: BRS Ana and Asterix did not

  15. Evaluación del método cromogénico cinético para la determinación de endotoxinas bacterianas en el inyectable succinilcolina infantil 100 mg.

    Directory of Open Access Journals (Sweden)

    Nancy Burguet-Lago

    2015-01-01

    Full Text Available El objetivo del presente trabajo fue evaluar el método de lisado de amebocitos del Limulus (LAL en su variante cromogénica cinética para la determinación de endotoxinas bacterianas en el inyectable succinilcolina infantil 100 mg. Esta variante moni torea el desarrollo de color a través del tiempo y emplea una curva estándar representada por el tiempo de reacción en función de la concentración conocida de endotoxinas, en un rango de 0,005 a 50 UE/mL. La calificación del analista para obtener resultado s confiables fue confirmada durante la estandarización del método. Se realizó la caracterización del producto obteniéndose 1:8000 como factor de dilución al calcular la máxima dilución válida. La selección de la dilución de trabajo fue evaluada preliminarm ente en el ensayo de inhibición y realce definiéndose 1:4000 como dilución óptima. La dilución elegida se validó en tres lotes consecutivos del producto y se observó en todos los casos porcientos de recobrados enmarcados en los límites establecidos (50 - 200 % y el coeficiente de variación inferior al criterio de aceptación aprobado para este parámetro. Se aplicó el método a los tres lotes pilotos. A modo de conclusión podemos plantear que se demostró que la estandarización y validación del mismo permite su a plicación como ensayo de rutina para la determinación de endotoxinas bacterianas como parte del control de calidad y estudio de estabilidad de este producto.

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

    Directory of Open Access Journals (Sweden)

    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

  17. 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

  18. Desarrollo de plataformas bacterianas para la biosíntesis de polifenoles

    OpenAIRE

    Gutiérrez del Río Menéndez, Ignacio

    2015-01-01

    Los flavonoides son un grupo mayoritario de polifenoles integrado por 6000 compuestos diferentes ampliamente distribuidos en la dieta debido a su presencia ubicua en plantas. A pesar de que no son nutrientes esenciales para la vida, generan efectos beneficiosos para la salud realizando una importante función en la quimioprevención de enfermedades asociadas con el estrés oxidativo como son el cáncer o las enfermedades cardiovasculares y neurodegenerativas. El creciente interés por estos compue...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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

  2. 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

  3. 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.

  4. 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.

  5. Lactic acid production from a mixture of cultures of Lactococcus lactis and Streptococcus salivarius using batch fermentation

    Directory of Open Access Journals (Sweden)

    Liliana Serna Cock

    2006-12-01

    Full Text Available 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.

  6. 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

  7. Activities of amylase, proteinase, and lipase enzymes from Lactococcus chungangensis and its application in dairy products.

    Science.gov (United States)

    Konkit, Maytiya; Kim, Wonyong

    2016-07-01

    Several enzymes are involved in the process of converting milk to lactic acid and coagulated milk to curd and, therefore, are important in dairy fermented products. Amylase, proteinase, and lipase are enzymes that play an important role in degrading milk into monomeric molecules such as oligosaccharides, amino acids, and fatty acids, which are the main molecules responsible for flavors in cheese. In the current study, we determined the amylase, proteinase, and lipase activities of Lactococcus chungangensis CAU 28(T), a bacterial strain of nondairy origin, and compared them with those of the reference strain, Lactococcus lactis ssp. lactis KCTC 3769(T), which is commonly used in the dairy industry. Lactococcus chungangensis CAU 28(T) and L. lactis ssp. lactis KCTC 3769(T) were both found to have amylase, proteinase, and lipase activities in broth culture, cream cheese, and yogurt. Notably, the proteinase and lipase activities of L. chungangensis CAU 28(T) were higher than those of L. lactis ssp. lactis KCTC 3769(T), with proteinase activity of 10.50 U/mL in tryptic soy broth and 8.64 U/mL in cream cheese, and lipase activity of 100 U/mL of tryptic soy broth, and 100 U/mL of cream cheese. In contrast, the amylase activity was low, with 5.28 U/mL in tryptic soy broth and 8.86 U/mL in cream cheese. These enzyme activities in L. chungangensis CAU 28(T) suggest that this strain has potential to be used for manufacturing dairy fermented products, even though the strain is of nondairy origin. PMID:27108177

  8. 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

  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

    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......R homologue in Bacillus subtilis. Thus, our data point to a regulatory role of ClpE in turning off clpP gene expression following temporal heat shock induction, and we propose that this effect is mediated through CtsR....

  10. Exploring optimization parameters to increase ssDNA recombineering in Lactococcus lactis and Lactobacillus reuteri

    OpenAIRE

    van Pijkeren, Jan-Peter; Neoh, Kar Mun; Sirias, Denise; Findley, Anthony S.; Britton, Robert A.

    2012-01-01

    Single-stranded DNA (ssDNA) recombineering is a technology which is used to make subtle changes in the chromosome of several bacterial genera. Cells which express a single-stranded DNA binding protein (RecT or Bet) are transformed with an oligonucleotide which is incorporated via an annealing and replication-dependent mechanism. By in silico analysis we identified ssDNA binding protein homologs in the genus Lactobacillus and Lactococcus lactis. To assess whether we could further improve the r...

  11. Elucidating Flux Regulation of the Fermentation Modes of Lactococcus lactis:A Mutlilevel Study

    OpenAIRE

    Chan, Siu Hung Joshua; Solem, Christian; Jensen, Peter Ruhdal

    2014-01-01

    De mange års anvendelse af mælkesyrebakterien Lactococcus lactis (L. lactis) indenfor mejeriindustrien, har været medvirkende til at L. lactis er blevet en af de mest velkarakteriserede bakterier. Denne Gram positive bakterie, som har et lavt GC indhold, har en relativt simpel metabolisme og er let at modificere genetisk. Dette har gjort den til et attraktivt mål for ”metabolic engineering”, bl.a. med henblik på produktion af non-food relaterede kemikalier. Derudover har den status som den fø...

  12. 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

  13. 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.

  14. 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....

  15. 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...

  16. Secretion of biologically active murine interleukin-2 by Lactococcus lactis subsp. lactis.

    OpenAIRE

    Steidler, L; Wells, J M; Raeymaekers, A; Vandekerckhove, J; Fiers, W; Remaut, E

    1995-01-01

    Secretion of functional recombinant murine interleukin-2 (mIL2) by Lactococcus lactis was achieved by fusion of the sequence encoding mature mIL2 to the secretion signal leader of the lactococcal usp45 gene placed under transcriptional control of the phage T7 promoter-T7 RNA polymerase expression system. The recombinant mature mIL2 was one of only a few proteins which accumulated in the growth medium. Sequence analysis revealed correct processing at the first amino acid of the mature protein....

  17. 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...

  18. 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.

  19. 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

  20. 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

  1. 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

    OpenAIRE

    Enderson Petrônio de Brito Ferreira; André Nepomuceno Dusi; Gustavo Ribeiro Xavier; Norma Gouvêa Rumjanek

    2008-01-01

    The objective of this work was to determine the shifts on the PCR-DGGE profiles of bacterial communities associated to the rhizosphere of potato cultivars, in order to generate baseline information for further studies of environmental risk assessment of genetically modified potato plants. A greenhouse experiment was carried out with five potato cultivars (Achat, Bintje, Agata, Monalisa and Asterix), cultivated in pots containing soil from an integrated system for agroecological production. Th...

  2. 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...

  3. Produção e degradação in vitro de estruturas tubulares de celulose bacteriana

    Directory of Open Access Journals (Sweden)

    Vanessa A. Oliveira

    2013-01-01

    Full Text Available A necessidade de novos recursos em cardiologia tem direcionado a Engenharia de Tecidos ao desenvolvimento de vasos sanguíneos artificiais que atendam aos requisitos do organismo. Neste trabalho, estruturas tubulares de celulose bacteriana (CB foram produzidas e sua degradação in vitro foi avaliada. Através de microscopia eletrônica de varredura constatou-se que não houve alterações significativas na microestrutura e morfologia das fibras de CB após ensaios de degradação. Os ensaios de degradação em soluções fisiológicas PBS e salina revelaram uma degradação substancialmente baixa após 20 semanas. A baixa velocidade de degradação dos vasos é de grande importância, visto que o processo para a formação de novos vasos (angiogênese demanda tempo.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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

  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. 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

  12. Cold shock of Lactococcus lactis MG1363 are involved in cryoprotection and in the production of cold-induced proteins

    NARCIS (Netherlands)

    Wouters, J.A.; Frenkiel, H.; Vos, de W.M.; Kuipers, O.P.; Abee, T.

    2001-01-01

    Members of the group of 7-kDa cold-shock proteins (CSPs) are the proteins with the highest level of induction upon cold shock in the lactic acid bacterium Lactococcus lactis MG1363. By using double-crossover recombination, two L. lactis strains were generated in which genes encoding CSPs are disrupt

  13. Complete Genome of Lactococcus lactis subsp. cremoris UC509.9, Host for a Model Lactococcal P335 Bacteriophage

    NARCIS (Netherlands)

    Ainsworth, S.; Zomer, A.L.; Jager, V.C.L. de; Bottacini, F.; Hijum, S.A. van; Mahony, J.; Sinderen, D. van

    2013-01-01

    Here, we report the complete genome of Lactococcus lactis subsp. cremoris UC509.9, an Irish dairy starter. The circular chromosome of L. lactis UC509.9 represents the smallest among those of the sequenced lactococcal strains, while its large complement of eight plasmids appears to be a reflection of

  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...

  15. 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

  16. Complete Genome Sequence of Lactococcus lactis subsp. lactis CV56, a Probiotic Strain Isolated from the Vaginas of Healthy Women▿

    OpenAIRE

    Gao, Yong; Lu, Ying; Teng, Kun-Ling; Chen, Mei-Ling; Zheng, Hua-Jun; Zhu, Yong-Qiang; Zhong, Jin

    2011-01-01

    Lactic acid bacteria that exist in the urinogenital system play an important role in maintaining the health of the host. Here, we report the finished and annotated genome of a Lactococcus strain that was isolated from the vaginas of healthy women and shows probiotic properties, including nisin A production and adhesion to vaginal epithelial cells.

  17. Molecular Cloning and Sequence Analysis of the X-Prolyl Dipeptidyl Aminopeptidase Gene From Lactococcus lactis subsp. cremoris

    NARCIS (Netherlands)

    Mayo, Baltasar; Kok, Jan; Venema, Konraad; Bockelmann, Wilhelm; Teuber, Michael; Reinke, Heinz; Venema, Gerhardus

    1991-01-01

    Lactococcus lactis subsp. cremoris P8-2-47 contains an X-prolyl dipeptidyl aminopeptidase (X-PDAP; EC 3.4.14.5). A mixed-oligonucleotide probe prepared on the basis of the N-terminal amino acid sequence of the purified protein was made and used to screen a partial chromosomal DNA bank in Escherichia

  18. 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...

  19. 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

  20. 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 Lc...

  1. Complete Genome Sequence of Lactococcus lactis Strain AI06, an Endophyte of the Amazonian Açaí Palm

    OpenAIRE

    McCulloch, John Anthony; de Oliveira, Viviane Matoso; de Almeida Pina, André Vicioli; Pérez-Chaparro, Paula Juliana; Almeida, Lara Mendes; de Vasconcelos, Janaina Mota; de Oliveira, Layanna Freitas; da Silva, Daisy Elaine Andrade; Rogez, Hervé Louis Ghislain; CRETENET, Marina; Mamizuka, Elsa Masae; Nunes, Marcio Roberto Teixeira

    2014-01-01

    We report the genome, in a single chromosome, of Lactococcus lactis strain AI06, isolated from the mesocarp of the açaí fruit (Euterpe oleracea) in eastern Amazonia, Brazil. This strain is an endophyte of the açaí palm and also a component of the microbiota of the edible food product.

  2. 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

  3. Identification and functional characterization of the Lactococcus lactis rfb operon, required for dTDP-rhamnose biosynthesis

    NARCIS (Netherlands)

    Boels, I.C.; Beerthuyzen, M.M.; Kosters, M.H.; Kaauwen, van M.P.W.; Kleerebezem, M.; Vos, de W.M.

    2004-01-01

    dTDP-rhamnose is an important precursor of cell wall polysaccharides and rhamnose-containing exopolysaccharides (EPS) in Lactococcus lactis. We cloned the rfbACBD operon from L. lactis MG1363, which comprises four genes involved in dTDP-rhamnose biosynthesis. When expressed in Escherichia coli, the

  4. 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

  5. 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

  6. Complete Genome Sequence of Lactococcus lactis Strain AI06, an Endophyte of the Amazonian Açaí Palm.

    Science.gov (United States)

    McCulloch, John Anthony; de Oliveira, Viviane Matoso; de Almeida Pina, André Vicioli; Pérez-Chaparro, Paula Juliana; de Almeida, Lara Mendes; de Vasconcelos, Janaina Mota; de Oliveira, Layanna Freitas; da Silva, Daisy Elaine Andrade; Rogez, Hervé Louis Ghislain; Cretenet, Marina; Mamizuka, Elsa Masae; Nunes, Marcio Roberto Teixeira

    2014-01-01

    We report the genome, in a single chromosome, of Lactococcus lactis strain AI06, isolated from the mesocarp of the açaí fruit (Euterpe oleracea) in eastern Amazonia, Brazil. This strain is an endophyte of the açaí palm and also a component of the microbiota of the edible food product. PMID:25414513

  7. Raças de Xanthomonas spp. associadas à mancha-bacteriana em tomate para processamento industrial no Brasil Races of Xanthomonas spp. associated to bacterial spot in processing tomatoes in Brazil

    Directory of Open Access Journals (Sweden)

    Alice Maria Quezado-Duval

    2004-03-01

    Full Text Available A grande diversidade genética dos agentes causadores da mancha-bacteriana dificulta sobremaneira o desenvolvimento de variedades de pimentão e tomate com resistência durável. Setenta e dois isolados de Xanthomonas spp. provenientes de campos comerciais de tomate para processamento industrial dos estados de Goiás, Minas Gerais, Pernambuco e Bahia foram classificados em raças com base nas reações de genótipos diferenciais de tomateiro (Walter, Hawaii 7998 e NIL 216 e de Capsicum (ECW [Early Calwonder], ECW-10R, ECW-20R, ECW-30R e PI235047. As plantas foram inoculadas no estádio de três a cinco folhas verdadeiras por infiltração de suspensão bacteriana (5 ´ 10(8 UFC/ml na superfície abaxial da folha. Em seguida, foram mantidas em câmara de crescimento em fotoperíodo de 12 h/12 h (luz/escuro a 28ºC. A reação de hipersensibilidade foi observada até 36 horas após a inoculação, dependendo do genótipo da hospedeira. Foram identificadas as raças T1P2, T1P8 e T3 em X. axonopodis pv. vesicatoria; a raça T2 em X. vesicatoria; e as raças T2P7 e T2P8 em X. gardneri. A presença dos genes avrRxv e avrXv3 nos isolados que causaram reação de hipersensibilidade em 'Hawaii 7998' (raça T1 e 'NIL 216' (raça T3, respectivamente, foi confirmada por reação em cadeia da polimerase (PCR usando iniciadores específicos. Este é o primeiro relato da ocorrência no Brasil das raças T3, T1P8, T2P7 e T2P8.The great genetic diversity of the causal agents of bacterial spot is the main problem to the development of tomato and pepper varieties with durable resistance. Seventy two strains of Xanthomonas spp. collected from commercial fields of processing tomatoes in the states of Goiás, Minas Gerais, Pernambuco, and Bahia were classified in races according to their reactions on differential genotypes of tomato (Walter, Hawaii 7998 and NIL 216 and Capsicum [ECW (Early Calwonder, ECW-10R, ECW-20R, ECW-30R and PI 235047]. Bacterial suspensions (5

  8. Bacterial Levan: tecnological aspects, characteristics and production/ Levana Bacteriana: aspectos tecnológicos, características e produção

    Directory of Open Access Journals (Sweden)

    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

  9. Clinical outcome of neonatal bacterial meningitis according to birth weight Evolução clínica da meningite bacteriana neonatal de acordo com o peso de nascimento

    Directory of Open Access Journals (Sweden)

    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.

  10. Uso de Extractos de Pseudomonas sp (PB11 para el Control de la Mancha Bacteriana en tomate (Solanum lycopersicum Use of Pseudomonas sp (PB11 Extracts for Control of Bacterial Speck in Tomatoes (Solanum lycopersicum

    Directory of Open Access Journals (Sweden)

    Guadalupe Oyoque

    2011-01-01

    Full Text Available Se ha usado extracto libre de células de la cepa patógena Pseudomonas sp (PB11 causante de la mancha bacteriana en tomate para control de la misma cepa en plantas de tomate (Solanum lycopersicum en condiciones de invernadero. El extracto libre de células de PB11 fue aplicado a plantas de un mes de edad. Después de cuatro días, las plantas fueron inoculadas con una suspensión de Pseudomonas sp PB11. La severidad de la infección fue determinada por el número de lesiones necróticas presentes en cada planta y expresada como porcentaje de daño total. El extracto permitió la disminución de la infección en más del 60 % (pCell free extract from a pathogenic strain of Pseudomonas sp (PB11 able to cause bacterial speck was prompted for protection against that disease in tomato plants (Solana lycopersicum under greenhouse conditions. This extract was applied to one month old tomato plants. After four days, plants were inoculated with Pseudomonas sp PB11. Infection severity was determined by counting the number of necrotic lesions present in each plant and it were expressed as damage percentage. The extract led to a significantly infection reduction of more than 60% (p<0.05 . The protection effect was observed on the fifth day after inoculation and it was maintained for the next 30 days. This study shows the potential of PB11 cell free extract to induce a defence response in tomato plants to Pseudomonas sp (PB11 under greenhouse conditions.

  11. Adequação da contagem de células somáticas e da contagem bacteriana total em leite cru refrigerado aos parâmetros da legislação

    Directory of Open Access Journals (Sweden)

    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.

  12. Properties and genomic analysis of Lactococcus garvieae lysogenic bacteriophage PLgT-1, a new member of Siphoviridae, with homology to Lactococcus lactis phages.

    Science.gov (United States)

    Hoai, Truong Dinh; Nishiki, Issei; Yoshida, Terutoyo

    2016-08-15

    The lysogenic phage PLgT-1 is highly prevalent in Lactococcus garvieae, which is a serious bacterial pathogen in marine fish. Therefore, information regarding this phage is one of the key factors to predict the evolution of this bacterium. However, many properties of this phage, its complete genome sequence, and its relationship with other viral communities has not been investigated to date. Here, we demonstrated that the phage PLgT-1 was not only induced by an induction agent (Mitomycin C), but could be released frequently during cell division in a nutrient-rich environment or in natural seawater. Integration of PLgT-1 into non-lysogenic bacteria via transduction changed the genotype, resulting in the diversification of L. garvieae. The complete DNA sequence of PLgT-1 was also determined. This phage has a dsDNA genome of 40,273bp with 66 open reading frames (ORFs). Of these, the biological functions of 24 ORFs could be predicted but those of 42 ORFs are unknown. Thus, PLgT-1 is a novel phage with several novel proteins encoded in its genome. The strict MegaBLAST search program for the PLgT-1 genome revealed that this phage had no similarities with other previously investigated phages specific to L. garvieae (WP-2 and GE1). Notably, PLgT-1 was relatively homologous with several phages of Lactococcus lactis and 17 of the 24 predicted proteins encoded in PLgT-1 were homologous with the deduced proteins of various phages from these dairy bacteria. Comparative genome analysis revealed that the L. garvieae phage PLgT-1 was most closely related to the L. lactis phage TP712. However, they differed from each other in genome size and gene arrangement. The results obtained in this study suggest that the lysogenic phage PLgT-1 is a new member of the family Siphoviridae and has been involved in horizontal gene exchange with microbial communities, especially with L. lactis and its phages. PMID:27234995

  13. Alguns aspectos epidemiológicos da mancha bacteriana (Xanthomonas spp. do tomateiro na região de Caçador/SC Some epidemiological aspects of bacterial spot (Xanthomonas spp. of tomato in Caçador/SC, Brazil

    Directory of Open Access Journals (Sweden)

    Leandro Luiz Marcuzzo

    2009-06-01

    Full Text Available Objetivando explorar alguns aspectos da epidemiologia da de orvalho e um período médio de 13 horas continuas de umidade mancha bacteriana do tomateiro, incitada por Xanthomonas spp., relativa e"90%. A população bacteriana epifítica oscilou nas 10 em Caçador/SC, um ensaio a campo foi conduzido com plantas semanas após o plantio, conforme as condições climáticas, no inoculadas antes do transplantio. A cada sete dias e durante 19 entanto após o inicio dos sintomas manteve-se estável. O semanas foi monitorada a população bacteriana epifítica, as progresso da doença foi representado pelo modelo logístico y = condições climáticas e a severidade na planta. Constatou-se que o 0.99964/(1+exp(10.35989-0.69762*x e devido a pratica de inicio da epidemia teve concomitância com início da maturação apenas 1 colheita semanal, a severidade em frutos foi alta, fisiológica dos frutos do primeiro cacho, sendo que 77 dias antes atingindo 30,22% com produtividade total de117,88 ton.ha-1. Este do início da colheita não houve sintomas nas folhas. Observou-se, estudo epidemiológico servirá de um indicativo para determinação que mesmo em condição de estiagem, houve acréscimo da doença do inicio da epidemia e será usado na validação de um sistema de devido ao constante molhamento foliar decorrente da formação previsão para a mancha bacteriana do tomateiro.Aiming to explore some epidemiological aspects of bacterial spot of tomato incited by Xanthomonas spp., a field experiment was carried out in Caçador, SC. Tomato plants were inoculated with a bacterial suspension before transplanting. At seven-day intervals the bacterial population on leaf surface and disease severity were monitored during 19 weeks. Daily weather records were registered during the crop season. It was observed that epidemic onset coincided with physiological maturation of the first fruit clusters. Leaves were symptomless until 77 days before harvest. It was

  14. 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.

  15. BIODEGRADACIÓN BACTERIANA DE PLAGUICIDAS PERMETRINA Y CIPERMETRINA EN CULTIVO LOTE

    Directory of Open Access Journals (Sweden)

    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.

  16. 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

  17. 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

  18. Vaginose Bacteriana em Mulheres com Infertilidade e em Menopausadas Bacterial Vaginosis In Menopausal Women and in Women with Infertility

    Directory of Open Access Journals (Sweden)

    Miriam da Silva Wanderley

    2001-12-01

    Full Text Available Objetivo: analisar a prevalência de vaginose bacteriana (VB em mulheres inférteis e em menopausadas e os métodos mais comumente usados na prática clínica para o seu diagnóstico. Métodos: foram avaliadas retrospectivamente 104 pacientes na menopausa e 86 inférteis. A presença de corrimento vaginal característico, pH vaginal >4,5, teste das aminas (whiff test positivo e achado de vaginose bacteriana à coloração da secreção pelo Gram foram considerados positivos. Foi estabelecido diagnóstico de VB quando 3 dos 4 critérios acima fossem satisfeitos. Resultados: analisando os métodos diagnósticos separadamente observamos, entre as menopausadas, 29 pacientes com corrimento vaginal característico (28,1%, 10 (9,6% com whiff test positivo, 68 (65,4% com pH vaginal >4,5 e 34 (32,7% com teste do Gram positivo. Nas mulheres inférteis os resultados foram 20 (23,2%, 13 (15,1%, 61 (70,9% e 26 (30,2%, respectivamente. Ao analisarmos todos os critérios em conjunto, em 14 pacientes na menopausa (13,5% e em 15 inférteis (17,4% foi diagnosticada VB. Conclusão: a prevalência de VB foi similar nos 2 grupos de pacientes. Além disso, todos os métodos diagnósticos devem ser utilizados a fim de não se sub ou super-diagnosticar essa patologia.Purpose: to evaluate the prevalence of bacterial vaginosis (BV in menopausal and in infertile outpatients and to analyze the current clinical diagnostic methods. Methods: we evaluated retrospectively 104 menopausal women and 86 with infertility. Characteristic vaginal discharge on gynecological examination, pH >4.5, positive KOH whiff test, and bacterial vaginosis by Gram test were considered positive. BV was established when at least 3 out of 4 criteria were found. Results: among the menopausal women, 29 patients (28.1% were clinically positive for BV, 10 (9.6% had positive whiff test, 68 (65.4% vaginal pH >4.5, and 34 (32.7% positive Gram test. For the infertile patients the figures were 20 (23.2%, 13

  19. Oral administration of recombinant Neisseria meningitidis PorA genetically fused to H. pylori HpaA antigen increases antibody levels in mouse serum, suggesting that PorA behaves as a putative adjuvant

    Science.gov (United States)

    Vasquez, Abel E; Manzo, Ricardo A; Soto, Daniel A; Barrientos, Magaly J; Maldonado, Aurora E; Mosqueira, Macarena; Avila, Anastasia; Touma, Jorge; Bruce, Elsa; Harris, Paul R; Venegas, Alejandro

    2015-01-01

    The Neisseria meningitidis outer membrane protein PorA from a Chilean strain was purified as a recombinant protein. PorA mixed with AbISCO induced bactericidal antibodies against N. meningitidis in mice. When PorA was fused to the Helicobacter pylori HpaA antigen gene, the specific response against H. pylori protein increased. Splenocytes from PorA-immunized mice were stimulated with PorA, and an increase in the secretion of IL-4 was observed compared with that of IFN-γ. Moreover, in an immunoglobulin sub-typing analysis, a substantially higher IgG1 level was found compared with IgG2a levels, suggesting a Th2-type immune response. This study revealed a peculiar behavior of the purified recombinant PorA protein per se in the absence of AbISCO as an adjuvant. Therefore, the resistance of PorA to proteolytic enzymes, such as those in the gastrointestinal tract, was analyzed, because this is an important feature for an oral protein adjuvant. Finally, we found that PorA fused to the H. pylori HpaA antigen, when expressed in Lactococcus lactis and administered orally, could enhance the antibody response against the HpaA antigen approximately 3 fold. These observations strongly suggest that PorA behaves as an effective oral adjuvant. PMID:25750999

  20. Composição diferencial das comunidades bacterianas na rizosfera de variedas de cana-de-açúcar

    Directory of Open Access Journals (Sweden)

    Diogo Paes da Costa

    2014-12-01

    Full Text Available A cultura da cana-de-açúcar é de extrema importância no cenário agrícola nacional. No entanto, pouco se sabe sobre a estruturação das comunidades microbianas associadas aos solos e às rizosferas de tais plantas. O objetivo deste trabalho foi avaliar a estrutura e diversidade das comunidades de bactérias associadas ao solo e à rizosfera de seis variedades de cana-de-açúcar cultivadas no Estado de São Paulo (Brasil. As análises foram realizadas com base em métodos independentes de cultivo, em que a técnica de PCR-DGGE revelou alterações na rizosfera para os grupos de bactérias totais e também para os grupos de Alphaproteobacteria e Betaproteobacteria. Após essa análise, quatro amostras (três de rizosfera e uma de solo foram usadas para o sequenciamento da região V6 do gene 16S DNAr na plataforma Ion Torrent TM. Essa análise gerou um total de 95.812 sequências, dentro das quais houve a predominância das afiliadas aos filos Actinobacteria, Proteobacteria e Acidobateria . Os resultados revelaram que as comunidades bacterianas na rizosfera são distintas daquelas encontradas no solo. Foi possível ainda observar efeito diferencial de plantas das variedades. Alguns grupos bacterianos apresentaram menor frequência na rizosfera (Acidobacteria , enquanto outros se mostraram fortemente estimulados pela presença das raízes, comumente para todas as variedades (Betaproteobacteria , Nitrospora e Chloroflexi , ou em respostas variedade-específicas (Bacilli e Sphingobacteria .

  1. 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.

  2. Comparative effect of Pediococcus acidilactici and Lactococcus lactis on growth performance, survival and enzyme activity of western white leg shrimp (Litopenaeus vannamei)

    OpenAIRE

    Ahmadi, Sara

    2014-01-01

    This study was done in Shahid Kiani Marine Aquaculture Development Center, Choebde, Abadan in order to evaluate the effects of Pediiococcus acidilactici, Lactococcus lactis and vitamin C on growth performance, survival, enzymatic activities and immune responses of L. vannamei during three months. Treatments were included control group, Pediiococcus and Lactococcus treatments which fed with diet containing 1×10P9P cfu gP_1P bacteria and vitamin C. At the end of the experiment, the growth facto...

  3. 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

  4. Estudi de la població bacteriana endobronquial en la Malaltia Pulmonar Obstructiva Crònica. Aplicació del raspall protegit

    OpenAIRE

    Rosell i Gratacòs, Antoni

    2001-01-01

    Descripció del recurs: 6 març 2002 Títol obtingut de la portada digitalitzada La caracterització de la població bacteriana de les vies respiratòries baixes dels pacients amb Malaltia Pulmonar Obstructiva Crònica (MPOC) a partir de l'esput, tant en fase estable com en fase d'agudització, ha d'interpretar-se amb cautela per la inherent contaminació orofaringea de la mostra. Per aquest motiu, s'han intentat buscar mètodes alternatius com l'aspirat transtraqueal o les tècniques fibrobroncos...

  5. 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...

  6. 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 ...

  7. Análisis de costo/efectividad en Colombia de los tratamientos antimicrobianos para la vaginosis bacteriana en mujeres sintomáticas no gestantes

    OpenAIRE

    Díaz Ortega, Miguel Hernando

    2012-01-01

    Introducción: existen diferentes recomendaciones para el tratamiento de la vaginosis bacteriana, sin embargo, no existe evidencia en nuestro país de la razón de costo/efectividad de estas tecnologías. Objetivo:estimar desde la perspectiva del tercer pagador la razón de costo/efectividad promedio e incremental en Colombia de la monoterapia con metronidazol oral en multidosis, metronidazol intravaginal en gel, clindamicina oral en multidosis y clindamicina intravaginal en crema, comparados c...

  8. 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...

  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...... transcarbamoylase (pyrB) is the second enzyme in the pathway, whereas carbamoyl-phosphate synthetase subunit A (carA) is the small subunit of a heterodimeric enzyme, catalyzing the formation of carbamoyl phosphate. The carA gene product is shown to be required for both pyrimidine and arginine biosynthesis. The...

  10. Oxidative Stress at High Temperatures in Lactococcus lactis Due to an Insufficient Supply of Riboflavin

    DEFF Research Database (Denmark)

    Shen, Jing; Solem, Christian; Jensen, Peter Ruhdal;

    2013-01-01

    Lactococcus lactis MG1363 was found to be unable to grow at temperatures above 37°C in a defined medium without riboflavin, and the cause was identified to be dissolved oxygen introduced during preparation of the medium. At 30°C, growth was unaffected by dissolved oxygen and oxygen was consumed...... riboflavin to the medium, it was possible to improve growth and oxygen consumption at 37°C, and this also normalized the [ATP]-to-[ADP] ratio. A codon-optimized redox-sensitive green fluorescent protein (GFP) was introduced into L. lactis and revealed a more oxidized cytoplasm at 37°C than at 30°C. These...... results indicate that L. lactis suffers from heat-induced oxidative stress at increased temperatures. A decrease in intracellular flavin adenine dinucleotide (FAD), which is derived from riboflavin, was observed with increasing growth temperature, but the presence of riboflavin made the decrease smaller...

  11. Characterization of Lactococcus lactis mutants with improved performance at high temperatures and potential dairy applications

    DEFF Research Database (Denmark)

    Chen, Jun

    Lactococcus lactis (L. lactis) is a Gram-positive mesophile, which has considerable importance in the dairy industry for production of cheese and butter milk, and which carries the “GRAS” (generally recognized as safe) designation. Temperature has a great impact on dairy fermentation processes......, the latter because the increased energy consumption at high temperatures potentially could stimulate glycolysis. However in many cases the fitness is affected and mostly negative effects on productivity are observed. In this study, the non-GMO approach, experimental adaptation, was employed for isolating...... thermo-tolerant L. lactis. The adaptation was carried out using a serial-transfer regime at steadily increasing temperatures, and the strain used was L. lactis subsp. cremoris MG1363, which is a well-characterized dairy isolate. After exposure to increasing temperatures over 900 generations, one mutant...

  12. 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.

  13. 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.

  14. 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...... subtracting these contributions, approx. 0.3 mol of ATP/mol of glucose remained unaccounted for. A similar response to respiratory conditions (0.2 mol of ATP/mol of glucose) was observed in a mutant that had a decreased glucose uptake rate during growth on glucose caused by disruption of the PTSmannose...

  15. Angiotensin-converting enzyme inhibitory activity of milk fermented by wild and industrial Lactococcus lactis strains.

    Science.gov (United States)

    Rodríguez-Figueroa, J C; Reyes-Díaz, R; González-Córdova, A F; Troncoso-Rojas, R; Vargas-Arispuro, I; Vallejo-Cordoba, B

    2010-11-01

    Angiotensin I-converting enzyme inhibitory (ACEI) activity was evaluated and compared in milk fermented by wild and commercial starter culture Lactococcus lactis strains after 48 h of incubation. The highest ACEI activities were found in WSE from milk inoculated with wild L. lactis strains isolated from artisanal dairy products and commercial starter cultures. On the other hand, the lowest ACEI activities were found in WSE from milk inoculated with wild strains isolated from vegetables. Moreover, the IC(50) values (concentration that inhibits 50% activity) of WSE from artisanal dairy products were the lowest, indicating that these fractions were the most effective in inhibiting 50% of ACE activity. In fact, a strain isolated from artisanal cheese presented the lowest IC(50) (13 μg/mL). Thus, it appears that wild L. lactis strains isolated from artisanal dairy products and commercial starter cultures showed good potential for the production of fermented dairy products with ACEI properties. PMID:20965317

  16. 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.

  17. Effects of Lactococcus lactis on composition of intestinal microbiota: Role of nisin

    DEFF Research Database (Denmark)

    Bernbom, Nete; Licht, Tine Rask; Brogren, Carl-Henrik;

    2006-01-01

    This study examined the ability of (i) pure nisin, (ii) nisin-producing Lactococcus lactis strain CHCC5826, and (iii) the non-nisin-producing L. lactis strain CHCH2862 to affect the composition of the intestinal microbiota of human flora-associated rats. The presence of both the nisin......-producing and the non-nisin-producing L. lactis strains significantly increased the number of Bifidobacterium cells in fecal samples during the first 8 days but decreased the number of enterococci/streptococci in duodenum, ileum, cecum, and colon samples as detected by selective cultivation. No significant changes...... in the rat fecal microbiota were observed after dosage with nisin. Pearson cluster analysis of denaturing gradient gel electrophoresis profiles of the 16S rRNA genes present in the fecal microbial population revealed that the microbiota of animals dosed with either of the two L. lactis strains were different...

  18. 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

  19. 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

    Directory of Open Access Journals (Sweden)

    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

  20. 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.

  1. 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.

  2. 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 (p<0.05). The interaction of nisin 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. PMID:26310130

  3. 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

  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. 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.

  6. Heterologous production of methionine-γ-lyase from brevibacterium linens in lactococcus lactis and formation of volatile sulfur compounds

    OpenAIRE

    Hanniffy, Sean; Philo, Mark; Peláez, Carmen; Gasson, M. J.; Requena, Teresa; Martínez-Cuesta, M. Carmen

    2009-01-01

    The conversion of methionine to volatile sulfur compounds (VSCs) is of great importance in flavor formation during cheese ripening and is the focus of biotechnological approaches toward flavor improvement. A synthetic mgl gene encoding methionine-γ-lyase (MGL) from Brevibacterium linens BL2 was cloned into a Lactococcus lactis expression plasmid under the control of the nisin-inducible promoter PnisA. When expressed in L. lactis and purified as a recombinant protein, MGL was shown to degrade ...

  7. The carB Gene Encoding the Large Subunit of Carbamoylphosphate Synthetase from Lactococcus lactis Is Transcribed Monocistronically

    OpenAIRE

    Martinussen, Jan; Hammer, Karin

    1998-01-01

    The biosynthesis of carbamoylphosphate is catalyzed by the heterodimeric enzyme carbamoylphosphate synthetase. The genes encoding the two subunits of this enzyme in procaryotes are normally transcribed as an operon, but the gene encoding the large subunit (carB) in Lactococcus lactis is shown to be transcribed as an isolated unit. Carbamoylphosphate is a precursor in the biosynthesis of both pyrimidine nucleotides and arginine. By mutant analysis, L. lactis is shown to possess only one carB g...

  8. Secretion of TEM beta-lactamase with signal sequences isolated from the chromosome of Lactococcus lactis subsp. lactis.

    OpenAIRE

    Sibakov, M; Koivula, T; von Wright, A.; Palva, I

    1991-01-01

    With TEM beta-lactamase as a reporter gene, a set of expression-secretion-promoting fragments were isolated from the chromosome of Lactococcus lactis subsp. lactis. The fact that only translocated beta-lactamase renders cells resistant to ampicillin allowed direct ampicillin selection with an Escherichia coli vector (pKTH33). The clones showing the greatest ampicillin resistance were subcloned onto a replicon capable of replication in lactic acid bacteria (pVS2), and the nucleotide sequences ...

  9. Reassessing the Role of Staphylococcus aureus Clumping Factor and Fibronectin-Binding Protein by Expression in Lactococcus lactis

    OpenAIRE

    Que, Yok-Ai; François, Patrice; Haefliger, Jacques-Antoine; Entenza, José-Manuel; Vaudaux, Pierre; Moreillon, Philippe

    2001-01-01

    Since Staphylococcus aureus expresses multiple pathogenic factors, studying their individual roles in single-gene-knockout mutants is difficult. To circumvent this problem, S. aureus clumping factor A (clfA) and fibronectin-binding protein A (fnbA) genes were constitutively expressed in poorly pathogenic Lactococcus lactis using the recently described pOri23 vector. The recombinant organisms were tested in vitro for their adherence to immobilized fibrinogen and fibronectin and in vivo for the...

  10. Expression of a Heterologous Glutamate Dehydrogenase Gene in Lactococcus lactis Highly Improves the Conversion of Amino Acids to Aroma Compounds

    OpenAIRE

    Rijnen, Liesbeth; Courtin, Pascal; Gripon, Jean-Claude; Yvon, Mireille

    2000-01-01

    The first step of amino acid degradation in lactococci is a transamination, which requires an α-keto acid as the amino group acceptor. We have previously shown that the level of available α-keto acid in semihard cheese is the first limiting factor for conversion of amino acids to aroma compounds, since aroma formation is greatly enhanced by adding α-ketoglutarate to cheese curd. In this study we introduced a heterologous catabolic glutamate dehydrogenase (GDH) gene into Lactococcus lactis so ...

  11. Molecular and Functional Analyses of the metC Gene of Lactococcus lactis, Encoding Cystathionine β-Lyase

    OpenAIRE

    Fernández, María; Doesburg, Wim van; Rutten, Ger A.M.; Marugg, Joey D.; Alting, Arno C.; van Kranenburg, Richard; Oscar P. Kuipers

    2000-01-01

    The enzymatic degradation of amino acids in cheese is believed to generate aroma compounds and therefore to be essential for flavor development. Cystathionine β-lyase (CBL) can convert cystathionine to homocysteine but is also able to catalyze an α,γ elimination. With methionine as a substrate, it produces volatile sulfur compounds which are important for flavor formation in Gouda cheese. The metC gene, which encodes CBL, was cloned from the Lactococcus lactis model strain MG1363 and from str...

  12. Oral Treatment with Lactococcus lactis Expressing Staphylococcus hyicus Lipase Enhances Lipid Digestion in Pigs with Induced Pancreatic Insufficiency

    OpenAIRE

    Drouault, Sophie; Juste, Catherine; Marteau, Philippe; Renault, Pierre; Corthier, Gérard

    2002-01-01

    The Staphylococcus hyicus lip gene was cloned in Lactococcus lactis. Pancreatic insufficiency was induced by ligation of the pancreatic duct in pigs. In pigs who had undergone pancreatic ligation, the coefficient of fat absorption was higher after consumption of lipase-expressing L. lactis (91.9% ± 3.7%) than that after consumption of the inactive control strain (78.4% ± 2.4%).

  13. Intranasal Immunization with Recombinant Lactococcus lactis Secreting Murine Interleukin-12 Enhances Antigen-Specific Th1 Cytokine Production

    OpenAIRE

    Bermudez Humaran, Luis; Langella, Philippe; Cortes-Perez, Naima; Gruss, Alexandra; Tamez-Guerra, Reyes S; Oliveira, Sergio C.; Saucedo-Cardenas, Odila; Montes de Oca-Luna, Roberto; Le Loir, Yves

    2003-01-01

    Interleukin-12 (IL-12), a heterodimeric cytokine, plays an important role in cellular immunity to several bacterial, viral, and parasitic infections and has adjuvant activity when it is codelivered with DNA vaccines. IL-12 has also been used with success in cancer immunotherapy treatments. However, systemic IL-12 therapy has been limited by high levels of toxicity. We describe here inducible expression and secretion of IL-12 in the food-grade lactic acid bacterium Lactococcus lactis. IL-12 wa...

  14. Evaluación de la transferencia de oxígeno en cultivos con lactococcus lactis empleando un sistema de fermentación con aireación externa

    Directory of Open Access Journals (Sweden)

    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

  15. 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

  16. 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.

  17. Aspectos clínicos e laboratoriais da mastite induzida por inoculação intramamária de Staphylococcus aureus em vacas e búfalas

    OpenAIRE

    A.M. Lazzari; M.V.S. Oliveira; B. Moreti; Guimarães, G; Krug, F.; G. Noleto; A.J. Mesquita; J.P. Neves

    2014-01-01

    Vários aspectos relacionados à mastite bubalina precisam ser esclarecidos. Muitas condutas são adaptadas a essa espécie pelo conhecimento adquirido com a espécie bovina. Com este experimento, objetivou-se evidenciar particularidades da mastite em búfalas e vacas que tiveram uma glândula inoculada com 1,0 x 103 UFC de S. aureus. Os animais foram monitorados por cultura bacteriana do leite, California Mastitis Test (CMT), e escores para avaliação da severidade da mastite. Foram utilizados os se...

  18. Plasmid elimination of Lactococcus lactis%乳酸乳球菌的质粒消除

    Institute of Scientific and Technical Information of China (English)

    柳国霞; 范丽平; 霍贵成

    2009-01-01

    质粒消除是签定质粒和获得无质粒菌株的重要方法,是乳酸菌进行遗传学改造所需的一项重要技术.试验采用高温和消除剂结合的方法,对乳酸乳球菌镉抗性菌株进行质粒消除,探讨温度、消除剂吖啶橙的用量和作用时间对乳酸乳球菌镉抗性质粒消除的影响.结果表明,39℃高温可以质粒消除,而37和41℃均无此效果;独自吖叮橙作用未获得质粒消除菌株;39℃高温-吖啶橙同时作用比高温-吖啶橙交替作用消除率高,而39℃高温-20 μg·mL-1吖啶橙共同作用12 d,消除率可达98%.根据消除结果,以疑似功能性质粒为模板,进行PCR扩增,获得预期片段,进一步证实了其功能.%Plasmid elimination is a key method of plasmid identificaton and obtaining non-plasmid strain, and it is an important technology which was needed by genetics transformation in lactic acid bacteria. High temperature and the elimination agent were combined by plasmid elimination for a cadmium-resistant Lactococcus lactis strains, the amount and the time by using temperature and eUminaton agent acridine orange (AO) were approached on the effect of cadmium-resistant Lactococcus lactis plasmid. The results showed that 39℃ high temperature could eliminate the plasmid, but 37 and 41℃ had no effects. Plasmid elimination strain was not obtained by using AO alone, the elimination rate by the method of both high temperature and AO at the same time was higher than that of by interchanging between high temperature and AO. The combined effect of 39℃ temperature and 20 μg·mL-1 AO for 12 days was significant, the elimination rate was as high as 98%. According to the results, PCR amplification was based on the suspected functional plasmid as a template, achieved the desired fragment, and further confirmed its functions.

  19. Detection and characterization of bacteriocin-producing Lactococcus lactis strains Detecção e caracterização de Lactococcus lactis produtores de bacteriocinas

    Directory of Open Access Journals (Sweden)

    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. Celulitis por citomegalovirus

    Directory of Open Access Journals (Sweden)

    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.

  1. Meningitis por Kluyvera sp. en una paciente con una derivación lumbo-peritoneal: reporte de un caso

    Directory of Open Access Journals (Sweden)

    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.

  2. Bacterial survival rate on toothbrushes and their decontamination with antimicrobial solutions Taxa de sobrevivência bacteriana em escovas dentais e sua descontaminação com soluções antimicrobianas

    Directory of Open Access Journals (Sweden)

    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

  3. 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

    Directory of Open Access Journals (Sweden)

    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

  4. 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

    Directory of Open Access Journals (Sweden)

    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.

  5. 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

  6. 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. PMID:26697381

  7. Exploring optimization parameters to increase ssDNA recombineering in Lactococcus lactis and Lactobacillus reuteri.

    Science.gov (United States)

    Van Pijkeren, Jan-Peter; Neoh, Kar Mun; Sirias, Denise; Findley, Anthony S; Britton, Robert A

    2012-01-01

    Single-stranded DNA (ssDNA) recombineering is a technology which is used to make subtle changes in the chromosome of several bacterial genera. Cells which express a single-stranded DNA binding protein (RecT or Bet) are transformed with an oligonucleotide which is incorporated via an annealing and replication-dependent mechanism. By in silico analysis we identified ssDNA binding protein homologs in the genus Lactobacillus and Lactococcus lactis. To assess whether we could further improve the recombineering efficiency in Lactobacillus reuteri ATCC PTA 6475 we expressed several RecT homologs in this strain. RecT derived from Enterococcus faecalis CRMEN 19 yielded comparable efficiencies compared with a native RecT protein, but none of the other proteins further increased the recombineering efficiency. We successfully improved recombineering efficiency 10-fold in L. lactis by increasing oligonucleotide concentration combined with the use of oligonucleotides containing phosphorothioate-linkages (PTOs). Surprisingly, neither increased oligonucleotide concentration nor PTO linkages enhanced recombineering in L. reuteri 6475. To emphasize the utility of this technology in improving probiotic features we modified six bases in a transcriptional regulatory element region of the pdu-operon of L. reuteri 6475, yielding a 3-fold increase in the production of the antimicrobial compound reuterin. Directed genetic modification of lactic acid bacteria through ssDNA recombineering will simplify strain improvement in a way that, when mutating a single base, is genetically indistinguishable from strains obtained through directed evolution. PMID:22750793

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Novel antibacterial activity of lactococcus lactis subspecies lactis z11 isolated from zabady.

    Science.gov (United States)

    Enan, Gamal; Abdel-Shafi, Seham; Ouda, Sahar; Negm, Sally

    2013-09-01

    The purpose of this study was to select and characterize a probiotic bacterium with distinctive antimicrobial activities. In this respect, Lactococcus lactis subspecies lactis Z11 (L. lactis Z11) isolated from Zabady (Arabian yoghurt) inhibited other strains of lactic acid bacteria and some food-born pathogens including Listeria monocytogenes, Bacillus cereus and staphylococcus aureus. The inhibitory activity of cell free supernatant (CFS) of L. lactis Z11 isolated from zabady was lost by proteolytic enzymes, heat resistant. Consequently, the active substance(s) of CFS was characterized as a bacteriocin. This bacteriocin has been shown to consist of protein but has no lipidic or glucidic moieties in its active molecule. Its activity was stable in the pH range 2.0 to 7.0 and was not affected by organic solvents. The L. lactis Z11 bacteriocin was produced in CFS throughout the mide to the late exponential phase of growth of the producer organism and maximum bacteriocin production was obtained at initial pH 6.5 at incubation temperature of about 30°C. PMID:24151453

  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....... lactis PGM was dependent on 2,3-bisphosphoglyceric acid for activity, which showed that the enzyme is of the dPGM type in accordance with its predicted homology to dPGM enzymes from other organisms. In conclusion, PGM from L. lactis is a highly efficient catalyst, which partially explains why this enzyme...... at highly reduced PGM activities. At the wild-type level PGM operated very far from V-max. Consequently, in a strain with only 15% PGM activity, the catalytic rate of PGM was almost six times higher than in the wildtype. K-m of PGM for 3-phosphoglycerate was 1.0 m M and k(cat) was 3,200 s(-1). The L...

  14. 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.

  15. 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

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

    Science.gov (United States)

    Chen, Jun; Shen, Jing; Ingvar Hellgren, Lars; Ruhdal Jensen, Peter; Solem, Christian

    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 temperature. At the maximal permissive temperature for the wild-type, 38 °C, TM29 grows 33% faster and has a 12% higher specific lactate production rate than its parent MG1363, which results in fast lactate accumulation. Genome sequencing was used to reveal the mutations accumulated, most of which were shown to affect thermal tolerance. Of the mutations with more pronounced effects, two affected expression of single proteins (chaperone; riboflavin transporter), two had pleiotropic effects (RNA polymerase) which changed the gene expression profile, and one resulted in a change in the coding sequence of CDP-diglyceride synthase. A large deletion containing 10 genes was also found to affect thermal tolerance significantly. With this study we demonstrate a simple approach to obtain non-GMO derivatives of the important L. lactis that possess properties desirable by the industry, e.g. thermal robustness and increased rate of acidification. The mutations we have identified provide a genetic basis for further investigation of thermal tolerance. PMID:26388459

  17. Improvement of bovine ß-lactoglobulin production and secretion by Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    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.

  18. Heterologous protein secretion in Lactococcus lactis: a novel antigen delivery system

    Directory of Open Access Journals (Sweden)

    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.

  19. A genome-scale integration and analysis of Lactococcus lactis translation data.

    Directory of Open Access Journals (Sweden)

    Julien Racle

    Full Text Available Protein synthesis is a template polymerization process composed by three main steps: initiation, elongation, and termination. During translation, ribosomes are engaged into polysomes whose size is used for the quantitative characterization of translatome. However, simultaneous transcription and translation in the bacterial cytosol complicates the analysis of translatome data. We established a procedure for robust estimation of the ribosomal density in hundreds of genes from Lactococcus lactis polysome size measurements. We used a mechanistic model of translation to integrate the information about the ribosomal density and for the first time we estimated the protein synthesis rate for each gene and identified the rate limiting steps. Contrary to conventional considerations, we find significant number of genes to be elongation limited. This number increases during stress conditions compared to optimal growth and proteins synthesized at maximum rate are predominantly elongation limited. Consistent with bacterial physiology, we found proteins with similar rate and control characteristics belonging to the same functional categories. Under stress conditions, we found that synthesis rate of regulatory proteins is becoming comparable to proteins favored under optimal growth. These findings suggest that the coupling of metabolic states and protein synthesis is more important than previously thought.

  20. 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...... for dnaK, dnaJ and groELS after transfer from 30°C to 43°C when MG1363 was grown in defined medium. The dnaK gene showed a 100-fold induction level 15 min after temperature shifting. Induction of the first two genes in the dnaK operon, orf1 and grpW, resembled the pattern observed for the above genes......, 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...

  1. 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.

  2. 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.

  3. 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

    of the rapid formation of a complex that isomerized to the final charge-transfer complex. Orotate and 3,5-diOHB bind too quickly to follow directly, but their dissociation kinetics were studied by competition and described adequately with a single step. Crystal structures of both inhibitor complexes were......-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...

  4. Prevention of gastrointestinal lead poisoning using recombinant Lactococcus lactis expressing human metallothionein-I fusion protein.

    Science.gov (United States)

    Xiao, Xue; Zhang, Changbin; Liu, Dajun; Bai, Weibin; Zhang, Qihao; Xiang, Qi; Huang, Yadong; Su, Zhijian

    2016-01-01

    Low-level lead poisoning is an insidious disease that affects millions of children worldwide, leading to biochemical and neurological dysfunctions. Blocking lead uptake via the gastrointestinal tract is an important prevention strategy. With this in mind, we constructed the recombinant Lactococcus lactis strain pGSMT/MG1363, which constitutively expressed the fusion protein glutathione S-transferase (GST)-small molecule ubiquitin-like modifier protein (SUMO)-metallothionein-I (GST-SUMO-MT). The thermodynamic data indicated that the average number of lead bound to a GST-SUMO-MT molecule was 3.655 and this binding reaction was a spontaneous, exothermic and entropy-increasing process. The total lead-binding capacity of pGSMT/MG1363 was 4.11 ± 0.15 mg/g dry mass. Oral administration of pGSMT/MG1363 (1 × 10(10) Colony-Forming Units) to pubertal male rats that were also treated with 5 mg/kg of lead acetate daily significantly inhibited the increase of blood lead levels, the impairment of hepatic function and the decrease of testosterone concentration in the serum, which were all impaired in rats treated by lead acetate alone. Moreover, the administration of pGSMT/MG1363 for 6 weeks did not affect the serum concentration of calcium, magnesium, potassium or sodium ions. This study provides a convenient and economical biomaterial for preventing lead poisoning via the digestive tract. PMID:27045906

  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. Induction and characterization of a lysogenic bacteriophage of Lactococcus garvieae isolated from marine fish species.

    Science.gov (United States)

    Hoai, T D; Yoshida, T

    2016-07-01

    This study investigated the presence of prophages in Lactococcus garvieae isolated from several marine fish species in Japan. Representative strains of 16 bacterial genotypes (S1-S16) selected from more than 400 L. garvieae isolates were used to induce lysogenic bacteriophages. These strains were treated with 500 ng mL(-1) freshly prepared mitomycin C. A cross-spotting assay was performed to validate the lysogenic and indicator strains. The lysogenic strains were selected for isolation and concentration of the phages. Phage DNA was digested with EcoRI for biased sinusoidal field gel electrophoresis analysis. Polymerase chain reaction (PCR) was used to detect integrated prophage DNA. Of the 16 representative bacterial genotypes, 12 strains integrated prophages as indicated by the PCR assay, and 10 phages were detected and isolated using two indicator bacterial strains. Analysis of genomic DNA showed that these phages were homologous and named as PLgT-1. Transmission electron microscopy revealed that the morphology of PLgT-1 was consistent with the virus family Siphoviridae. PCR analysis of the prophage DNA revealed that all of the S1 genotype strains were lysogenic (30/30), but none of the S16 genotype strains were lysogenic (0/30). This is the first study to investigate lysogenic bacteriophages from L. garvieae. PMID:26471724

  7. Endoftalmites bacterianas com culturas positivas: uma revisão de 6 anos Culture proven bacterial endophthalmitis: a 6-year review

    Directory of Open Access Journals (Sweden)

    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

  8. DESENVOLVIMENTO DE MODELO DE PERITONITE BACTERIANA PARA AVALIAÇÃO DO TRATAMENTO MEDIANTE ACESSO LAPAROTÔMICO E VIDEO-LAPAROSCÓPICO

    OpenAIRE

    Salgado Jr W.; Cunha FQ; Sankarankuty A.S.; JS Santos

    2001-01-01

    Introdução: O emprego do acesso videolaparoscópico no tratamento das afecções digestivas que cursam com peritonite generalizada é motivo de controvérsia. Objetivo: Desenvolver um modelo de peritonite bacteriana para avaliação do tratamento mediante acesso laparotômico e videolaparoscópico. Métodos: Ratos machos Wistar foram submetidos à ligadura de ceco (CLP) sob molde rígido de 3mm de diâmetro; na seqüência foram feitas 14 punções no ceco com agulha 15X10. Após 6 horas de indução da peritoni...

  9. Dinâmica das populações bacterianas em solos de Cerrados Dynamic of bacterial populations from Cerrado soils

    Directory of Open Access Journals (Sweden)

    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

  10. 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.

  11. 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.

  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 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

  13. Biofertilizante agrobio: Uma alternativa no controle da mancha bacteriana em mudas de pimentão (Capsicum annuum l.)

    OpenAIRE

    Deleito, Cláudia Sayão Ramirez; Carmo, Margarida Goréte Ferreira do; Fernandes, Maria do Carmo de Araújo; Abboud, Antônio Carlos de Souza

    2004-01-01

    Agrobio é um biofertilizante líquido fabricado à base de esterco bovino, água, melaço e sais minerais, que são submetidos a um processo de fermentação à temperatura ambiente por 56 dias em recipientes abertos. Este produto tem sido largamente utilizado com sucesso por agricultores orgânicos e convencionais em todo o estado do Rio de Janeiro, no controle de várias enfermidades vegetais em diferentes culturas. Em bioensaios realizados em casa de vegetação, observou-se uma ação bacteriostática e...

  14. 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

  15. 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。

  16. Identification of the Minimal Replicon of Lactococcus lactis subsp. lactis UC317 Plasmid pCI305

    OpenAIRE

    Hayes, Finbarr; Daly, Charles; Fitzgerald, Gerald F.

    1990-01-01

    Replication functions of the stable, cryptic 8.7-kilobase (kb) plasmid pCI305 from multi-plasmid-containing Lactococcus lactis subsp. lactis UC317 were studied. Analysis of this replicon was facilitated by the construction of replication probe vectors that consisted of the pBR322 replication region, a pUC18-derived multiple cloning site, and either the cat gene of pC194 (pCI341; 3.1 kb) or the erm gene of pAMβ1 (pCI3330; 4.0 kb). Plasmid pCI305 was introduced into plasmid-free L. lactis subsp...

  17. 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

  18. 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......-heart infusion broth (BHI) at 30-degrees C, the pathogen declined from 5x10(5) to fewer than 5 cfu ml(-1) within 31 h. The effect was not due to lactic acid inhibition. Growth and nisin production by L- lactis ATCC 11454 were investigated under the conditions of temperature and salt used for light preservation...

  19. 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.

  20. 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.

  1. Integrating biocompatible chemistry and manipulating cofactor partitioning in metabolically engineeredLactococcus lactisfor fermentative production of (3S)-acetoin

    DEFF Research Database (Denmark)

    Liu, Jianming; Solem, Christian; Jensen, Peter Ruhdal

    2016-01-01

    Biocompatible chemistry (BC), i.e. non-enzymatic chemical reactions compatible with living organisms, is increasingly used in conjunction with metabolically engineered microorganisms for producing compounds that do not usually occur naturally. Here we report production of one such compound, (3S......)-acetoin, a valuable precursor for chiral synthesis, using a metabolically engineered Lactococcus lactis strain growing under respiratory conditions with ferric iron serving as a BC component. The strain used has all competing product pathways inactivated, and an appropriate cofactor balance is achieved by fine...

  2. 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...

  3. Expression of PprI from Deinococcus radiodurans Improves Lactic Acid Production and Stress Tolerance in Lactococcus lactis

    OpenAIRE

    Dong, Xiangrong; Tian, Bing; Dai, Shang; Li, Tao; Guo, Linna; Tan, Zhongfang; JIAO, Zhen; Jin, Qingsheng; Wang, Yanping; Hua, Yuejin

    2015-01-01

    PprI is a general switch protein that regulates the expression of certain proteins involved in pathways of cellular resistance in the extremophilic bacterium Deinococcus radiodurans. In this study, we transformed pprI into Lactococcus lactis strain MG1363 using the lactococcal shuttle vector pMG36e and investigated its effects on the tolerance and lactic acid production of L. lactis while under stress. PprI was stably expressed in L. lactis as confirmed by western blot assays. L. lactis expre...

  4. In Situ Determination of the Intracellular pH of Lactococcus lactis and Lactobacillus plantarum during Pressure Treatment

    OpenAIRE

    Molina-Gutierrez, Adriana; Stippl, Volker; Delgado, Antonio; Gänzle, Michael G.; Rudi F. Vogel

    2002-01-01

    Hydrostatic pressure may affect the intracellular pH of microorganisms by (i) enhancing the dissociation of weak organic acids and (ii) increasing the permeability of the cytoplasmic membrane and inactivation of enzymes required for pH homeostasis. The internal pHs of Lactococcus lactis and Lactobacillus plantarum during and after pressure treatment at 200 and 300 MPa and at pH values ranging from 4.0 to 6.5 were determined. Pressure treatment at 200 MPa for up to 20 min did not reduce the vi...

  5. Mdt(A), a New Efflux Protein Conferring Multiple Antibiotic Resistance in Lactococcus lactis and Escherichia coli

    OpenAIRE

    Perreten, Vincent; Schwarz, Franziska V.; Teuber, Michael; Levy, Stuart B.

    2001-01-01

    The mdt(A) gene, previously designated mef214, from Lactococcus lactis subsp. lactis plasmid pK214 encodes a protein [Mdt(A) (multiple drug transporter)] with 12 putative transmembrane segments (TMS) that contain typical motifs conserved among the efflux proteins of the major facilitator superfamily. However, it also has two C-motifs (conserved in the fifth TMS of the antiporters) and a putative ATP-binding site. Expression of the cloned mdt(A) gene decreased susceptibility to macrolides, lin...

  6. 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; Magni, Christian

    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

  7. Characterization and overexpression of the Lactococcus lactis pepN gene and localization of its product, aminopeptidase N.

    OpenAIRE

    van Alen-Boerrigter, I J; Baankreis, R; de Vos, W M

    1991-01-01

    The chromosomal pepN gene encoding lysyl-aminopeptidase activity in Lactococcus lactis has been identified in a lambda EMBL3 library in Escherichia coli by using an immunological screening with antiserum against a purified aminopeptidase fraction. The pepN gene was localized and subcloned in E. coli on the basis of its expression and hybridization to a mixed-oligonucleotide probe for the previously determine N-terminal amino acid sequence of lysyl-aminopeptidase (P. S. T. Tan and W. N. Koning...

  8. Lactococcus bacteriophages isolated from whey and their effects on commercial lactic starters

    Directory of Open Access Journals (Sweden)

    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

  9. 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.

  10. Characterization of plasmids in a human clinical strain of Lactococcus garvieae.

    Directory of Open Access Journals (Sweden)

    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.

  11. 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.

  12. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine.

    Science.gov (United States)

    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. PMID:26981381

  13. Fate of Lactococcus lactis starter cultures during late ripening in cheese models.

    Science.gov (United States)

    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. PMID:27375251

  14. GABA Production in Lactococcus lactis Is Enhanced by Arginine and Co-addition of Malate.

    Science.gov (United States)

    Laroute, Valérie; Yasaro, Chonthicha; Narin, Waranya; Mazzoli, Roberto; Pessione, Enrica; Cocaign-Bousquet, Muriel; Loubière, Pascal

    2016-01-01

    Lactococcus lactis NCDO 2118 was previously selected for its ability to decarboxylate glutamate to γ-aminobutyric acid (GABA), an interesting nutritional supplement able to improve mood and relaxation. Amino acid decarboxylation is generally considered as among the biochemical systems allowing lactic acid bacteria to counteracting acidic stress and obtaining metabolic energy. These strategies also include arginine deiminase pathway and malolactic fermentation but little is known about their possible interactions of with GABA production. In the present study, the effects of glutamate, arginine, and malate (i.e., the substrates of these acid-resistance pathways) on L. lactis NCDO 2118 growth and GABA production performances were analyzed. Both malate and arginine supplementation resulted in an efficient reduction of acidity and improvement of bacterial biomass compared to glutamate supplementation. Glutamate decarboxylation was limited to narrow environmental conditions (pH < 5.1) and physiological state (stationary phase). However, some conditions were able to improve GABA production or activate glutamate decarboxylation system even outside of this compass. Arginine clearly stimulated glutamate decarboxylation: the highest GABA production (8.6 mM) was observed in cultures supplemented with both arginine and glutamate. The simultaneous addition of arginine, malate, and glutamate enabled earlier GABA production (i.e., during exponential growth) at relatively high pH (6.5). As far as we know, no previous study has reported GABA production in such conditions. Although further studies are needed to understand the molecular basis of these phenomena, these results represent important keys suitable of application in GABA production processes. PMID:27458444

  15. PpiA, a surface PPIase of the cyclophilin family in Lactococcus lactis.

    Directory of Open Access Journals (Sweden)

    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.

  16. Physiological adaptation of the bacterium Lactococcus lactis in response to the production of human CFTR.

    Science.gov (United States)

    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.

  17. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine.

    Science.gov (United States)

    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.

  18. Over-expressed CmbT multidrug resistance transporter improves the fitness of Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    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.

  19. Optimization of the Lactococcus lactis nisin-controlled gene expression system NICE for industrial applications

    Directory of Open Access Journals (Sweden)

    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.

  20. Food Safety: Secretome of Lactococcus lactis and Listeria monocytogenes in competition.

    Directory of Open Access Journals (Sweden)

    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”

  1. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine

    Directory of Open Access Journals (Sweden)

    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.

  2. Some chemical and physical properties of nisin, a small-protein antibiotic produced by Lactococcus lactis.

    Science.gov (United States)

    Liu, W; Hansen, J N

    1990-08-01

    Nisin is a small gene-encoded antimicrobial protein produced by Lactococcus lactis that contains unusual dehydroalanine and dehydrobutyrine residues. The reactivity of these residues toward nucleophiles was explored by reacting nisin with a variety of mercaptans. The kinetics of reaction with 2-mercaptoethane-sulfonate and thioglycolate indicated that the reaction pathway includes a binding step. Reaction of nisin at high pH resulted in the formation of multimeric products, apparently as a result of intramolecular and intermolecular reactions between nucleophilic groups and the dehydro residues. One of the nucleophiles had a pKa of about 9.8. The unique vinyl protons of the dehydro residues that give readily identifiable proton nuclear magnetic resonances were used to observe the addition of nucleophiles to the dehydro moiety. After reaction with nucleophiles, nisin lost its antibiotic activity and no longer showed the dehydro resonances, indicating that the dehydro groups had been modified. The effect of pH on the solubility of nisin was determined; the solubility was quite high at low pH (57 mg/ml at pH 2) and was much lower at high pH (0.25 mg/ml at pH 8 to 12), as measured before significant pH-induced chemical modification had occurred. High-performance liquid chromatography on a C18 column was an effective technique for separating unmodified nisin from its reaction products. The cyanogen bromide cleavage products of nisin were about 90% less active toward inhibition of bacterial spore outgrowth than was native nisin. These results are consistent with earlier observations, which suggested that the dehydro residues of nisin have a role in the mechanism of antibiotic action, in which they act as electrophilic Michael acceptors toward nucleophiles in the cellular target. PMID:2119570

  3. Detection and characterization of a bacteriocin produced by Lactococcus lactis subsp. cremoris R isolated from radish.

    Science.gov (United States)

    Yildirim, Z; Johnson, M G

    1998-04-01

    Bacteria isolated from radish were identified as Lactococcus lactis subsp. cremoris R and their bacteriocin was designated lactococcin R. Lactococcin R was sensitive to some proteolytic enzymes (proteinase-K, pronase-E, proteases, pepsin, alpha-chymotrypsin) but was resistant to trypsin, papain, catalase, lysozyme and lipase, organic solvents, or heating at 90 degrees C for 15, 30 and 60 min, or 121 degrees C for 15 min. Lactococcin R remained active after storage at -20 and -70 degrees C for 3 months and after exposure to a pH of 2-9. The molecular weight of lactococcin R was about 2.5 kDa. Lactococcin R was active against many food-borne pathogenic and food spoilage bacteria such as Clostridium, Staphylococcus, Listeria, Bacillus, Micrococcus, Enterococcus, Lactobacillus, Leuconostoc, Streptococcus and Pediococcus spp., but was not active against any Gram-negative bacteria. Lactococcin R was produced during log phase and reached a maximum activity (1600 AU ml-1) at early stationary phase. The highest lactococcin R production was obtained in MRS broth with 0.5% glucose, at 6.5-7.0 initial pH values, 30 degrees C temperature and 18-24-h incubation times. Lactococcin R adsorbed maximally to its heat-killed producing cells at pH 6-7 (95%). Crude lactococcin R at 1280 AU ml-1 was bactericidal, reducing colony counts of Listeria monocytogenes by 99.98% in 3 h. Lactococcin R should be useful as a biopreservative to prevent growth of food-borne pathogenic and food spoilage bacteria in ready-to-eat, dairy, meat, poultry and other food products. Lactococcin R differs from nisin in having a lower molecular weight, 2.5 kDa vs 3.4 kDa, and in being sensitive to pepsin and alpha-chymotrypsin to which nisin is resistant. PMID:9633097

  4. Interaction between the genomes of Lactococcus lactis and phages of the P335 species.

    Directory of Open Access Journals (Sweden)

    William John Kelly

    2013-08-01

    Full Text Available Phages of the P335 species infect Lactococcus lactis and have been particularly studied because of their association with strains of L. lactis subsp. cremoris used as dairy starter cultures. Unlike other lactococcal phages, those of the P335 species may have a temperate or lytic lifestyle, and are believed to originate from the starter cultures themselves. We have sequenced the genome of L. lactis subsp. cremoris KW2 isolated from fermented corn and found that it contains an integrated P335 species prophage. This 41 kb prophage (ΦKW2 has a mosaic structure with functional modules that are highly similar to several other phages of the P335 species associated with dairy starter cultures. Comparison of the genomes of 26 phages of the P335 species, with either a lytic or temperate lifestyle, shows that they can be divided into three groups and that the morphogenesis gene region is the most conserved. Analysis of these phage genomes in conjunction with the genomes of several L. lactis strains shows that prophage insertion is site specific and occurs at seven different chromosomal locations. Exactly how induced or lytic phages of the P335 species interact with carbohydrate cell surface receptors in the host cell envelope remains to be determined. Genes for the biosynthesis of a variable cell surface polysaccharide and for lipoteichoic acids are found in L. lactis and are the main candidates for phage receptors, as the genes for other cell surface carbohydrates have been lost from dairy starter strains. Overall, phages of the P335 species appear to have had only a minor role in the adaptation of L. lactis subsp. cremoris strains to the dairy environment, and instead they appear to be an integral part of the L. lactis chromosome. There remains a great deal to be discovered about their role, and their contribution to the evolution of the bacterial genome.

  5. Heterologous expression of Brucella abortus GroEL heat-shock protein in Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Langella Philippe

    2006-03-01

    Full Text Available Abstract Background Brucella abortus is a facultative intracellular pathogen that mainly infects cattle and humans. Current vaccines rely on live attenuated strains of B. abortus, which can revert to their pathogenic status and thus are not totally safe for use in humans. Therefore, the development of mucosal live vaccines using the food-grade lactic acid bacterium, Lactococcus lactis, as an antigen delivery vector, is an attractive alternative and a safer vaccination strategy against B. abortus. Here, we report the construction of L. lactis strains genetically modified to produce B. abortus GroEL heat-shock protein, a candidate antigen, in two cellular locations, intracellular or secreted. Results Only the secreted form of GroEL was stably produced in L. lactis, suggesting a detrimental effect of GroEL protein when intracellularly produced in this bacterium. Only trace amounts of mature GroEL were detected in the supernatant fraction of induced lactococcal cultures, and the GroEL precursor remained stacked in the cell fraction. Attempts to raise the secretion yields were made, but even when GroEL was fused to a synthetic propeptide, secretion of this antigen was not improved. Conclusion We found that L. lactis is able to produce, and to secrete, a stable form of GroEL into the extracellular medium. Despite the low secretion efficiency of GroEL, which suggest that this antigen interacts with the cell envelope of L. lactis, secretion seems to be the best way to achieve both production and protein yields, regardless of cellular location. The L. lactis strain secreting GroEL has potential for in vivo immunization.

  6. Enhancement of nisin production by Lactococcus lactis in periodically re-alkalized cultures.

    Science.gov (United States)

    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.

  7. 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.

  8. Kefir-isolated Lactococcus lactis subsp. lactis inhibits the cytotoxic effect of Clostridium difficile in vitro.

    Science.gov (United States)

    Bolla, Patricia Araceli; Carasi, Paula; Serradell, María de los Angeles; De Antoni, Graciela Liliana

    2013-02-01

    Kefir is a dairy product obtained by fermentation of milk with a complex microbial population and several health-promoting properties have been attributed to its consumption. In this work, we tested the ability of different kefir-isolated bacterial and yeast strains (Lactobacillus kefir, Lb. plantarum, Lactococcus lactis subps. lactis, Saccharomyces cerevisiae and Kluyveromyces marxianus) or a mixture of them (MM) to antagonise the cytopathic effect of toxins from Clostridium difficile (TcdA and TcdB). Cell detachment assays and F-actin network staining using Vero cell line were performed. Although incubation with microbial cells did not reduce the damage induced by C. difficile spent culture supernatant (SCS), Lc. lactis CIDCA 8221 and MM supernatants were able to inhibit the cytotoxicity of SCS to Vero cells. Fraction of Lc. lactis CIDCA 8221 supernatant containing components higher than 10 kDa were responsible for the inhibitory activity and heating of this fraction for 15 min at 100 °C completely abrogated this ability. By dot-blot assay with anti-TcdA or anti-TcdB antibodies, concentration of both toxins seems to be reduced in SCS treated with Lc. lactis CIDCA 8221 supernatant. However, protective effect was not affected by treatment with proteases or proteases-inhibitors tested. In conclusion, we demonstrated that kefir-isolated Lc. lactis CIDCA 8221 secreted heat-sensitive products able to protect eukaryotic cells from cytopathic effect of C. difficile toxins in vitro. Our findings provide new insights into the probiotic action of microorganisms isolated from kefir against virulence factors from intestinal pathogens. PMID:23217732

  9. 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 fish farming to prevent lactococcosis in rainbow trout. PMID:26307018

  10. Neutropenia crónica e infección por el virus de la inmunodeficiencia humana

    Directory of Open Access Journals (Sweden)

    Ronald A Noguera-Valverde

    2008-09-01

    Full Text Available Se presenta el caso de un paciente masculino con neutropenia crónica e infección por el virus de inmunodeficiencia humana, con una revisión de los posibles mecanismos patogénicos. Las alteraciones hematológicas como anemia, trombocitopenia y leucopenia se presentan asociadas con frecuencia a la infección aguda por el virus de inmunodeficiencia humana. Al establecer la terapia antirretroviral y disminuir la actividad del virus, estas alteraciones tienden a mejorar. Sin embargo, algunos fármacos antirretrovirales, como la zidovudina, poseen toxicidad medular y pueden producir o empeorar las alteraciones hematológicas en estos pacientes, lo cual lleva a cambios en los esquemas de tratamiento. Los citotóxicos y antimetabolitos empleados en el tratamiento de neoplasias asociadas tienen conocida actividad depresora sobre la médula ósea. Algunos antimicrobianos utilizados en la profilaxis de infecciones poseen también toxicidad hematológica conocida, como el trimetoprim-sulfametoxazol, por lo que deben ser utilizados con precaución en pacientes con infección por el virus de inmunodeficiencia humana. Por otro lado, se plantean mecanismos alternativos que causan neutropenia en estos pacientes, como la formación de anticuerpos antineutrófilos, daño primario del progenitor granulocítico, por desbalance en la producción de neutrófilos, por anticuerpos contra la glicoproteína gp120 de la cápside viral del VIH, y deficiencias vitamínicas. En el caso del paciente neutropénico febril, en quien se sospecha infección bacteriana grave, se pueden utilizar los factores estimulantes de las colonias de granulocitos para aumentar los conteos absolutos de neutrófilos y mejorar la recuperación clínica.

  11. Escova dental e dedeira na remoção da placa bacteriana dental em cães The dental brush and thumb-stall in the removal of the dental plaque in dogs

    Directory of Open Access Journals (Sweden)

    Tânia Berbert Ferreira Lima

    2004-02-01

    Full Text Available 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 a dedeira.The dental plaque is the primary factor for gingivitis formation, dental calculus, oral malodor and periodontal disease. To evaluate the amount of dental plaque removed by the dental brush and thumb-stall, 60 male and female dogs of different races, age and weight were divided in two groups and studies. The index of Logan & Boyce was used to quantify the dental plaque before and after the toothbrush. Statistical difference was observed (p 0.05 between the use of the dental brush and the thumb-stall.

  12. 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

  13. 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

  14. Cold Shock Proteins of Lactococcus lactis MG1363 Are Involved in Cryoprotection and in the Production of Cold-Induced Proteins

    NARCIS (Netherlands)

    Wouters, Jeroen A.; Frenkiel, Hélène; Vos, Willem M. de; Kuipers, Oscar P.; Abee, Tjakko

    2001-01-01

    Members of the group of 7-kDa cold-shock proteins (CSPs) are the proteins with the highest level of induction upon cold shock in the lactic acid bacterium Lactococcus lactis MG1363. By using double-crossover recombination, two L. lactis strains were generated in which genes encoding CSPs are disrupt

  15. Differential expression of proteins and genes in the lag phase of Lactococcus lactis subsp lactis grown in synthetic medium and reconstituted skim milk

    DEFF Research Database (Denmark)

    Larsen, N.; Boye, Mette; Jakobsen, Marianne;

    2006-01-01

    We investigated protein and gene expression in the lag phase of Lactococcus lactis subsp. lactis CNRZ 157 and compared it to the exponential and stationary phases. By means of two-dimensional polyacrylamide gel electrophoresis, 28 highly expressed lag-phase proteins, implicated in nucleotide meta...

  16. 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

  17. Induction of antigen-specific tolerance by oral administration of Lactococcus lactis delivered immunodominant DQ8-restricted gliadin peptide in sensitized nonobese diabetic Abo Dq8 transgenic mice

    NARCIS (Netherlands)

    I.L. Huibregtse; E.V. Marietta; S. Rashtak; F. Koning; P. Rottiers; C.S. David; S.J.H. van Deventer; J.A. Murray

    2009-01-01

    Active delivery of recombinant autoantigens or allergens at the intestinal mucosa by genetically modified Lactococcus lactis (LL) provides a novel therapeutic approach for the induction of tolerance. Celiac disease is associated with either HLA-DQ2- or HLA-DQ8-restricted responses to specific antige

  18. 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

  19. 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

  20. 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 oth...

  1. Complete Genome Sequence of Lactococcus lactis IO-1, a Lactic Acid Bacterium That Utilizes Xylose and Produces High Levels of l-Lactic Acid

    OpenAIRE

    Kato, Hiroaki; Shiwa, Yuh; Oshima, Kenshiro; Machii, Miki; Araya-Kojima, Tomoko; Zendo, Takeshi; Shimizu-Kadota, Mariko; Hattori, Masahira; Sonomoto, Kenji; Yoshikawa, Hirofumi

    2012-01-01

    We report the complete genome sequence of Lactococcus lactis IO-1 (= JCM7638). It is a nondairy lactic acid bacterium, produces nisin Z, ferments xylose, and produces predominantly l-lactic acid at high xylose concentrations. From ortholog analysis with other five L. lactis strains, IO-1 was identified as L. lactis subsp. lactis.

  2. 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...

  3. 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

    Directory of Open Access Journals (Sweden)

    D Zúñiga García

    2012-12-01

    Full Text Available 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 bien manejados y difícilmente se usan ambos. El cepillo Cross Action Pro-Salud®, se ha presentado como una alternativa simple de usar y de transportar, por ser un único cepillo que combina las caracteristicas de los dos cepillos comunmente recomendados. Para evaluar la efectividad de este cepillo, en comparación con la prescripción convencional, se evaluaron 2 grupos, de 23 pacientes cada uno, portadores de aparatología fija. Un grupo utilizó la prescripción habitual y un segundo grupo utilizó cepillo Cross Action Pro-Salud®, por un período de 45 días. Los indices de higiene de O`leary, de placa en brackets y gingival modificado fueron registrados al inicio y 45 días después del uso diario de los cepillos antes mencionados. Se utilizó test-t para comparar los resultados obtenidos y se determinó que se produjo una disminución significativa en los tres indices de higiene, no existiendo diferencias en los resultados obtenidos entre ambas prescripciones. El cepillo Oral-B Cross-Action Pro-Salud® es una alternativa recomendable, ya que permite eliminar efectivamente la placa bacteriana en pacientes ortodónticos, y al ser un único cepillo, facilita y acorta el tiempo de cepillado.Orthodontic fixed appliances include elements that allow the accumulation of bacterial plaque, making tooth brushing more difficult and increasing the risk of developing caries, white spot lesions, and periodontal disease. Several toothbrushes designs have been

  4. Antibióticos cefalos poránicos: Actualidades y perspectivas

    Directory of Open Access Journals (Sweden)

    Zalua Rodríguez-Riera

    2013-01-01

    Full Text Available Los antibióticos cefalosporánicos o cefalosporinas son los agentes antimicrobianos más indicados en la práctica médica, debido a su amplio espectro de actividad bacteriana, probada eficacia y alto perfil de seguridad. El objetivo de este trabajo consistió en brindar un panorama sobre las características principales de los antibióticos cefalosporánicos así como una actualización sobre los últimos fármacos introducidos en la clínica y las investigaciones de futuros compuestos. Como resultado se puede afirmar que recientemente, ha surgido una nueva generación de antibióticos cefalosporánicos de espectro extendido contra bacterias Gram positivas multiresistentes denominada cefalosporinas de quinta generación cuyos principales representantes son el ceftobiprol medocaril y la ceftarolina fosamil. Por otra parte, la búsqueda de nuevas cefalosporinas de acuerdo con la estrategia de obtención de antibióticos de espectro reducido contra patógenos específicos o grupos específicos de bacterias también resulta un campo de sumo interés con el objetivo de minimizar la aparición de nuevos tipos de cepas resistentes. Los antibióticos cefalosporánicos han evolucionado de generación en generación en correspondencia con el avance de los nuevos mecanismos de resistencia bacteriana que fueron surgiendo. En un inicio se basaban en el ingenio y las transformaciones estructurales empíricas realizadas por los químicos medicinales. Sin embargo, en este nuevo siglo, los estudios químico teóricos de estructura actividad en los antibióticos cefalosporánicos y su sitio de acción, han cobrado una gran importancia. El empleo de métodos de cálculo computacionales permite aproximarse, de una forma más certera, al diseño de nuevos compuestos y augura un gran futuro para el surgimiento de nuevas cefalosporinas.

  5. Efeito da nisina na contagem de Lactococcus e Lactobacillus em queijo Minas artesanal da região de Araxá - MG

    Directory of Open Access Journals (Sweden)

    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.

  6. BRONOPOL AND AZIDIOL CHEMICALS: TIME AND TEMPERATURE INFLUENCE IN THE TOTAL BACTERIAL COUNT OF RAW MILK CONSERVANTES BRONOPOL E AZIDIOL: INFLUÊNCIA DO BINÔMIO TEMPO/TEMPERATURA NA CONTAGEM BACTERIANA TOTAL DO LEITE CRU

    Directory of Open Access Journals (Sweden)

    Márcio Eduardo Pereira Martins

    2009-07-01

    do conservante bronopol em contraste ao azidiol na contagem bacteriana total (CBT em amostras de leite cru submetidas a diferentes temperaturas de armazenamento. Avaliaram-se quatro faixas de temperatura de armazenamento de amostras: T1 – 1,8 a 4,2 ºC; T2 – 6,4 a 8,3ºC; T3 – 12,1 a 14,5ºC; e T4 – 24 a 25,5ºC, em três grupos: Grupo 1 – controle sem conservante; Grupo 2 – azidiol líquido + corante azul de bromofenol; Grupo 3 – bronopol®. As amostras foram analisadas durante dez dias consecutivos, iniciando 24 horas após colhidas. Após análise por citometria de fluxo pelo equipamento BactoScan FC, consideraram-se amostras de leite cru de quatorze tanques de expansão divididas em dois níveis de contaminação do leite: <105 e >106 UFC/mL. Houve efeito do conservante bronopol pelo nível de contaminação do leite cru. O bronopol possui efeito bacteriostático em amostras de leite com CBT abaixo de 105 UFC/mL e bactericida em amostras com CBT superiores a 106 UFC/mL. A CBT obtida nas amostras de leite cru conservadas com bronopol foi inferior àquela obtida nas amostras com azidiol. Ocorreu efeito do bronopol sobre a CBT pela temperatura e pelo tempo de estocagem da amostra. O efeito bactericida do bronopol® torna inviável sua utilização em amostras de leite cru destinadas à CBT.  A eficiência do azidiol na amostra de leite cru destinada à CBT como agente bacteriostático foi dependente da menor temperatura de armazenamento da amostra, independente do nível de contaminação inicial. A amostra de leite cru destinada à CBT pode ser analisada em até uma semana depois de colhida, se for adicionada de azidiol e mantida sob refrigeração em temperatura entre 1ºC e 4 ºC.

    PALAVRAS-CHAVES: Azidiol, bronopol, contagem bacteriana, leite cru, tempo, temperatura.

  7. Heterotrophic bacteria abundances in Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil Abundância bacteriana heterotrófica na Lagoa Rodrigo de Freitas (Rio de Janeiro, Brasil

    Directory of Open Access Journals (Sweden)

    Alessandra M. Gonzalez

    2006-12-01

    " em ágar R2A. Outro objetivo foi avaliar a influência da lagoa na qualidade das águas de Ipanema e do Leblon. Dados físico-químicos também foram adquiridos. Amostras de água sub-superficiais foram coletadas mensalmente, de dezembro de 1999 a outubro de 2000. Na lagoa, a abundância de bactérias cultivadas variou de 6,9x10(5 a 5,0x10(7 UFC.100 mL-1. Em Ipanema e no Leblon, esse parâmetro atingiu 1,4x10(5 e 2,8x10(6 UFC.100 mL-1, respectivamente. A abundância bacteriana total variou de 2,9x10(7 a 3,2x10(7 células.mL-1 na lagoa. Em Ipanema e no Leblon, este parâmetro alcançou, respectivamente, 8,7x10(6 a 1,1x10(7 células.mL-1. Dois sub-grupos bacterianos foram observados nas estações, com predomínio de células HNA. Amostras foram posteriormente coletadas visando um maior entendimento sobre as bactérias presentes nesses ambientes. A abundância bacteriana foi analisada apenas por citometria em fluxo e os resultados oscilaram entre 8,3x10(6 e 2,5x10(7 células.mL-1 na lagoa. Na praia, esse parâmetro atingiu 6,9x10(6 células.mL-1. Dois sub-grupos bacterianos também foram observados, com predomínio de células HNA na lagoa e LNA na praia adjacente. Os resultados indicaram que a lagoa é um ecossistema eutrofizado, onde as bactérias e os parâmetros físico-químicos distribuem-se de modo uniforme. Os dados ainda indicaram que as águas poluídas da lagoa afetam a qualidade das praias de Ipanema e do Leblon.

  8. Osteomielitis por salmonella

    Directory of Open Access Journals (Sweden)

    Alicia Velázquez Pérez

    2014-08-01

    Full Text Available Se presenta el caso de una paciente femenina de color blanco y dos años de edad, con diagnóstico prenatal de sicklemia, que desde edades tempranas tiene problemas de la enfermedad. Ingresó en esta ocasión por una de las complicaciones infecciosas que ocasiona este padecimiento, una osteomielitis del húmero izquierdo, aislándose el germen en el hemocultivo realizado, una salmonella. Necesitó de tratamiento enérgico y prolongado; se obtuvo un resultado satisfactorio en la evolución de la enfermedad y se sigue sistemáticamente por consulta externa en la actualidad

  9. Propagación por estacas y estudio preliminar del establecimiento in vitro de granadilla (Passiflora ligularis, juss

    Directory of Open Access Journals (Sweden)

    Dora Flores

    Full Text Available La granadilla (Passiflora ligularis es una especie de polinización abierta, razón por la cual presenta un alto porcentaje de variabilidad genética. En Costa Rica este cultivo ofrece una opción de diversificación agrícola para la zona de Los Santos y El Guarco de Cartago. El uso de técnicas biotecnológicas como el cultivo de tejidos favorece la explotación de este, ya que permitiría el establecimiento de plantaciones más homogéneas que contribuirían a mejorar el rendimiento y la calidad del fruto. El objetivo de esta investigación fue establecer la metodología de propagación por estacas y realizar un estudio preliminar que conduzca al establecimiento in vitro de material. Se realizaron tres introducciones de estacas al invernadero y es empleado Agrirrot (0,01% AIB para inducir el enraizamiento; se obtuvo un 50% o más de enraizamiento y brotación de las estacas en cada introducción. Para el establecimiento in vitro se introdujeron brotes provenientes de estacas pretratadas en el invernadero. Se obtuvo un 37,5% de explantes muertos por quema, un 50% presentó contaminación fungosa, bacteriana o ambas y un 12,5% de material limpio y brotado.

  10. 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

  11. 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

  12. 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.

  13. Dermatitis canina por Malassezia

    Directory of Open Access Journals (Sweden)

    Rejas López, Juan

    2008-05-01

    Full Text Available La dermatitis por Malassezia en perros en generalmente una complicación a procesos alérgicos, seborreicos, presencia de pliegues, etc. aunque también se han descrito otras presentaciones, como la hipersensibilidad contra esta levadura. La demostración de la presencia de Malassesia pachydermatis se hace de manera sencilla mediante citología. El tratamiento de esta dermatitis puede ser tópico u oral.

  14. Dermatitis canina por Malassezia

    OpenAIRE

    Rejas López, Juan

    2008-01-01

    La dermatitis por Malassezia en perros en generalmente una complicación a procesos alérgicos, seborreicos, presencia de pliegues, etc. aunque también se han descrito otras presentaciones, como la hipersensibilidad contra esta levadura. La demostración de la presencia de Malassesia pachydermatis se hace de manera sencilla mediante citología. El tratamiento de esta dermatitis puede ser tópico u oral.

  15. Enfermedad respiratoria grave en terapia intensiva durante la pandemia por el virus de influenza A (H1N1 2009

    Directory of Open Access Journals (Sweden)

    José Aquino-Esperanza

    2010-10-01

    Full Text Available Se describen pacientes hospitalizados en una unidad de terapia intensiva por enfermedad respiratoria aguda grave con características de influenza durante los primeros meses de la pandemia por influenza A(H1N1 2009 en la Argentina. Evaluamos datos clínicos, scores de gravedad, pruebas de laboratorio, microbiología y radiología torácica al ingreso, evolución y mortalidad hospitalaria, comparando pacientes con y sin confirmación de H1N1 por test de reacción de polimerasa en cadena, transcriptasa reversa (RT-PCR. Entre junio y julio de 2009 se internaron 31 pacientes adultos con una mediana de edad de 54 años (percentilo 25-75: 33-66. Presentaron test positivo para H1N1, 17 pacientes. Tenían al menos una condición concurrente 16 pacientes. La expresión radiográfica más frecuente fue infiltrados intersticio-alveolares bilaterales en 20 casos; 5 tenían consolidación lobar unilateral. La coinfección bacteriana (aislamiento de bacterias o IgM positiva para infecciones bacterianas, se demostró en 21 pacientes. Requirieron ventilación mecánica 23 pacientes y 18 desarrollaron síndrome de distrés respiratorio agudo (SDRA. La linfopenia y elevación de creatinina-fosfoquinasa fue frecuente (83% y 65%, respectivamente. Los 6 pacientes que murieron (19% eran mayores de 75 años o tenían cáncer o inmunodepresión. El tratamiento antiviral temprano (≤ 48 horas se asoció a menor necesidad de ventilación mecánica (54% vs. 89%; p: 0.043. No hubo diferencia significativa en las variables analizadas entre el grupo H1N1 positivo y el negativo, lo que sugiere tener igual enfoque terapéutico frente a una epidemia. La infección por H1N1 determinó falla respiratoria aguda y SDRA. La mortalidad ocurrió en pacientes añosos o con co-morbilidades graves.

  16. causada por Fusarium moniliforme

    Directory of Open Access Journals (Sweden)

    Mariano Mendoza Elos

    2006-01-01

    Full Text Available El objetivo de éste trabajo fue determinar la resistencia horizontal de 134 líneas S1 de maíz al hongo Fusarium moniliforme. La enfermedad fue inducida mediante inoculación en la etapa de floración masculina bajo condiciones de campo utilizando la técnica del palillo. Las líneas se evaluaron en México en 2002. La estimación de la enfermedad se hizo en dos ocasiones con una separación de 20 días. Las evaluaciones mostraron que las líneas Roque-801, 804, 1103 y 1405 fueron resistentes en la primera evaluación. Las tasas de incremento de la enfermedad variaron de 0,01 a 0,229 por unidad por día. Las líneas mostraron bajos niveles de enfermedad de 0 a 1 % en la primera evaluación. En la segunda evaluación, los niveles de enfermedad variaron de 49 a 100 %. En un programa de mejoramiento genético estas líneas pueden ser utilizadas para mejorar la resistencia horizontal del maíz a la pudrición del tallo causada por Fusarium moniliforme

  17. Engineering the cell surface display of cohesins for assembly of cellulosome-inspired enzyme complexes on Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    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

  18. 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.

  19. Miotoxicidade por organofosforados

    Directory of Open Access Journals (Sweden)

    Cavaliere Maria J.

    1996-01-01

    Full Text Available Os organofosforados são um grupo de compostos químicos amplamente utilizados em agropecuária como inseticidas, ocasionando intoxicações acidentais em animais e humanos, e mesmo sendo utilizados em tentativas de suicídio. A toxicidade desses produtos decorre sobretudo de insuficiência cárdio-respiratória por compromentimento do sistema nervoso autônomo. Sabe-se que alguns destes compostos induzem em animais de experimentação e em humanos, uma miopatia caracterizada por degeneração de células musculares, comprometendo sobretudo a musculatura respiratória. Baseado no fato de que este comprometimento contribui para a piora da função respiratória, propõe-se um protocolo de avaliação rotineira de miotoxicidade por compostos organofosforados, através de uma bateria mínima e suficiente de colorações e reações histoquímicas para quantificação da necrose muscular. Utilizaram-se como modelo experimental, grupos de ratos albinos (Wistar intoxicados com o organofosforado paraoxon, com e sem antídotos (atropina ou pralidoxima. Verificou-se nos grupos tratados com paraoxon e paraoxon mais atropina, necrose de fibras musculares no diafragma, que atingia em determinadas áreas até 15% das fibras. No grupo tratado com paraoxon mais pralidoxima, a necrose foi mínima, evidenciando o papel mioprotetor deste último antídoto.

  20. Avaliação da contaminação bacteriana em desinfetantes de uso domiciliar

    Directory of Open Access Journals (Sweden)

    Miyagi Fumie

    2000-01-01

    Full Text Available OBJETIVO: Avaliar desinfetantes de uso domiciliar, identificando a presença de bactérias contaminantes, e conhecer o nível de tolerância dessas bactérias ao cloreto de benzalcônio. MÉTODOS: Foram adquiridas aleatoriamente no comércio da região metropolitana de São Paulo, SP, Brasil, 52 amostras de desinfetantes de uso domiciliar para análise quanto à presença de bactérias contaminantes. O nível de tolerância dessas bactérias ao cloreto de benzalcônio foi determinado pelo método da macrodiluição em caldo. RESULTADOS: De 52 amostras, 16 (30,77% estavam contaminadas por bactérias Gram negativas, com contagens variando entre 10(4 e 10(6 UFC/ml. Esses contaminantes foram identificados como Alcaligenes xylosoxidans, Burkholderia cepacia e Serratia marcescens. As Concentrações Inibitórias Mínimas (CIM: mg/ml do cloreto de benzalcônio para S. marcescens, A. xylosoxidans e B. cepacia foram: 2,48, 1,23 e 0,30, respectivamente. CONCLUSÕES Os desinfetantes de uso domiciliar à base de compostos de amônio quaternário são passíveis de contaminação por bactérias. As CIM do cloreto de benzalcônio para as bactérias contaminantes estavam abaixo das concentrações do princípio ativo presente nos desinfetantes, indicando que a tolerância ao biocida não é estável, podendo ser perdida com o cultivo das bactérias em meios de cultura sem o biocida.

  1. Avaliação da contaminação bacteriana em desinfetantes de uso domiciliar

    Directory of Open Access Journals (Sweden)

    Fumie Miyagi

    2000-10-01

    Full Text Available OBJETIVO: Avaliar desinfetantes de uso domiciliar, identificando a presença de bactérias contaminantes, e conhecer o nível de tolerância dessas bactérias ao cloreto de benzalcônio. MÉTODOS: Foram adquiridas aleatoriamente no comércio da região metropolitana de São Paulo, SP, Brasil, 52 amostras de desinfetantes de uso domiciliar para análise quanto à presença de bactérias contaminantes. O nível de tolerância dessas bactérias ao cloreto de benzalcônio foi determinado pelo método da macrodiluição em caldo. RESULTADOS: De 52 amostras, 16 (30,77% estavam contaminadas por bactérias Gram negativas, com contagens variando entre 10(4 e 10(6 UFC/ml. Esses contaminantes foram identificados como Alcaligenes xylosoxidans, Burkholderia cepacia e Serratia marcescens. As Concentrações Inibitórias Mínimas (CIM: mg/ml do cloreto de benzalcônio para S. marcescens, A. xylosoxidans e B. cepacia foram: 2,48, 1,23 e 0,30, respectivamente. CONCLUSÕES Os desinfetantes de uso domiciliar à base de compostos de amônio quaternário são passíveis de contaminação por bactérias. As CIM do cloreto de benzalcônio para as bactérias contaminantes estavam abaixo das concentrações do princípio ativo presente nos desinfetantes, indicando que a tolerância ao biocida não é estável, podendo ser perdida com o cultivo das bactérias em meios de cultura sem o biocida.

  2. Por mil devaluados pesos

    Directory of Open Access Journals (Sweden)

    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  3. Transfer of nisin gene cluster from Lactococcus lactis ATCC 11454 into the chromosome of Bacillus subtilis 168.

    Science.gov (United States)

    Yuksel, Sahru; Hansen, J Norman

    2007-03-01

    Nisin is an antimicrobial peptide produced by certain strains of Lactococcus lactis. It is a gene-encoded peptide that contains unusual amino acid residues. These novel residues are introduced by posttranslational modification machinery and confer unique chemical and physical properties that are not attainable by regular amino acid residues. To study the modification mechanisms and to create structural analogs with superior properties, it would be advantageous to insert the nisin genes into a bacterial strain that is amenable to genetic manipulation. In this study, we report the cloning and integration of the complete and intact nisin gene cluster into the Bacillus subtilis 168 chromosome. Furthermore, we demonstrate that the nisin genes are transcriptionally active. These results should greatly facilitate the studies of the genes and proteins involved in nisin expression, as well as provide a standard system for the manipulation and expression of genes involved in other members of the lantibiotic family of antimicrobial peptides. PMID:17143619

  4. 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. PMID:23688550

  5. Mdt(A), a New Efflux Protein Conferring Multiple Antibiotic Resistance in Lactococcus lactis and Escherichia coli

    Science.gov (United States)

    Perreten, Vincent; Schwarz, Franziska V.; Teuber, Michael; Levy, Stuart B.

    2001-01-01

    The mdt(A) gene, previously designated mef214, from Lactococcus lactis subsp. lactis plasmid pK214 encodes a protein [Mdt(A) (multiple drug transporter)] with 12 putative transmembrane segments (TMS) that contain typical motifs conserved among the efflux proteins of the major facilitator superfamily. However, it also has two C-motifs (conserved in the fifth TMS of the antiporters) and a putative ATP-binding site. Expression of the cloned mdt(A) gene decreased susceptibility to macrolides, lincosamides, streptogramins, and tetracyclines in L. lactis and Escherichia coli, but not in Enterococcus faecalis or in Staphylococcus aureus. Glucose-dependent efflux of erythromycin and tetracycline was demonstrated in L. lactis and in E. coli. PMID:11257023

  6. 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.

  7. 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.

  8. Multi-stress resistance in Lactococcus lactis is actually escape from purine-induced stress sensitivity

    DEFF Research Database (Denmark)

    Ryssel, Mia; Hviid, Anne-Mette Meisner; Dawish, Mohamed S.;

    2014-01-01

    to the acid-stress medium increased the stress sensitivity of L. lactis MG1363. It is also shown that high intracellular guanine nucleotide pools confer increased sensitivity to high temperatures, thus showing that it is indeed a multi-stress phenotype. Our analysis suggests that an increased level......Multi-stress resistance is a widely documented and fascinating phenotype of lactococci where single mutations, preferentially in genes involved in nucleotide metabolism and phosphate uptake, result in elevated tolerance to multiple stresses simultaneously. In this report, we have analysed the...... metabolic basis behind this multi-stress-resistance phenotype in Lactococcus lactis subsp. cremoris MG1363 using acid stress as a model of multi-stress resistance. Surprisingly, we found that L. lactis MG1363 is fully resistant to pH 3.0 in the chemically defined SA medium, contrary to its sensitivity in...

  9. Diversidade e potencial biotecnológico da comunidade bacteriana endofítica de sementes de soja Diversity and biotechnological potential of endophytic bacterial community of soybean seeds

    Directory of Open Access Journals (Sweden)

    Laura de Castro Assumpção

    2009-05-01

    Full Text Available O objetivo deste trabalho foi isolar, caracterizar e identificar a comunidade bacteriana endofítica de sementes de soja e avaliar o seu potencial biotecnológico. Foram utilizadas sementes de 12 cultivares de soja. Os isolados bacterianos endofíticos obtidos foram avaliados in vitro quanto ao antagonismo a fungos fitopatogênicos, síntese de ácido indolacético (AIA e solubilização de fosfato. A caracterização foi realizada com técnicas de isolamento, análise de restrição do DNA ribossomal amplificado (ARDRA e sequenciamento parcial do gene 16S rDNA. Os isolados com maior potencial biotecnológico foram inoculados em sementes de soja, para se avaliar a capacidade de promoção de crescimento de plantas. Foi possível identificar 12 ribótipos por meio da ARDRA, que foram classificados como: Acinetobacter, Bacillus, Brevibacterium, Chryseobacterium, Citrobacter, Curtobacterium, Enterobacter, Methylobacterium, Microbacterium, Micromonospora, Pantoea, Paenibacillus, Pseudomonas, Ochrobactrum, Streptomyces e Tsukamurella. Quanto ao potencial biotecnológico da comunidade, 18% dos isolados controlaram o crescimento de fungos fitopatogênicos, 100% produziram AIA, e 39% solubilizaram fosfato. O isolado 67A(57 de Enterobacter sp. aumentou significativamente a massa de matéria seca da raiz. A inoculação de isolados com elevado potencial biotecnológico em avaliações in vitro não promoveu o crescimento de plantas de soja na maioria dos casos.The objectives of this work were to isolate, characterize and identify the endophytic bacterial community of soybean seeds, and to test the biotechnological potential of this community. Seeds from 12 soybean cultivars were used. The endophytic bacterial isolates were evaluated for in vitro antagonism against phytopathogenic fungi, synthesis of indoleacetic acid (IAA, and capacity to solubilize phosphate. Isolation techniques, amplified ribosomal DNA restriction analysis (ARDRA grouping, and

  10. Peritonite bacteriana espontânea na cirrose hepática: prevalência, fatores preditivos e prognóstico Spontaneous bacterial peritonitis in hepatic cirrhosis: prevalence, predictive factors and prognosis

    Directory of Open Access Journals (Sweden)

    F.A.F. Figueiredo

    1999-04-01

    Full Text Available OBJETIVO: Investigar prevalência, fatores preditivos e prognóstico dos episódios de Peritonite Bacteriana Espontânea (PBE na cirrose hepática. METODOLOGIA: Estudamos, prospectivamente, 143 pacientes com cirrose hepática, ambulatoriais ou internados, que foram atendidos nos Serviços de Clínica Médica do HUCFF e de Gastroenterologia do HUPE no período de janeiro/95 a janeiro/96. Estes pacientes foram submetidos a questionário, exame físico, colheita de sangue e paracentese abdominal com colheita de líquido ascítico (LA e, então, acompanhados por um período médio de 4 meses, onde a taxa de mortalidade foi determinada. RESULTADOS: A prevalência de PBE foi cerca de 20%, sendo 24% PBE cultura positiva, 66% Ascite Neutrofílica cultura negativa e 10% Bacterioascite. Na análise univariada, alcançaram significância estatística (p=0.05 como fatores preditivos do episódio de PBE: HGI na semana anterior; passado de encefalopatia hepática; classificação de Child; dosagens séricas de proteínas, albumina, C3, C4 e uréia; dosagens no LA de C3 e C4. Após serem introduzidas na análise multivariada, apenas HGI na semana anterior, albumina sérica e C4 do LA foram independentemente correlacionadas ao episódio de PBE (p=0.05. A mortalidade hospitalar e durante o acompanhento foi de 33,3% e 53,8% para o grupo com PBE; 8,5% e 31,9% para o grupo sem PBE; respectivamente (p=0.01 e p=0.04. A probabilidade cumulativa de sobrevida foi significativamente menor no grupo com PBE. CONCLUSÕES: A PBE é uma complicação freqüente, depende, principalmente, da gravidade da doença hepática e é um marcador de prognóstico desfavorável nos pacientes com cirrose hepática.BACKGROUND: Spontaneous Bacterial Peritonitis (SBP is a common and potentially fatal complication of cirrhosis. Multiple variants of this infection have been described during the past decade. Few studies have investigated SBP in Brazil. MATERIAL AND METHOD: In order to

  11. Aerobic bacterial microflora of Broad-snouted caiman (Caiman latirostris oral cavity and cloaca, originating from Parque Zoológico Arruda Câmara, Paraíba, Brazil Microflora bacteriana aeróbica da cavidade oral e cloaca de jacaré-de-papo-amarelo (Caiman latirostris procedentes do Zoológico de João Pessoa, PB, Brasil

    Directory of Open Access Journals (Sweden)

    J.S.A. Silva

    2009-03-01

    Full Text Available The objective of this study was to isolate and identify the aerobic bacterial microflora from the oral cavity mucosa and cloaca's samples, collected from Broad-snouted caiman (Caiman latirostris, born and bred in captivity at Parque Zoológico Arruda Câmara, João Pessoa, Paraíba, Brazil. The most common bacteria were Staphylococcus sp. (14.74%, Corynebacterium sp. (13.68%, Escherichia coli (13.68% and Shigella sp. (11.58%, and the less common were Citrobacter sp. (1.05%, Klebsiella pneumoniae (1.05% and Salmonella sp. (1.05%.This emphasizes the importance of these microorganisms' participation in infectious processes (sepsis and injuries caused by crocodilians.O presente estudo teve como objetivo isolar e identificar a microflora bacteriana aeróbica presente na mucosa da cavidade oral e da cloaca de exemplares de jacarés-de-papo-amarelo (Caiman latirostris nascidos e criados em cativeiro no Parque Zoológico Arruda Câmara, localizado na cidade de João Pessoa - PB. As bactérias mais freqüentes foram Staphylococcus sp. (14,74%, Corynebacterium sp.(13,68%, Escherichia coli (13,68% e Shigella sp. (11,58%, e as menos prevalentes foram Citrobacter sp.(1,05%, Klebsiella pneumoniae (1,05% e Salmonella sp. (1,05%. Ressalta-se a importância da participação desses microrganismos em processos infecciosos (septicemias e em feridas provocadas por crocodilianos.

  12. The clinicopathological and epidemiological aspects of bacterial endocarditis in dogs: 28 cases (2003-2008 / Aspectos clínico-patológicos e epidemiológicos da endocardite bacteriana em cães: 28 casos (2003-2008

    Directory of Open Access Journals (Sweden)

    Patrícia Mendes Pereira

    2010-04-01

    Full Text Available The aim of this study was to review the clinicopathological aspects and report the data obtained from bacterial endocarditis cases in dogs. A restropective study was carried out based on files of the Veterinary Hospital and the Animal Pathology Laboratory of Universidade Estadual de Londrina (UEL from January 2003 to may 2008. During this period, 28 dogs presented bacterial endocarditis, 50% males and 50% females. Medium to large dogs were the most affected and adult animals were prevalent, with the following clinical signs: apathy, hiporexy, hyperthermia, splenomegaly, dyspnea, dehydration, dysuria and cardiac murmur, Necropsy revealed the mitral valve as the most affected cardiac structure and among the organs, the kidneys were the most affected.O presente trabalho objetivou revisar os aspectos clínico-patológicos e relatar os dados obtidos sobre a endocardite bacteriana em cães, por meio de estudo retrospectivo realizado nos arquivos do Hospital Veterinário e Laboratório de Patologia Animal da Universidade Estadual de Londrina (UEL, durante o período de janeiro de 2003 a maio de 2008. No transcorrer do período considerado, 28 cães apresentaram a doença, sendo 50% machos e 50% fêmeas. Animais de médio a grande porte foram os mais acometidos e os adultos obtiveram prevalência. Os principais sinais clínicos apresentados foram apatia, hiporexia, hipertermia, esplenomegalia, dispnéia, desidratação, disúria e sopro cardíaco. À necropsia, observou-se que a válvula mitral foi a estrutura cardíaca mais afetada, sendo o rim o órgão mais frequentemente acometido.

  13. Hiperinfestação por Strongyloides Stercoralis - doi:10.5020/18061230.2006.p118

    Directory of Open Access Journals (Sweden)

    Tânia Maria Cavalcante Maia

    2012-01-01

    Full Text Available A estrongiloidíase é uma helmintíase predominantemente intestinal causada pelo Strongyloides stercoralis, sendo o homem seu hospedeiro definitivo, além da principal fonte de infecção. Este trabalho objetivou relatar um caso de identificação laboratorial de larva de Strongyloides stercolaris no líquido ascítico de um paciente do sexo masculino, 49 anos, agricultor, etilista há mais de 30 anos, encaminhado ao Hospital Universitário Walter Cantídio, por estar evoluindo com episódios de icterícia associada a aumento do volume abdominal diagnosticado como ascite, vômito, diarréia pastosa e diminuição do volume urinário. No internamento, foi iniciada medicação profilática para Peritonite Bacteriana Espontânea (PBE, bem como reposição de vitaminas, hidratação venosa e diuréticos, sem sucesso terapêutico. A partir de achados no líquido ascítico de presença de larvas de Strongyloides stercolaris em atividade, o quadro foi interpretado como estrongiloidíase disseminada em paciente imunocomprometido por hepatopatia avançada e alcoólica. O paciente evoluiu com quadro de choque caracterizado por hipotensão e hipotermia, tendo chegado a fazer uso de drogas vasoativas de forma não responsiva. O quadro evoluiu para óbito. Os autores chamam a atenção para a importância do diagnóstico e tratamento precoce da estrongiloidíase, principalmente em pacientes imunodeprimidos.

  14. Resistencia bacteriana a antibióticos en el Hospital San Juan de Dios, 1995-1999

    Directory of Open Access Journals (Sweden)

    Ricardo Boza-Cordero

    2001-07-01

    Full Text Available Justificación: La resistencia a antibióticos por parte de bacterias patógenas es un grave problema mundial. Su control ha sido difícil pero deben hacerse todos los esfuerzos por realizarlo. Conocer la epidemiología en las diferentes regiones y países se constituye en parte importante de este control. Este estudio se llevóa cabo con el fin de analizar el comportamiento de la resistencia en el hospital San Juan de Dios, centro de atención nacional de adultos de aproximadamente 700 camas. Materiales y métodos: El estudio se basóen los datos obtenidos en los años 1995-1999 ya que en 1995 se inició el empleo de equipo automatizado VITEK® en este hospital. Se analizaron 2817 aislamientos de cocos Gram positivos (CGP y 7626 de bacilos Gram negativos (BGN obtenidos de todos los sitios anatómicos y fluidos corporales. Por ser un estudio retrospectivo, no se pudo definir cuáles aislamientos provenían de infecciones intra o extrahospitalarias. Resultados: Staphylococcus aureus fue el CGP más frecuentemente aislado, mientras que el BGN más frecuente fue Escherichia coli. En más de 90% de los estafilococos aislados se demostróresistencia a la penicilina. La resistencia a la oxacilina en S.aureus se incrementóde 35% en 1995 a 52% en 1999 mientras que en los estafilococos coagulasa negativa, pasóde 70 a 77% en el mismo periodo. La resistencia a la cefalotina en S.aureus pasóde 35 a 50% mientras que en los estafilococos coagulasa negativa pasóde 65 a 76%. La resistencia a la clindamicina en ambos grupos bacterianos se mantuvo relativamente estable. No se demostróresistencia a la vancomicina. La mayoría de los enterococos aislados correspondieron a E. faecalis, 75% de ellos fueron sensibles a la penicilina y 50% no mostraron sinergismo de la gentamicina con los antibióticos que actúan sobre la pared. No se encontraron enterococos vancomicina resistentes. En las enterobacterias se observó un aumento importante de la resistencia a

  15. Advances in diagnostic tests for bacterial STDs Avances en las pruebas diagnósticas de ETS bacterianas

    Directory of Open Access Journals (Sweden)

    Stephen A Morse

    2003-01-01

    Full Text Available Because of their asymptomatic nature and nonspecific symptoms, laboratory tests are often required to diagnose a sexually transmitted infection. Over the past few years, there have been advances in technology, such as the development of nucleic acid amplification assays, which have improved our ability to diagnose infections caused by Chlamydia trachomatis. The finding that nucleic acid amplification tests can detect more infected individuals and are useful in screening low prevalence populations, has led to the development of strategies designed to reduce the cost of these assays without significantly impacting their sensitivity. The development of new tests for the diagnosis of syphilis has gained momentum from the report of a synthetic VDRL antigen, which will result in better nontreponemal antibody tests for syphilis. In spite of the completion of the genome sequence of Treponema pallidum and its annotation, we are still unable to cultivate this microorganism in vitro. However, the molecular revolution has resulted in the development of PCR assays for detecting Treponema pallidum in various types of clinical specimens, and to the production of recombinant antigens for use in tests that detect treponemal-specific antibodies. Further research will improve the availability of low cost, sensitive tests for the diagnosis of sexually transmitted infections.Las pruebas de laboratorio son necesarias a menudo para el diagnóstico de las infecciones transmitidas sexualmente, debido a la naturaleza asintomática o a la presencia de síntomas inespecíficos de esas infecciones. En este sentido, durante los años relativamente recientes se han registrado importantes avances tecnológicos, como por ejemplo los ensayos de amplificación de ácidos nucleicos que han permitido una mejora en la posibilidad de diagnosticar las infecciones causadas por Chlamydia trachomatis. El descubrimiento de que las pruebas de amplificación de ácidos nucleicos permiten

  16. Efeito de glyphosate e imazaquin na comunidade bacteriana do rizoplano de soja (Glycine max (L. Merrill e em características microbiológicas do solo Effect of glyphosate and imazaquin on the soybean rhizoplane bacterial community and microbiological soil characteristics

    Directory of Open Access Journals (Sweden)

    Jerri Édson Zilli

    2008-04-01

    Full Text Available Práticas culturais, como a aplicação de agrotóxicos, podem interferir diretamente na comunidade microbiana do solo e naquela associada às raízes vegetais. Os efeitos, no entanto, são complexos e, na maioria das vezes, de difícil detecção, quando se utilizam técnicas convencionais na avaliação. Por outro lado, o recente desenvolvimento e utilização de métodos moleculares, baseados no DNA, têm permitido melhorar a avaliação desses efeitos muitas vezes negativos. Este trabalho teve como objetivo avaliar alterações provocadas pela aplicação de herbicidas à base de glyphosate e imazaquin no C da biomassa microbiana do solo (C-BMS, respiração basal do solo (RBS e quociente metabólico (qCO2, bem como na comunidade bacteriana associada ao rizoplano de soja (Glycine max (L. Merril, por meio das técnicas de eletroforese em gel com gradiente desnaturante (DGGE e análise da região espaçadora intergênica ribossomal (RISA. Realizou-se um experimento em casa de vegetação com solo coletado em área com histórico de cultivo de soja e aplicação desses herbicidas. A C-BMS, RBS e qCO2 foram avaliadas antes da aplicação dos herbicidas e aos 2, 14, 30 e 62 dias depois desta. A comunidade bacteriana associada ao rizoplano de soja foi avaliada por DGGE e RISA aos 14, 30 e 62 dias após a aplicação dos herbicidas. Os resultados mostraram que ambos os herbicidas não ocasionaram alterações significativas no teor de C da biomassa microbiana do solo, na respiração basal do solo e no quociente metabólico; contudo, ocasionaram alterações na comunidade bacteriana associada ao rizoplano de soja, na forma de restrição do crescimento de determinadas bactérias e estímulo de outras, em todas as coletas realizadas. As similaridades entre os perfis bacterianos os tratamentos com herbicidas e o controle foram inferiores a 55 % em todas as coletas.Cultural practices, such as herbicide application, can directly interfere with

  17. Pasteurización de calostro: efecto sobre la carga bacteriana y la concentración de inmunoglobulinas G.

    Directory of Open Access Journals (Sweden)

    Jorge A. Elizondo-Salazar

    2008-09-01

    Full Text Available La pasteurización de calostro a nivel de finca ha recibido una considerable atención en los últimos años, con el fin de reducir agentes patógenos bacterianos. La adopción de esta práctica a nivel de finca ha reportado resultados significativos en la salud de las terneras y en los ingresos económicos de los productores. Sin embargo, existe poca información con respecto al efecto que tiene la pasteurización sobre la concentración de inmunoglobulinas G (IgG. Por esta razón, se llevó a cabo una investigación con el objetivo de determinar el efecto de la pasteurización (baja temperatura-largo tiempo sobre el nivel bacterial y la concentración de IgG en calostro bovino. Se colectó calostro de primer ordeño de 28 vacasHolstein. Cada muestra se agitó completamente y dos sub-muestras de 10- mL fueron analizadas. La primera sub-muestra sirvió como control mientras que la segunda fue calentada a 62.8 °C por 30 min. Las muestras de calostro tratadas y sin tratar fueron analizadas para determinar el conteo estándar de placa (CEP, conteo preliminar de incubación (CPI, conteo de coliformes (CC, conteo de no-coliformes (CNC, conteo de estreptococos ambientales (CEA y conteo de Staphylococcus aureus (CSA. Las concentraciones de IgG1 e IgG2 fueron medidas utilizando la técnica de inmunodifusión radial. Los resultados del estudio mostraron que la pasteurización tuvo como resultado una reducción significativa (P < 0.01 en los niveles de CEP, CC, CNC, CEA y CSA. La pasteurización tuvo también como resultado la desnaturalización del 14% de las IgG totales en elcalostro.

  18. Factores para el escalado del proceso de producción de celulosa por fermentación estática

    Directory of Open Access Journals (Sweden)

    Luis Alfonso Caicedo

    2011-03-01

    Full Text Available En la producción de celulosa bacteriana por el método estático, el factor de rendimiento Yp/s es afectado por la concentración de glucosa inicial y el tiempo de fermentación. Bajas concentraciones dan valores altos de Yp/s al inicio de la fermentación, mientras que altas concentraciones requieren tiempos largos para lograr valores comparables. El área superficial aumenta la producción de celulosa, pero existe una relación (área interfacial/volumen de medio límite a partir de la cual la celulosa producida por unidad de área comienza a descender. Existe una relación lineal entre el espesor relativo de película, definido como (altura de película húmeda/altura de líquido, y el área por unidad de volumen de medio. El espesor relativo límite (altura de película = altura de líquido se encontraría para una relación área- volumen teórica de 1,1 cm-1, pero en la práctica se determinó que este valor es de 0,8 cm-1 para no afectar el rendimiento de celulosa.

  19. Resistencia bacteriana a los antibióticos en la Unidad de Cuidados Intensivos, Hospital de Caldas, 1992-1994.

    Directory of Open Access Journals (Sweden)

    Eduardo León Jaramillo V.

    2009-09-01

    Full Text Available Se describe y analiza el comportamiento de los microorganismos más frecuentes en la Unidad de Cuidados Intensivos (UCI, del Hospital de Caldas (HC, y su sensibilidad/resistencia a los antibióticos, según los antibiogramas hechos por el laboratorio clínico del HC, entre 1992 y 1994. Enterobacter aerogenes fue el germen más común en la UCI. Staphylococcus dnasa negativo presentó frecuencia creciente, a través de los años del estudio. La UCI aportó 39.6% de Pseudomonas del HC. El germen más frecuente en líquido peritoneal, secreciones traqueobronquiales y orina, fue E. aerogenes; en las puntas de los catéteres venosos, Staphylococcus dnasa negativo; y, en los tubos de tórax, P. aeruginosa. La resistencia a los antibióticos en la UCI fue casi el doble a la de otros servicios del HC. Las cepas de estafilococos meticilino resistentes, en la UCI, superan 60% y empiezan a aparecer cepas resistentes a la vancomicina. Pseudomonas aeruginosa fue muy resistente tanto a los antibióticos tradicionales como a los modernos antipseudomonas. Imipenem fue el antibiótico más eficaz contra Gram negativos aerobios, incluida P. aeruginosa.

  20. Ojo por ojo

    OpenAIRE

    Ramón del Llano Ibáñez

    2011-01-01

    Nuestro pan y café de la mañana se acompaña de noticias alrededor de ejecuciones, de fosas clandestinas, de batallas del ejército, de balaceras en las calles y civiles caídos por balas perdidas : la muerte acompaña nuestro desayuno. Las calaveras de azúcar del día de muertos hoy son calaveras reales y amargas : 40 000 muertos en cuatro años después que el Presidente Calderón declaró la guerra a los narcotraficantes. Se han apresado a varios e importantes miembros de los cárteles : pero han si...

  1. Sepsis por shigella flexneri

    Directory of Open Access Journals (Sweden)

    César Cabrera C

    2005-04-01

    Full Text Available Se presenta un caso raro de sepsis por Shigella flexneri en una paciente de 45 años de edad quien estando hospitalizada para el estudio de un tumor cerebral, requirió el uso de manitol y dosis altas de corticoides; luego de ello presenta deposiciones líquidas con moco y sangre, desarrolla síndrome de respuesta inflamatoria sistémica, luego se aísla Shigella flexneri en el hemocultivo; recibió tratamiento antibiótico con ciprofloxacina. Se describen las características del caso y se comenta de acuerdo con la revisión de literatura.

  2. Onicomicosis por hongos fuliginosos

    Directory of Open Access Journals (Sweden)

    Ingrid Salas-Campos

    2009-12-01

    Full Text Available Justificación y objetivo: Las infecciones de las uñas producidas por hongos son un problema de frecuente consulta dermatológica. Los dermatofitos son la mayor causa de estas infecciones, siendo Trichophyton rubrum el agente etiológico más importante. Sin embargo, los hongos no dermatofitos, tanto hialinos como fuliginosos, pueden ser también responsables de estos cuadros clínicos. Debido a que estos hongos tienden a ser resistentes a los antimicóticos comúnmente usados para tratar las onicomicosis, es que se hace indispensable que el clínico se asegure por medio de un examen de laboratorio de la etiología de la infección. Métodos: Se estudiaron tres casos de pacientes con lesiones en uñas, que acudieron al laboratorio de Micología Médica, Facultad de Microbiología, Universidad de Costa Rica. Se realizaron los análisis de rutina para aislamiento e identificación de hongos patógenos. Resultados: En los tres casos estudiados se observó al examen directo micelio fuliginoso. En uno de los casos se aisló e identificó Scytalidium dimidiatum, hongo que presenta resistencia a los antifúngicos utilizados para tratar onicomicosis. Conclusión. El reporte de hongos diferentes a los dermatofitos como agentes etiológicos de onicomicosis es importante para que el médico pueda elegir el tratamiento más recomendado para este tipo de infección.

  3. Motivado por cirujanos

    Directory of Open Access Journals (Sweden)

    Carlos Salazar-Vargas

    2010-12-01

    Full Text Available Comenzaba la década de los 60 y nuestro grupo nerviosamente iniciaba lecciones en los hospitales de San José. En aquellos años, el estudiante de medicina empezaba su contacto con pacientes, por lo menos 1 ó 2 años después de iniciada la carrera. El estudio del ser humano normal que ya habíamos concluido, continuaba con el del enfermo, y más adelante aprenderíamos el tratamiento. La enfermedad descrita en el libro, de pronto se convertía en un enfermo, y es a este quien hoy veíamos, cohibido pero inquisidor, en la cama de un hospital. Los profesores nos enseñaban a interrogar y a examinar a los pacientes, y cada gesto suyo, cada pregunta, cada maniobra, eran celosamente guardados en la memoria de los educandos. Con claridad percibíamos, aun a temprana edad, las diferencias entre los especialistas, y casi de manera involuntaria, cada quien iba tomando partido y escogía su futuro camino. Fue durante esos tempranos años, cuando mi vida se cruzó con la de 7 maravillosas personas y excelentes cirujanos, que marcaron para siempre mi destino y, sin quererlo ellos, me hicieron inclinarme por la cirugía. Dos eran serios y profundamente académicos: el Dr. Manuel Aguilar Bonilla y el Dr. Vesalio Guzmán Calleja; 3, decididos, incansables y muy hábiles: el Dr. Longino Soto Pacheco, el Dr. Claudio Orlich Carranza y el Dr. Carlos Prada Díaz, y 2, abordables, prácticos, joviales y amistosos: el Dr. Fernando Valverde Soley y el Dr. Randall Ferris Iglesias….

  4. Estudo da transmigração bacteriana na apendicite experimental em coelhos A study about bacterial transmigration in experimental Appendicitis in rabbits

    Directory of Open Access Journals (Sweden)

    ECF RAMOS

    2000-01-01

    Full Text Available Introdução: A queda extrínseca dos mecanismos de defesa de um hospedeiro é vista classicamente como uma infecção, que resulta na aquisição de um tecido normal, de um novo microorganismo, cuja virulência é fundamental para a sua patogenia.Na década de 50, estudos comprovaram que bactérias e endotoxinas podem ultrapassar a barreira intestinal e atingir a circulação, demonstrando ainda, que a flora intestinal representa uma importante fonte para o desenvolvimento da infecção sistêmica. Objetivo: o presente estudo visa avaliar a ocorrência de transmigração bacteriana em apendicite experimental induzida em coelhos, mediante a oclusão completa do apêndice vermiforme. Métodos: foram utilizados 24 coelhos brancos, da linhagem Nova Zelândia, com peso corporal variando de 2500 a 3000 gramas, sendo então divididos em 2 grupos. Os animais do Grupo I foram submetidos a laparotomia mediana e retirada de fragmentos do baço, rim esquerdo, pulmão direito, linfonodo abdominal, conteúdo da luz do apêndice vermiforme e sangue da veia porta para cultura. Os animais do Grupo II foram submetidos a laparotomia mediana e oclusão completa do apêndice vermiforme para a indução de apendicite e, após 24 horas, realizada a coleta do material nos moldes do Grupo I. Resultados: No Grupo controle (Grupo I, não se observou o crescimento de bactérias nas amostras analisadas. No Grupo experimento (Grupo II, observou-se o crescimento de Escherichia coli em todos os animais. Conclusão: Ocorreu transmigração bacteriana após 24 horas de observação em coelhos com apendicite experimental.The present study aims to evaluate the occurrence of the bacterial transmigration in induced ezxperimental appendicitis in rabbitis through complete oclusion of the vermiform appendix. 24 New Zealand white rabbits with a body weight ranging from 2500 to 3000 grams were used. They were divided into 2 groups. The animals from group I were submitted to a median

  5. Eficácia da associação de dexametasona à antibioticoterapia em pacientes pediátricos com meningite bacteriana Effectiveness of the association of dexamethasone with antibiotic therapy in pediatric patients with bacterial meningitis

    Directory of Open Access Journals (Sweden)

    Wanderley Marques Bernardo

    2012-06-01

    Full Text Available OBJETIVO: Avaliar a eficácia da associação de corticoide ao tratamento padrão da meningite bacteriana em pacientes pediátricos. MÉTODOS: Realizou-se revisão sistemática da literatura através da base de dados MEDLINE. Foram incluídos apenas ensaios clínicos controlados e randomizados que comparassem a dexametasona ao placebo no tratamento de pacientes pediátricos com meningite bacteriana. RESULTADOS: Oito artigos preencheram os critérios de inclusão e foram selecionados para análise. Não houve diferença nas taxas de mortalidade (p = 0,86 ou de incidências de sequelas neurológicas (p = 0,41 e audiológicas (p = 0,48 entre os grupos. CONCLUSÃO: Não existem benefícios na associação de corticoide ao tratamento da meningite bacteriana em pacientes pediátricos.OBJECTIVE: To evaluate the efficacy of the association of corticosteroids and the standard treatment of bacterial meningitis in pediatric patients. METHODS: A systematic review of the literature was conducted through the MEDLINE database. Only randomized controlled trials comparing dexamethasone with placebo in the treatment of pediatric patients with bacterial meningitis were included. RESULTS: Eight articles met the inclusion criteria and were selected for analysis. There were no difference in mortality (p = 0.86, and incidence of neurological (p = 0.41 and auditory (p = 0.48 sequelae between the groups. CONCLUSION: There are no benefits in associating corticosteroids with the standard treatment of bacterial meningitis in pediatric patients.

  6. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: Application in the control of Listeria monocytogenes in fresh Minas-type goat cheese

    OpenAIRE

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

    2015-01-01

    Listeria monocytogenes is a pathogen frequently found in dairy products. Its control in fresh cheeses is difficult, due to the psychrotrophic properties and salt tolerance. Bacteriocinogenic lactic acid bacteria (LAB) with proven in vitro antilisterial activity can be an innovative technological approach but their application needs to be evaluated by means of in situ tests. In this study, a novel bacteriocinogenic Lactococcus lactis strain ( Lc . lactis DF4Mi), isolated from raw goat milk, wa...

  7. Draft Genome Sequence of Lactococcus garvieae Strain PAQ102015-99, an Outbreak Strain Isolated from a Commercial Trout Farm in the Northwestern United States.

    Science.gov (United States)

    Nelson, Michael C; Varney, Jed S; Welch, Timothy J; Graf, Joerg

    2016-01-01

    We announce the draft genome assembly of Lactococcus garvieae strain PAQ102015-99, a recently isolated strain from an outbreak of lactococcosis at a commercial trout farm in the northwestern United States. The draft genome comprises 14 contigs totaling 2,068,357 bp with an N50 of 496,618 bp and average G+C content of 38%. PMID:27492003

  8. 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...

  9. Mucosal Delivery of Murine Interleukin-2 (IL-2) and IL-6 by Recombinant Strains of Lactococcus lactis Coexpressing Antigen and Cytokine

    OpenAIRE

    Steidler, Lothar; Robinson, K.; Chamberlain, L.; SCHOFIELD, KM; Remaut, Erik; LE PAGE, RWF; Wells, JM

    1998-01-01

    Lactococcus lactis is a nonpathogenic and noncolonizing bacterium which is being developed as a vaccine delivery vehicle for immunization by mucosal routes. To determine whether lactococci can also deliver cytokines to the immune system, we have constructed novel constitutive expression strains of L. lactis which accumulate a test antigen, tetanus toxin fragment C (TTFC), within the cytoplasmic compartment and also secrete either murine interleukin-2 (IL-2) or IL-6. When mice were immunized i...

  10. Aggregation of plaque disclosing agent in a dentifrice Incorporação de evidenciador de placa bacteriana a um dentifrício

    Directory of Open Access Journals (Sweden)

    Débora Dias da Silva

    2004-06-01

    Full Text Available Dental plaque removal is an important issue in health promotion. Toothbrushing is one of the main methods employed for such purpose, since it can prevent dental caries by means of the fluoride present in the dentifrice. Dentifrices might contain plaque disclosing agents and thus allow dental plaque observation. The aim of this study was to assess whether utilization of a plaque disclosing agent interfered with plaque removal among adolescents, as well as the difference between utilization of erythrosine tablets and dentifrices containing plaque disclosing agent. The sample was composed of 62 students from Piracicaba, SP, Brazil, aged 12 to 14 years old, divided into 3 groups: G1 or control group (toothbrushing without plaque disclosure; G2 (plaque disclosing with an erythrosine tablet and toothbrushing and G3 (toothbrushing with dentifrice containing plaque disclosing agent. After toothbrushing, disclosure of the remaining dental plaque was performed in all groups with a fuchsin tablet and measured through the Simplified Oral Health Assessment Index (OHI-S, in two stages with a 2-month interval between them. The analysis of variance (ANOVA showed that there was no difference in the OHI-S index between the groups (p>0.05, however the G3 displayed a higher proportion of students with plaque reduction (23% than G2 (21%, besides the smallest difference in the mean remaining dental plaque. There was no difference between groups; however, it was suggested that the dentifrice with plaque disclosing agent had positive results in relation to the erythrosine tablet, even though the small sample size may have interfered with the results, indicating the need of complementary studies.Na promoção de saúde, a remoção da placa bacteriana é um fator importante e um dos métodos que incentivam sua remoção, é a escovação dentária, podendo-se prevenir a cárie dental através do íon flúor dos dentifrícios. Estes podem conter evidenciadores

  11. Efeito de formulações cúpricas e cuprorgânicas na severidade da mancha-bacteriana e na população residente de Xanthomonas campestris pv. vesicatoria em pimentão

    OpenAIRE

    Aguiar Luiz Augusto de; Kimura Osamu; Castilho Alzimiro Marcelo C.; Castilho Kátia Simone C.; Ribeiro Raul de Lucena D.; Akiba Fujio; Carmo Margarida Goréte F. do

    2003-01-01

    Foram conduzidos dois experimentos de campo, em locais isolados entre si, objetivando avaliar o efeito de formulações cúpricas e cuprorgânicas na redução de populações de Xanthomonas campestris pv. vesicatoria presentes no filoplano do pimentão, bem como na redução da severidade dos sintomas da mancha-bacteriana. Numa das áreas experimentais, plantas da cultivar Cascadura Itaipu foram inoculadas com o isolado ENA-818, sensível ao cobre; na outra área, plantas da mesma cultivar foram inoculada...

  12. Peritonite bacteriana espontânea na cirrose hepática: prevalência, fatores preditivos e prognóstico Spontaneous bacterial peritonitis in hepatic cirrhosis: prevalence, predictive factors and prognosis

    OpenAIRE

    F.A.F. Figueiredo; H.S.M. Coelho; J.A.S. Soares

    1999-01-01

    OBJETIVO: Investigar prevalência, fatores preditivos e prognóstico dos episódios de Peritonite Bacteriana Espontânea (PBE) na cirrose hepática. METODOLOGIA: Estudamos, prospectivamente, 143 pacientes com cirrose hepática, ambulatoriais ou internados, que foram atendidos nos Serviços de Clínica Médica do HUCFF e de Gastroenterologia do HUPE no período de janeiro/95 a janeiro/96. Estes pacientes foram submetidos a questionário, exame físico, colheita de sangue e paracentese abdominal com colhei...

  13. Infecção bacteriana na leishmaniose cutânea: padrão bacteriano e sensibilidade a antibióticos Bacterial infection in cutaneous leishmaniasis: bacterial pattern and sensitivity to antibiotics

    OpenAIRE

    Eloísa da Graça do Rosário Gonçalves; Stelito Assis dos Reis Filho; Eurípedes Gomes de Oliveira; André Luiz Neves Pareira; Antonio Rafael da Silva; Jackson Maurício Lopes Costa

    2009-01-01

    Foi estudada a flora bacteriana em úlceras leishmanióticas, destacando-se o encontro das espécies aeróbicas Staphylococus aureus e Pseudomonas aeruginosa. O estudo da sensibilidade destas espécies a antibióticos mostrou sensibilidade à vancomicina, à amicacina e ao cloranfenicol em 100% dos isolados testados de Staphylococus aureus e à amicacina, à gentamicina e à tobramicina em 100% dos isolados testados de Pseudomonas aeruginosa. Estas espécies foram, em geral, resistentes às penicilinas e ...

  14. Short communication: Presence of Lactococcus and lactococcal exopolysaccharide operons on the leaves of Pinguicula vulgaris supports the traditional source of bacteria present in Scandinavian ropy fermented milk.

    Science.gov (United States)

    Porcellato, Davide; Tranvåg, Malena; Narvhus, Judith

    2016-09-01

    Some traditional Scandinavian fermented milk products have a pronounced ropy consistency due to the presence of exopolysaccharide-producing strains of Lactococcus lactis ssp. cremoris. Norwegian food folklore describes how leaves from the carnivorous plant Pinguicula vulgaris (common butterwort) may be added to milk to initiate the fermentation of the traditional fermented milk product tettemelk. However, scientific confirmation of the link between the plant and the milk product has not been previously published. In the present study, the microbiome on 20 samples of P. vulgaris leaves collected from 5 different rural geographical locations in Norway and from 4 samples of commercial tettemelk was analyzed using high-throughput sequencing methods. The leaf microbiota of P. vulgaris was dominated by Proteobacteria and Firmicutes and the genus Lactococcus was demonstrated in all leaf samples. In addition, DNA extracted from the leaf microbiome contained genes identical to those responsible for exopolysaccharide production in Lactococcus. These results confirm the traditional use of P. vulgaris as a source of bacteria for the Norwegian ropy fermented milk product tettemelk and indicate that P. vulgaris microbiomes can be a potential source of lactic acid bacteria with interesting dairy technological features. PMID:27423953

  15. Heterologous expression of Lactobacillus casei RecO improved the multiple-stress tolerance and lactic acid production in Lactococcus lactis NZ9000 during salt stress.

    Science.gov (United States)

    Wu, Chongde; Zhang, Juan; Du, Guocheng; Chen, Jian

    2013-09-01

    The aim of this study was to investigate the effect of nisin-inducible RecO expression on the stress tolerance of Lactococcus lactis NZ9000. RecO protein from Lactobacillus casei Zhang was introduced into Lactococcus lactis NZ9000 by using a nisin-inducible expression system. The recombinant strain (NZ-RecO) exhibited higher growth performances and survival rate compared with the control strain (NZ-Vector) under stress conditions. In addition, the NZ-RecO strain exhibited 1.37-, 1.41-, and 1.42-fold higher biomass, lactate production, lactate productivity, compared with the corresponding values for NZ-Vector during NaCl-stressed condition. Analysis of lactate dehydrogenase (LDH) activity showed that the production of RecO maintained the stability of LDH during salt stress. These results suggest that overproduction of RecO improved the multiple-stress tolerance and lactic acid production in Lactococcus lactis NZ9000 during salt stress. Results presented in this study may help to enhance the industrial utility of lactic acid bacteria. PMID:23796607

  16. Investigation of bacterial microbiota and risk factors in dogs with external ocular diseases from Bandeirantes, Paraná State, BrazilInvestigação da microbiota bacteriana e associações de risco em cães com afecções oculares externas atendidos em Bandeirantes, Paraná, Brasil

    Directory of Open Access Journals (Sweden)

    João Luis Garcia

    2012-02-01

    bilaterais, e 120 cães sem doenças oculares (grupo controle, foram atendidos entre 08/2008 a 07/2009 no Hospital Veterinário da Universidade Estadual do Norte do Paraná. As amostras coletadas do saco conjuntival inferior foram semeadas em ágar sangue e MacConkey e incubadas em aerobiose a 37ºC por até 120 horas. Após a identificação presuntiva, as espécies bacterianas foram identificadas pelos sistemas APISTAPH (bio- Merieux, Inc., API 20 STREP (bio-Merieux, Inc. e BACTRAY (Laborclin, ltda. e semeadas em agar Mueller-Hinton, para determinação da sensibilidade por meio da técnica de difusão de discos. Para as associações de risco, os proprietários dos 158 cães responderam um questionário com variáveis epidemiológicas. Das 63 amostras, houve crescimento de microrganismos em 46 (73,02%, com isolamento de um microrganismo em 42 amostras e de dois microrganismos em quatro. Bactérias Gram positivas corresponderam a 76% dos isolamentos, Gram negativas a 20% e fungos leveduriformes a 4%. Staphylococcus spp totalizaram 66% dos isolamentos, sendo S. aureus (24% e S. intermedius (24% as mais prevalentes. Exceto S. intermedius (91,67% e S. epidermidis (66,67%, as espécies bacterianas isoladas apresentaram resistência de 100% às sulfonamidas. Os S. aureus isolados apresentaram sensibilidade de 91,67% para cloranfenicol, tobramicina e amoxicilina/clavulanato, e o mesmo percentual de resistência para tetraciclina. Os S. intermedius apresentaram 100% de sensibilidade para amoxicilina/clavulanato e 91,67% para gentamicina e resistência de 75% para tetraciclina e ceftriaxona. As associações de risco para as doenças oculares externas foram recidivas clínicas (OR=59,50, 7,29

  17. Cervical necrotizing fasciitis due to bacterial tonsillitis Fasceite necrotizante cervical secundária a amigdalite bacteriana

    Directory of Open Access Journals (Sweden)

    Bruno Zilberstein

    2005-04-01

    Full Text Available Necrotizing fasciitis is a severe and potentially fatal soft tissue infection, but involvement of the head and neck is rare. We report on 4 cases of cervical necrotizing fasciitis arising from tonsillitis. One patient was diabetic and one had received steroids before disease development. One patient developed acute respiratory failure and died of septic shock. Three patients recovered, helped by early recognition, aggressive surgical intervention, appropriate broad-spectrum antibiotics, and supportive therapy. The common bacteria found in all abscess samples were Streptococcus sp., but mixed flora with anaerobic organisms was seen in all but 1 case. Tonsillitis and peritonsillar abscess must be suspected as a cause of cervical necrotizing fasciitis and a successful result can be achieved with immediate aggressive treatment.A fasceite necrotizante cervical é uma infecção grave de partes moles do pescoço. Trata-se de entidade rara, porém quando presente tem como principal origem um foco infeccioso odontogênico. São descritos 4 casos de fasceite necrotizante cervical a partir de tonsilites e abscesso peritonsilar, os quais, foram admitidos e tratados na unidade de terapia intensiva. Um dos pacientes era portador de Diabetes Melittus não insulino- dependente e outro paciente havia recebido corticoterapia antes do desenvolvimento da infecção. Em um dos casos ocorreu mediastinite, insuficiência respiratória e o paciente evolui para o óbito em decorrência de choque séptico. Durante o tratamento, 3 pacientes evoluíram satisfatoriamente devido ao diagnostico precoce, tratamento cirúrgico agressivo e utilização de antibiótico terapia de largo espectro. A bactéria mais comumente encontrada foi o Streptococcus sp, mas flora mista com germes anaeróbios foi encontrada em 3 dos casos descritos. CONCLUSÕES: Deve-se suspeitar de tonsilite e abscesso peritonsilar como causa de fasceite necrotizante cervical para que tratamento agressivo e

  18. Molecular analysis of the bacterial diversity in a specialized consortium for diesel oil degradation Análise molecular da diversidade bacteriana de um consórcio degradador de óleo diesel

    Directory of Open Access Journals (Sweden)

    Douglas Antonio Alvaredo Paixão

    2010-06-01

    desse produto contribuem significativamente para derrames acidentais, ocasionando sérios problemas ecológicos no solo e água, alterando assim toda a diversidade microbiológica do ambiente. A estratégia de clonagem e sequenciamento do gene 16S rRNA é uma das técnicas moleculares que permitem estimar e comparar a diversidade microbiana de diferentes amostras ambientais, sejam elas impactadas ou não. O objetivo deste trabalho foi estimar a diversidade de microrganismos pertencentes ao domínio Bacteria em um consórcio degradador de óleo diesel por meio de sequenciamento parcial do gene 16S rRNA. Após extração do DNA metagenômico, o material foi amplificado por reação de PCR com oligonucleotídeos iniciadores específicos para o gene 16S rRNA. Os produtos da reação de PCR foram clonados em vetor pGEM T Easy (Promega e transformados em células competentes de Escherichia coli. O sequenciamento parcial dos clones foi feito com oligonucleotídeos universais do vetor. A biblioteca obtida gerou 431 clones. Todos os clones mostraram similaridade com o filo Proteobacteria, onde as Gammaproteobacteria compreenderam o grupo de maior representatividade, com 49,8 % dos clones, seguida das Alphaproteobacteira, com 44,8 %, e das Betaproteobacteria, com 5,4 %. O gênero Pseudomonas destacou-se como representante com maior frequência de clones na biblioteca, seguido pelos gêneros Parvibaculum e Sphingobium. Após o sequenciamento parcial do gene 16S rRNA, a diversidade bacteriana do consórcio foi estimada utilizando-se o software DOTUR. Essas sequências, quando comparadas com as do banco do National Center for Biotechnology Information (NCBI, mostraram grande correlação entre os dados gerados pelo software utilizado e aqueles depositados no NCBI.

  19. Contaminação bacteriana e fúngica de canudos de refrigerantes e seus recipientes em lanchonetes de município do interior de São Paulo Fungal and bacterial contamination of drinking straws and their containers in snack bars in a municipality of São Paulo state, Brazil

    Directory of Open Access Journals (Sweden)

    Francisco Rafael Martins Soto

    2009-12-01

    Full Text Available OBJETIVO: Avaliar o nível de contaminação bacteriana e fúngica de canudos de refrigerantes e seus recipientes em 30 lanchonetes do Município de Ibiúna (SP, correlacionando com as condições de higiene, processos e métodos de desinfecção destes estabelecimentos. MÉTODOS: Foram colhidas três amostras por estabelecimento nas embalagens fechadas, em recipientes e swab em toda a superfície de contato. Foi aplicado um questionário a fim de avaliar: a empresa fornecedora dos canudos, higienização, freqüência e desinfecção, e foram efetuadas inspeções sanitárias nos estabelecimentos. Para as análises microbiológicas foi utilizada a técnica de lavagem superficial e semeadura em meios, para contagem de bactérias mesófilas. As amostras turvas foram semeadas em meios de cultura para: Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, Enterococcus, coliformes totais e/ou termotolerantes. RESULTADOS: Dentre os microorganismos isolados nas amostras dos canudos nos recipientes foi detectado Bacillus cereus em 36,6%, Enterococo spp. em 3,3%. O Bacillus cereus foi isolado em 46,6% nos swabs dos recipientes, e em 13,3%, Enterococos. Na análise de associação do nível de contaminação microbiana de canudos de refrigerantes e seus recipientes com as condições de higiene, os processos de higienização e a desinfecção dos estabelecimentos, não foi identifica significância estatística (p>0,05. CONCLUSÃO: O Bacillus cereus foi o microorganismo que prevaleceu nas embalagens íntegras dos canudos, nos seus recipientes e no swab das superfícies. Não foi comprovada a associação de fatores de risco de contaminação bacteriana e fúngica.OBJECTIVE: The objective of this study was to evaluate the fungal and bacterial contamination level of drinking straws and their containers of thirty snack bars at the municipality of Ibiuna (SP, Brazil and to correlate these data with conditions of hygiene and the processes and

  20. Sociedad por Acciones Simplificada

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Arcila Salazar

    2009-06-01

    Full Text Available En Colombia, aspectos como la responsabilidad limitada; supresión de la llamada doctrina de ultra vires; duración ilimitada; eliminación de la regla, una acción, un voto; remedios al abuso de los derechos; posibilidad de eliminar prohibiciones a los administradores, libertad de establecer restricciones para la transferencia de acciones y la simplificación de los procedimientos de fusión; son inviables bajo nuestra legislación. Sin embargo, la Ley 1258 de 2008, ha incorporado al derecho societario colombiano un nuevo tipo societario híbrido, llamado “Sociedad por Acciones Simplificada”. Esta forma societaria híbrida se basa en un principio básico: garantizar amplia libertad a los empresarios en la estructuración de sus relaciones a través de disposiciones contractuales. La S.A.S. provee a los empresarios significativa flexibilidad contractual, a la vez que preserva beneficios como la limitación de la responsabilidad.

  1. Sociedad por Acciones Simplificada

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Arcila Salazar

    2009-07-01

    Full Text Available En Colombia, aspectos como la responsabilidad limitada; supresión de la llamada doctrina de ultra vires; duración ilimitada; eliminación de la regla, una acción, un voto; remedios al abuso de los derechos; posibilidad de eliminar prohibiciones a los administradores, libertad de establecer restricciones para la transferencia de acciones y la simplificación de los procedimientos de fusión; son inviables bajo nuestra legislación. Sin embargo, la Ley 1258 de 2008, ha incorporado al derecho societario colombiano un nuevo tipo societario híbrido, llamado “Sociedad por Acciones Simplificada”. Esta forma societaria híbrida se basa en un principio básico: garantizar amplia libertad a los empresarios en la estructuración de sus relaciones a través de disposiciones contractuales. La S.A.S. provee a los empresarios significativa flexibilidad contractual, a la vez que preserva beneficios como la limitación de la responsabilidad.

  2. Efecto del pH, cepa bacteriana y tipo de muestra, en la detección microbiológica, de ácido oxolínico y oxitetraciclina en peces Influence of pH, microbial strain and sample type, on the microbiological detection of oxolinic acid and oxitetraciclyne in fish

    Directory of Open Access Journals (Sweden)

    ERIKA GESCHE

    2001-01-01

    Full Text Available Junto al desarrollo de la salmonicultura, surge la necesidad de aplicación de antimicrobianos para el control de enfermedades de los peces, aumentando el riesgo de la presencia de residuos en el producto destinado al consumo. Con la finalidad de aportar antecedentes a la detección microbiológica de residuos de ácido oxolínico y oxitetraciclina en peces, se trataron, 75 peces de la especie Salmo salar con cada uno de los antibióticos. Para ello se escogieron peces con un peso promedio de 2,7 Kg, y durante 10 días se les administró por vía oral la dosis indicada por el fabricante para ambos antibacterianos. Finalizado el período de tratamiento, se tomaron muestras de músculo y suero de 5 peces en los días 1 a 5 y 10, 15, 20 y 30 post tratamiento. Las muestras fueron conservadas en congelación para luego ser analizadas por el método de detección del antibiótico por inhibición bacteriana, utilizando Bacillus subtilis BGA y E. coli ATCC 11303 como cepas sensibles, incluidas en un medio de cultivo nutritivo a pH 6,0 y 8,0 respectivamente. Muestras de suero y de músculo de cada pez se colocaron en duplicado en cada una de las 4 placas de Petri con los diferentes substratos de cultivo. Después de la incubación de las placas a 35 ºC por 24 h se midió el halo de inhibición bacteriana (en mm provocado por la difusión del residuo. Los resultados demuestran que el ácido oxolínico y la oxitetraciclina se detectan mejor en el substrato a pH 6,0, y que la cepa Bacillus subtilis BGA, es más sensible que E.coli ATCC 11303, a la detección de ambos antibacterianos. Las muestras de suero provocaron halos de inhibición de mayor tamaño que las de músculo del mismo pez y demostraron una mayor persistencia del residuo a través del tiempo de depleción de los fármacosSimultaneously with the development of the salmoniculture, comes forth the need to use antimicrobial drugs to control fish disease thus, increasing the risk of residues in

  3. Atividades de quitinase e beta-1,3-glucanase após eliciação das defesas do tomateiro contra a mancha-bacteriana Chitinase and beta-1,3-glucanase activities after the elicitation of tomato defenses against bacterial spot

    Directory of Open Access Journals (Sweden)

    Fábio Rossi Cavalcanti

    2006-12-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência de eliciadores biológicos e químicos sobre as atividades de duas proteínas relacionadas à patogênese (PR, quitinase e beta-1,3-glucanase, em folhas de tomateiro, e avaliar o potencial desses eliciadores na redução do progresso da mancha-foliar causada por Xanthomonas campestris pv. vesicatoria. Plantas de tomateiro da cultivar Santa Cruz Kada foram pulverizadas com: acibenzolar-S-metil (ASM; 0,2 g L-1; formulação biológica proveniente de biomassa cítrica, denominada Ecolife (5 mL L-1; suspensão de quitosana (MCp; 200 g L-1, proveniente de micélio de Crinipellis perniciosa; extrato aquoso de ramos de lobeira (Solanum lycocarpum infectados por C. perniciosa (VLA; 300 g L-1. As plantas foram desafiadas com um isolado virulento da bactéria, quatro dias depois das pulverizações. Plantas pulverizadas com extratos biológicos mostraram redução da mancha-bacteriana. ASM proporcionou 49,3% de proteção, e foi igual à MCp e Ecolife e superior ao VLA. Este último não diferiu significativamente de MCp e Ecolife. Observou-se maior atividade das duas enzimas nas plantas tratadas, principalmente nas primeiras horas após as pulverizações.The objective of this work was to assess the influence of foliar application of resistance inducers and the activation of plant pathogenesis-related (PR proteins, chitinases and beta-1,3-glucanases, against Xanthomonas campestris pv. vesicatoria, and evaluate the potential of these elicitors on the reduction of bacterial leaf spot. Tomato plants of the cultivar Santa Cruz Kada were sprayed with: acibenzolar-S-methyl (0.2 g L-1 ASM; Ecolife, a biological formulation based on citric biomass (5 mL L-1; chitosan suspension from Crinipellis perniciosa mycelium (MCp; 200 g L-1; an aqueous extract from branches of lobeira (Solanum lycocarpum infected with C. perniciosa (VLA; 300 g L-1. Plants were challenged with a virulent bacterial strain four days after

  4. The Plasmid Complement of the Cheese Isolate Lactococcus garvieae IPLA 31405 Revealed Adaptation to the Dairy Environment

    Science.gov (United States)

    Flórez, Ana Belén; Mayo, Baltasar

    2015-01-01

    Lactococcus garvieae is a lactic acid bacterium found in raw-milk dairy products as well as a range of aquatic and terrestrial environments. The plasmids in L. garvieae have received little attention compared to those of dairy Lactococcus lactis, in which the genes carried by these extrachromosomal elements are considered of adaptive value. The present work reports the sequencing and analysis of the plasmid complement of L. garvieae IPLA 31405, a strain isolated from a traditional, Spanish, starter-free cheese made from raw-milk. It consists of pLG9 and pLG42, of 9,124 and 42,240 nucleotides, respectively. Based on sequence and structural homology in the putative origin of replication (ori) region, pLG9 and pLG42 are predicted to replicate via a theta mechanism. Real-time, quantitative PCR showed the number of copies per chromosome equivalent of pLG9 and pLG42 to be around two and five, respectively. Sequence analysis identified eight complete open reading frames (orfs) in pLG9 and 36 in pLG42; these were organized into functional modules or cassettes containing different numbers of genes. These modules were flanked by complete or interrupted insertion sequence (IS)-like elements. Among the modules of pLG42 was a gene cluster encoding specific components of a phosphoenolpyruvate-phosphotransferase (PEP-PTS) system, including a phospho-β-galacosidase. The cluster showed a complete nucleotide identity respect to that in plasmids of L. lactis. Loss of pLG42 showed this to be involved in lactose assimilation. In the same plasmid, an operon encoding a type I restriction/modification (R/M) system was also identified. The specificity of this R/M system might be broadened by different R/M specificity subunits detected in pLG9 and in the bacterial chromosome. However, challenges of L. garvieae IPLA 31405 against L. lactis phages proved that the R/M system was not involved in phage resistance. Together, these results support the hypothesis that, as in L. lactis, pLG42

  5. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    Science.gov (United States)

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy.

  6. Construction of a new shuttle vector for DNA delivery into mammalian cells using non-invasive Lactococcus lactis.

    Science.gov (United States)

    Yagnik, Bhrugu; Padh, Harish; Desai, Priti

    2016-04-01

    Use of food grade Lactococcus lactis (L. lactis) is fast emerging as a safe alternative for delivery of DNA vaccine. To attain efficient DNA delivery, L. lactis, a non-invasive bacterium is converted to invasive strain either by expressing proteins like Internalin A (InlA) or Fibronectin binding protein A (FnBPA) or through chemical treatments. However the safety status of invasive L. lactis is questionable. In the present report, we have shown that non-invasive L. lactis efficiently delivered the newly constructed reporter plasmid pPERDBY to mammalian cells without any chemical enhancers. The salient features of the vector are; I) Ability to replicate in two different hosts; Escherichia coli (E. coli) and Lactic Acid Bacteria (LAB), II) One of the smallest reporter plasmid for DNA vaccine, III) Enhanced Green Fluorescence Protein (EGFP) linked to Multiple Cloning Site (MCS), IV) Immunostimulatory CpG motifs functioning as an adjuvant. Expression of EGFP in pPERDBY transfected CHO-K1 and Caco-2 cells demonstrates its functionality. Non-invasive r-L. lactis was found efficient in delivering pPERDBY to Caco-2 cells. The in vitro data presented in this article supports the hypothesis that in the absence of invasive proteins or relevant chemical treatment, L. lactis was found efficient in delivering DNA to mammalian cells. PMID:26655884

  7. Antimicrobial activity of the Nisin Z producer Lactococcus lactis subsp. lactis Lc08 against Listeria monocytogenes in skim milk

    Directory of Open Access Journals (Sweden)

    L.M. Perin

    2013-10-01

    Full Text Available The presented study aimed to verify the effect of different pH values, enzyme solutions and heat treatments on the antimicrobial activity of the bacteriocinogenic strain Lactococcus lactis subsp. lactis Lc08 and to test their antimicrobial activity against Listeria monocytogenes in reconstituted skim milk at refrigeration temperatures. This strain was previously described as a nisin Z producer and capable of inhibiting L. monocytogenes growth in in vitro tests. The antimicrobial activity of the bacteriocin cell-free supernatant of Lc08 was sensitive to enzyme treatments (except papain. The pH values and heating (65ºC for 30min, 75ºC for 15s had no apparent effect on the antimicrobial activity of the bacteriocin produced by Lc08. Only treatment at autoclave conditions result in loss of their antimicrobial activity. Lc08 presented antimicrobial activity against L. monocytogenes in the milk system after 12h at 25ºC. No effect was found at 7ºC. The results show the application viability of the Lc08 in food systems as a biopreservative against L. monocytogenes.

  8. A distinct single-stranded DNA-binding protein encoded by the Lactococcus lactis bacteriophage bIL67.

    Science.gov (United States)

    Szczepanska, Agnieszka K; Bidnenko, Elena; Płochocka, Danuta; McGovern, Stephen; Ehrlich, S Dusko; Bardowski, Jacek; Polard, Patrice; Chopin, Marie-Christine

    2007-06-20

    Single-stranded binding proteins (SSBs) are found to participate in various processes of DNA metabolism in all known organisms. We describe here a SSB protein encoded by the Lactococcus lactis phage bIL67 orf14 gene. It is the first noted attempt at characterizing a SSB protein from a lactococcal phage. The purified Orf14(bIL67) binds unspecifically to ssDNA with the same high affinity as the canonical Bacillus subtilis SSB. Electrophoretic mobility-shift assays performed with mutagenized Orf14(bIL67) protein derivatives suggest that ssDNA-binding occurs via a putative OB-fold structure predicted by three-dimensional modeling. The native Orf14(bIL67) forms homotetramers as determined by gel filtration studies. These results allow distinguishing the first lactococcal phage protein with single-strand binding affinity, which defines a novel cluster of phage SSBs proteins. The possible role of Orf14(bIL67) in phage multiplication cycle is also discussed.

  9. Oral Vaccination with the Porcine Rotavirus VP4 Outer Capsid Protein Expressed by Lactococcus lactis Induces Specific Antibody Production

    Directory of Open Access Journals (Sweden)

    Yi-jing Li

    2010-01-01

    Full Text Available The objective of this study to design a delivery system resistant to the gastrointestinal environment for oral vaccine against porcine rotavirus. Lactococcus lactis NZ9000 was transformed with segments of vP4 of the porcine rotavirus inserted into the pNZ8112 surface-expression vector, and a recombinant L. lactis expressing VP4 protein was constructed. An approximately 27 kDa VP4 protein was confirmed by SDS-PAGE , Western blot and immunostaining analysis. BALB/c mice were immunized orally with VP4-expression recombinant L. lactis and cellular, mucosal and systemic humoral immune responses were examined. Specific anti-VP4 secretory IgA and IgG were found in feces, ophthalmic and vaginal washes and in serum. The induced antibodies demonstrated neutralizing effects on porcine rotavirus infection on MA104 cells. Our findings suggest that oral immunization with VP4-expressing L. lactis induced both specific local and systemic humoral and cellular immune responses in mice.

  10. A food-grade fimbrial adhesin FaeG expression system in Lactococcus lactis and Lactobacillus casei.

    Science.gov (United States)

    Lu, W W; Wang, T; Wang, Y; Xin, M; Kong, J

    2016-03-01

    Enterotoxigenic Escherichia coli (ETEC) infection is the major cause of diarrhea in neonatal piglets. The fimbriae as colonizing factor in the pathogenesis of ETEC constitute a primary target for vaccination against ETEC. Lactic acid bacteria (LAB) are attractive tools to deliver antigens at the mucosal level. With the safety of genetically modified LAB in mind, a food-grade secretion vector (pALRc or pALRb) was constructed with DNA entirely from LAB, including the replicon, promoter, signal peptide, and selection marker alanine racemase gene (alr). To evaluate the feasibility of the system, the nuclease gene (nuc) from Staphylococcus aureus was used as a reporter to be expressed in both Lactococcus lactis and Lactobacillus casei. Subsequently, the extracellular secretion of the fimbrial adhesin FaeG of ETEC was confirmed by Western blot analysis. These results showed that this food-grade expression system has potential as the delivery vehicle for the safe use of genetically modified LAB for the development of vaccines against ETEC infection.

  11. A food-grade fimbrial adhesin FaeG expression system in Lactococcus lactis and Lactobacillus casei.

    Science.gov (United States)

    Lu, W W; Wang, T; Wang, Y; Xin, M; Kong, J

    2016-03-01

    Enterotoxigenic Escherichia coli (ETEC) infection is the major cause of diarrhea in neonatal piglets. The fimbriae as colonizing factor in the pathogenesis of ETEC constitute a primary target for vaccination against ETEC. Lactic acid bacteria (LAB) are attractive tools to deliver antigens at the mucosal level. With the safety of genetically modified LAB in mind, a food-grade secretion vector (pALRc or pALRb) was constructed with DNA entirely from LAB, including the replicon, promoter, signal peptide, and selection marker alanine racemase gene (alr). To evaluate the feasibility of the system, the nuclease gene (nuc) from Staphylococcus aureus was used as a reporter to be expressed in both Lactococcus lactis and Lactobacillus casei. Subsequently, the extracellular secretion of the fimbrial adhesin FaeG of ETEC was confirmed by Western blot analysis. These results showed that this food-grade expression system has potential as the delivery vehicle for the safe use of genetically modified LAB for the development of vaccines against ETEC infection. PMID:26825016

  12. Preliminary X-ray crystallographic analysis of the d-xylulose 5-phosphate phosphoketolase from Lactococcus lactis

    International Nuclear Information System (INIS)

    The expression, purification, preliminary crystallization and crystallographic analysis of phosphoketolase from L. lactis ssp. lactis (strain IL 1403) are reported. Phosphoketolases are thiamine diphosphate-dependent enzymes which play a central role in the pentose-phosphate pathway of heterofermentative lactic acid bacteria. They belong to the family of aldehyde-lyases and in the presence of phosphate ion cleave the carbon–carbon bond of the specific substrate d-xylulose 5-phosphate (or d-fructose 6-phosphate) to give acetyl phosphate and d-glyceraldehyde 3-phosphate (or d-erythrose 4-phosphate). Structural information about phosphoketolases is particularly important in order to fully understand their mechanism as well as the steric course of phosphoketolase-catalyzed reactions. Here, the purification, preliminary crystallization and crystallographic characterization of d-xylulose 5-phosphate phosphoketolase from Lactococcus lactis are reported. The presence of thiamine diphosphate during purification was essential for the enzymatic activity of the purified protein. The crystals belonged to the monoclinic space group P21. Diffraction data were obtained to a resolution of 2.2 Å

  13. Expression of Helicobacter pylori hspA Gene in Lactococcus lactis NICE System and Experimental Study on Its Immunoreactivity

    Directory of Open Access Journals (Sweden)

    Xiao-Juan Zhang

    2015-01-01

    Full Text Available 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 adopted, respectively, to detect the HspA expressed by recombinant L. lactis and its immunoreactivity. Results. There was no effect observed from the growth curve after exogenous gene hspA was cloned into L. lactis NZ3900; different concentrations of Nisin did not affect the growth of NZ3900 and NZ3900/pNZ8110, while different concentrations of Nisin inhibited the growth of NZ3900/pNZ8110-hspA except 10 ng/mL Nisin. No HspA strip was observed from SDS-PAGE. Western blot analysis showed that HspA expressed by recombinant bacteria had favorable immunoreactivity. Conclusion. The growth of recombinant L. lactis was suppressed even though a small amount of HspA had been induced to express. Therefore recombinant L. lactis only express HspA which was not suitable to be oral vaccine against Helicobacter pylori.

  14. Nisin production of Lactococcus lactis N8 with hemin-stimulated cell respiration in fed-batch fermentation system.

    Science.gov (United States)

    Kördikanlıoğlu, Burcu; Şimşek, Ömer; Saris, Per E J

    2015-01-01

    In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed-batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed-batch fermentation system with high fidelity (R(2) 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L(-1) h(-1) , 3 μg mL(-1) and 40%, respectively. While 1711 IU mL(-1) nisin was produced by L. lactis N8 in control fed-batch fermentation, 5410 IU mL(-1) nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed-batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed-batch fermentation.

  15. Effect of oral Lactococcus lactis containing endostatin on 1,2-dimethvlhvdrazine-induced colon tumor in rats

    Institute of Scientific and Technical Information of China (English)

    Wei Li; Chong-Bi Li

    2005-01-01

    AIM: To investigate the effects of oral Lactococcus lactis (Llactis) containing endostatin on 1, 2-dimethylhydrazine (DMH)-induced rat colorectal cancer.METHODS: Recombinant endostatin was produced by the expression of L lactis NZ9000. Sixty male Wistar rats were injected with DMH (40 mg/kg body weight) subcutaneously once a week for 10 wk to induce colorectal cancer. The rats were gavaged with 1 mL of endostatin at a dose of 1×108/d and fed with the basal diet. The animals were killed after 22 wk for histopathological examination. The total time of experimental observation was 58 wk.RESULTS: Rat endostatin protein was expressed in L lactis. Recombinant endostatin exhibited a significant effect on colorectal cancer (P<0.05). Furthermore, the mean survival time of the rats treated with endostatin was longer than that of the animals treated with DMH.There was no statistically significant difference between the rats treated with endostatin and those treated with DMH. The results showed that endostatin could not result in complete cure.CONCLUSION: Oral endostatin exerts an influence on the progression of chemically induced colon tumors.

  16. Biogenic amine production by Lactococcus lactis subsp. cremoris strains in the model system of Dutch-type cheese.

    Science.gov (United States)

    Flasarová, Radka; Pachlová, Vendula; Buňková, Leona; Menšíková, Anna; Georgová, Nikola; Dráb, Vladimír; Buňka, František

    2016-03-01

    The aim of this study was to compare the biogenic amine production of two starter strains of Lactococcus lactis subsp. cremoris (strains from the Culture Collection of Dairy Microorganisms - CCDM 824 and CCDM 946) with decarboxylase positive activity in a model system of Dutch-type cheese during a 90-day ripening period at 10°C. During ripening, biogenic amine and free amino acid content, microbiological characteristics and proximate chemical properties were observed. By the end of the ripening period, the putrescine content in both samples with the addition of the biogenic amine producing strain almost evened out and the concentration of putrescine was >800mg/kg. The amount of tyramine in the cheeses with the addition of the strain of CCDM 824 approached the limit of 400mg/kg by the end of ripening. In the cheeses with the addition of the strain of CCDM 946 it even exceeded 500mg/kg. In the control samples, the amount of biogenic amines was insignificant. PMID:26471528

  17. Influence of cofermentation by amylolytic Lactobacillus plantarum and Lactococcus lactis strains on the fermentation process and rheology of sorghum porridge.

    Science.gov (United States)

    Mukisa, Ivan M; Byaruhanga, Yusuf B; Muyanja, Charles M B K; Aijuka, Matthew; Schüller, Reidar B; Sahlstrøm, Stefan; Langsrud, Thor; Narvhus, Judith A

    2012-08-01

    Amylolytic lactic acid bacteria (ALAB) can potentially replace malt in reducing the viscosity of starchy porridges. However, the drawback of using ALAB is their low and delayed amylolytic activity. This necessitates searching for efficient ALAB and strategies to improve their amylolytic activity. Two ALAB, Lactobacillus plantarum MNC 21 and Lactococcus lactis MNC 24, isolated from Obushera, were used to ferment starches in MRS broth: sorghum, millet, sweet potato, and commercial soluble starch. The amylolytic activity of MNC 21 was comparable to that of the ALAB collection strain Lb. plantarum A6, while that of MNC 24 was extremely low. MNC 21, MNC 24, and their coculture were compared to A6 and sorghum malt for ability to ferment and reduce the viscosity of sorghum porridge (11.6% dry matter). ALAB and the coculture lowered the pH from 6.2 to porridge than the monocultures. The coculture initiated changes in the rheological parameters storage modulus (G'), loss modulus (G″), phase angle (δ), and complex viscosity (η*) earlier than its constituent monocultures. The shear viscosity of sorghum porridge was reduced significantly (P < 0.05) from 1950 cP to 110 cP (malt), 281 cP (coculture), 382 cP (MNC 21), 713 cP (MNC 24), and 722 cP (A6). Coculturing strong ALAB with weak ALAB or non-ALAB can be exploited for preparation of nutrient-dense weaning foods and increasing lactic acid yield from starchy materials.

  18. Lacticin LC14, a new bacteriocin produced by Lactococcus lactis BMG6.14: isolation, purification and partial characterization.

    Science.gov (United States)

    Lasta, Samar; Ouzari, Hadda; Andreotti, Nicolas; Fajloun, Ziad; Mansuelle, Pascal; Boudabous, Abdellatif; Sampieri, Francois; Sabatier, Jean Marc

    2012-08-01

    A new bacteriocin, lacticin LC14, produced by Lactococcus lactis BMG6.14, was isolated and characterized. It was purified to homogeneity from overnight broth culture by ammonium sulfate precipitation, Sep-Pak chromatography, and two steps of reversed-phase HPLC. Lacticin LC14 showed bactericidal-type antimicrobial activity against several lactic acid bacteria and pathogenic strains including Listeria monocytogenes. It was inactivated by proteinase K and pronase E, but was resistant to papain, lysozyme, lipase and catalase. Lacticin LC14 was heat resistant, stable over a wide range of pH (2-10) and after treatment by solvents and detergents. Its N-terminal end was found unreactive towards Edman sequencing. Based on MALDI-TOF mass spectrometry, its molecular mass was 3333.7 Da. LC14 amino acid composition revealed a high proportion of hydrophobic residues, but no modified ones. LC14 may be able to challenge other well known other bacteriocins in probiotic and therapeutic applications.

  19. Induction of a stress response in Lactococcus lactis is associated with a resistance to ribosomally active antibiotics.

    Science.gov (United States)

    Dorrian, James M; Briggs, Deborah A; Ridley, Michael L; Layfield, Robert; Kerr, Ian D

    2011-11-01

    The acquisition of multidrug resistance in bacteria underlies the failure of antimicrobial therapy, and the emergence of pathogens that are resistant to almost the entire armoury of antibiotics. Among the proteins that can mediate or contribute to the drug-resistance profile in Gram-positive bacteria is a subset of ATP-binding cassette proteins that are comprised of a tandem-repeated nucleotide-binding domain. In this study, we expressed one of these NBD(2) proteins, LmrC, in an antibiotic-sensitive Gram-positive host strain (Lactococcus lactis) and demonstrated the acquisition of resistance to ribosomally active antibiotics. Mutation of key catalytic residues suggested that the resistance profile was the result of a cellular response, rather than being a function of the NBD(2) protein itself. This observation was confirmed by 2D SDS/PAGE, which demonstrated that the expression of the NBD(2) protein induced a stress response in L. lactis. A model combining this stress response induction and the acquisition of antibiotic resistance is proposed. PMID:21848804

  20. Biogenic amine production by Lactococcus lactis subsp. cremoris strains in the model system of Dutch-type cheese.

    Science.gov (United States)

    Flasarová, Radka; Pachlová, Vendula; Buňková, Leona; Menšíková, Anna; Georgová, Nikola; Dráb, Vladimír; Buňka, František

    2016-03-01

    The aim of this study was to compare the biogenic amine production of two starter strains of Lactococcus lactis subsp. cremoris (strains from the Culture Collection of Dairy Microorganisms - CCDM 824 and CCDM 946) with decarboxylase positive activity in a model system of Dutch-type cheese during a 90-day ripening period at 10°C. During ripening, biogenic amine and free amino acid content, microbiological characteristics and proximate chemical properties were observed. By the end of the ripening period, the putrescine content in both samples with the addition of the biogenic amine producing strain almost evened out and the concentration of putrescine was >800mg/kg. The amount of tyramine in the cheeses with the addition of the strain of CCDM 824 approached the limit of 400mg/kg by the end of ripening. In the cheeses with the addition of the strain of CCDM 946 it even exceeded 500mg/kg. In the control samples, the amount of biogenic amines was insignificant.

  1. Interaction of Saccharomyces cerevisiae and Lactococcus lactis in the fermentation and quality of artisanal cachaça

    Directory of Open Access Journals (Sweden)

    Fernanda Paula Carvalho

    2014-11-01

    Full Text Available Lactococcus lactis and Saccharomyces cerevisiae in co-culture were evaluated during sugar cane fermentantion for cachaça production. The inocula containing L. lactis UFLA CA 312 and S. cerevisiae UFLA CA 11 were used in the population of approximately 105 CFU mL-1 and 108 CFU mL-1,  respectively. The sugar cane medium plus 1% of yeast extract (SCM was efficient for growth of L. lactis UFLA CA 312 and S. cerevisiae UFLA CA 11 (letter b -Tukey test. In flasks and vats fermentation the growth of UFLA CA 11 was not negatively influenced by L. lactis UFLA CA 312. However, after 19 h of fermentation, bacterial population showed a slight decrease. Considering parameters higher alcohols and aldehydes, cachaça produced by pure culture of S. cerevisiae was similar to cachaça produced by mixed culture. Cachaça produced by mixed culture showed high values of volatile acidity (letter b -Scott-Knott test being characterized by this parameters in the principal component analysis. High percentage of acceptance (81.10% for the attribute aroma was observed in samples from cachaça produced by mixed culture.

  2. Structure-guided engineering of Lactococcus lactis alcohol dehydrogenase LlAdhA for improved conversion of isobutyraldehyde to isobutanol

    KAUST Repository

    Liu, Xiang

    2013-03-01

    We have determined the X-ray crystal structures of the NADH-dependent alcohol dehydrogenase LlAdhA from Lactococcus lactis and its laboratory-evolved variant LlAdhA(RE1) at 1.9Å and 2.5Å resolution, respectively. LlAdhA(RE1), which contains three amino acid mutations (Y50F, I212T, and L264V), was engineered to increase the microbial production of isobutanol (2-methylpropan-1-ol) from isobutyraldehyde (2-methylpropanal). Structural comparison of LlAdhA and LlAdhA(RE1) indicates that the enhanced activity on isobutyraldehyde stems from increases in the protein\\'s active site size, hydrophobicity, and substrate access. Further structure-guided mutagenesis generated a quadruple mutant (Y50F/N110S/I212T/L264V), whose KM for isobutyraldehyde is ∼17-fold lower and catalytic efficiency (kcat/KM) is ∼160-fold higher than wild-type LlAdhA. Combining detailed structural information and directed evolution, we have achieved significant improvements in non-native alcohol dehydrogenase activity that will facilitate the production of next-generation fuels such as isobutanol from renewable resources.

  3. L+-lactic acid production from starch by a novel amylolytic Lactococcus lactis subsp. lactis B84.

    Science.gov (United States)

    Petrov, Kaloyan; Urshev, Zoltan; Petrova, Penka

    2008-06-01

    A new Lactococcus lactis subsp. lactis B84, capable of utilizing starch as a sole carbon source and producing L(+)-lactate, was isolated from spontaneously fermented rye sourdough. Aiming at maximum lactic acid productivity, the components of the media and the cultivation conditions were varied. In MRS-starch medium (with absence of yeast and meat extracts), at 33 degrees C, agitation 200 rpm and pH 6.0 for 6 days complete starch hydrolysis occurred and 5.5 gl(-1) lactic acid were produced from 18 gl(-1) starch. The identification of strain B84 was based on genetic criteria. Amplified ribosomal DNA restriction analysis (ARDRA), PCR with species-specific primers and sequencing of the 16S rDNA proved its species affiliation. Four genes for enzymes, involved in starch degradation were detected in B84 genome: amyL, amyY, glgP and apu, coding cytoplasmic and extracellular alpha-amylases, glycogen phosphorylase and amylopullulanase, respectively. Reverse transcription PCR experiments showed that both genes, encoding alpha-amylases (amyL and amyY) were expressed into mRNAs, whereas apu and glgP were not. Amylase activity assay was performed at different pH and temperatures. The cell-bond amylase proved to be the key enzyme, involved in the starch hydrolysis with maximum activity at 45 degrees C and pH 5.4.

  4. Lytic infection of Lactococcus lactis by bacteriophages Tuc2009 and c2 triggers alternative transcriptional host responses.

    Science.gov (United States)

    Ainsworth, Stuart; Zomer, Aldert; Mahony, Jennifer; van Sinderen, Douwe

    2013-08-01

    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 throughout lytic infection. Whole-genome microarrays performed at various time points postinfection demonstrated a rather modest impact on host transcription. The majority of changes in the host transcriptome occur during late infection stages; few changes in host gene transcription occur during the immediate and early infection stages. Alterations in the L. lactis UC509.9 transcriptome during lytic infection appear to be phage specific, with relatively few differentially transcribed genes shared between cells infected with Tuc2009 and those infected with c2. Despite the apparent lack of a coordinated general phage response, three themes common to both infections were noted: alternative transcription of genes involved in catabolic flux and energy production, differential transcription of genes involved in cell wall modification, and differential transcription of genes involved in the conversion of ribonucleotides to deoxyribonucleotides. The transcriptional profiles of both bacteriophages during lytic infection generally correlated with the findings of previous studies and allowed the confirmation of previously predicted promoter sequences. In addition, the host transcriptional response to lysogenization with Tuc2009 was monitored along with tiling array analysis of Tuc2009 in the lysogenic state. Analysis identified 44 host genes with altered transcription during lysogeny, 36 of which displayed levels of transcription significantly reduced from those for uninfected cells.

  5. Expression of PprI from Deinococcus radiodurans Improves Lactic Acid Production and Stress Tolerance in Lactococcus lactis.

    Directory of Open Access Journals (Sweden)

    Xiangrong Dong

    Full Text Available PprI is a general switch protein that regulates the expression of certain proteins involved in pathways of cellular resistance in the extremophilic bacterium Deinococcus radiodurans. In this study, we transformed pprI into Lactococcus lactis strain MG1363 using the lactococcal shuttle vector pMG36e and investigated its effects on the tolerance and lactic acid production of L. lactis while under stress. PprI was stably expressed in L. lactis as confirmed by western blot assays. L. lactis expressing PprI exhibited significantly improved resistance to oxidative stress and high osmotic pressure. This enhanced cellular tolerance to stressors might be due to the regulation of resistance-related genes (e.g., recA, recO, sodA, and nah by pprI. Moreover, transformed L. lactis demonstrated increased lactic acid production, attributed to enhanced lactate dehydrogenase activity. These results suggest that pprI can improve the tolerance of L. lactis to environmental stresses, and this transformed bacterial strain is a promising candidate for industrial applications of lactic acid production.

  6. Expression of PprI from Deinococcus radiodurans Improves Lactic Acid Production and Stress Tolerance in Lactococcus lactis.

    Science.gov (United States)

    Dong, Xiangrong; Tian, Bing; Dai, Shang; Li, Tao; Guo, Linna; Tan, Zhongfang; Jiao, Zhen; Jin, Qingsheng; Wang, Yanping; Hua, Yuejin

    2015-01-01

    PprI is a general switch protein that regulates the expression of certain proteins involved in pathways of cellular resistance in the extremophilic bacterium Deinococcus radiodurans. In this study, we transformed pprI into Lactococcus lactis strain MG1363 using the lactococcal shuttle vector pMG36e and investigated its effects on the tolerance and lactic acid production of L. lactis while under stress. PprI was stably expressed in L. lactis as confirmed by western blot assays. L. lactis expressing PprI exhibited significantly improved resistance to oxidative stress and high osmotic pressure. This enhanced cellular tolerance to stressors might be due to the regulation of resistance-related genes (e.g., recA, recO, sodA, and nah) by pprI. Moreover, transformed L. lactis demonstrated increased lactic acid production, attributed to enhanced lactate dehydrogenase activity. These results suggest that pprI can improve the tolerance of L. lactis to environmental stresses, and this transformed bacterial strain is a promising candidate for industrial applications of lactic acid production.

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

    OpenAIRE

    Érico Leandro da Silveira; Rodrigo Matheus Pereira; Denilson César Scaquitto; Eliamar Aparecida Nascimbém Pedrinho; Silvana Pómpeia Val-Moraes; Ester Wickert; Lúcia Maria Carareto-Alves; Eliana Gertrudes Macedo Lemos

    2006-01-01

    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 diversi...

  8. Infecção por Salmonella typhimurium de origem hídrica em garça gigante (Casmerodius albus egretta, em sua vida livre no Estado do Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Maria do Amparo Queiroz de Freitas

    1977-10-01

    Full Text Available De uma mortandade de garças de vida livre, no Estado do Rio de Janeiro, Brasil, foi isolada Salmonella typhimurium por hemocultura de material proveniente de uma ave que se mostrava enferma e que à necrópsia não apresentavam lesões a na tomopa tológicas. A Salmonella typhimurium foi também isolada de água de um lago existente no Jardim Zoológico do Rio de Janeiro, onde as aves tinham acesso permanente. Durante a mortandade das aves foi observada uma hepatite necrótica na qual havia colônias bacterianas, tesões atribuídas a esta salmonelose.

  9. Por que sou rondoniano

    Directory of Open Access Journals (Sweden)

    Mércio Pereira Gomes

    2009-01-01

    Full Text Available Numa revisão contextualizada no tempo e projetada pelos seus resultados, a obra do sertanista marechal Cândido Rondon (1867-1958 é avaliada positivamente pela dedicação à causa dos povos indígenas do Brasil, pela formação de uma ética de respeito do brasileiro para com os índios e pela institucionalização do dever do Estado brasileiro de proteger, assistir e ajudar os povos indígenas a manterem-se coesos e autônomos e ao mesmo tempo se projetarem no mundo mais amplo. A vida de Rondon é acompanhada desde a sua formação como cadete da Escola Militar, como membro da Igreja do Apostolado Positivista, como comandante da Expedição Rondon (1907-1930, que levou o telégrafo de Cuiabá a Porto Velho, e especialmente como criador e dirigente-mor do Serviço de Proteção aos Índios (SPI, 1910-1967. Rondon é o criador da expressão "Morrer se preciso for, matar nunca", que pautou a ação de indigenistas brasileiros que fizeram os primeiros contatos com muitos povos indígenas desde 1910. E muitos morreram seguindo essa norma, numa clara demonstração do novo espírito humanista criado pela atitude rondoniana. O indigenismo brasileiro implantado por Rondon teve altos e baixos ao longo de quase cem anos, que hoje prossegue pela Fundação Nacional do Índio (Funai. De fato, muitos povos indígenas perderam suas terras e muitos foram dizimados no século XX, mas os mais de 220 que sobreviveram vêm crescendo em número, obtendo suas terras (13% do território nacional e conquistando novos espaços político-culturais no Brasil.This paper reviews the life and work of Brazilian Indianist Marshall Cândido Rondon. Rondon's life is marked by a profound dedication to the Brazilian Indian cause and to instilling in Brazilians a respect for Indian peoples. He influenced the Brazilian government in shaping a policy of protecting, assisting, and helping Indian peoples retain cohesive, self-determined societies. He also encouraged Indians to

  10. Porøse materialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2000-01-01

    Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

  11. The close relation between Lactococcus and Methanosaeta is a keystone for stable methane production from molasses wastewater in a UASB reactor.

    Science.gov (United States)

    Kim, Tae Gwan; Yun, Jeonghee; Cho, Kyung-Suk

    2015-10-01

    The up-flow anaerobic sludge blanket (UASB) reactor is a promising method for the treatment of high-strength industrial wastewaters due to advantage of its high treatment capacity and settleable suspended biomass retention. Molasses wastewater as a sugar-rich waste is one of the most valuable raw material for bioenergy production due to its high organic strength and bioavailability. Interpretation for complex interactions of microbial community structures and operational parameters can help to establish stable biogas production. RNA-based approach for biogas production systems is recommended for analysis of functionally active community members which are significantly underestimated. In this study, methane production and active microbial community were characterized in an UASB reactor using molasses wastewater as feedstock. The UASB reactor achieved a stable process performance at an organic loading rate of 1.7~13.8-g chemical oxygen demand (COD,·L(-1) day(-1); 87-95 % COD removal efficiencies), and the maximum methane production rate was 4.01 L-CH4·at 13.8 g-COD L(-1) day(-1). Lactococcus and Methanosaeta were comprised up to 84 and 80 % of the active bacterial and archaeal communities, respectively. Network analysis of reactor performance and microbial community revealed that Lactococcus and Methanosaeta were network hub nodes and positively correlated each other. In addition, they were positively correlated with methane production and organic loading rate, and they shared the other microbial hub nodes as neighbors. The results indicate that the close association between Lactococcus and Methanosaeta is responsible for the stable production of methane in the UASB reactor using molasses wastewater.

  12. New Antifungal Bacteriocin-Synthesizing Strains of Lactococcus lactis ssp. lactis as the Perspective Biopreservatives for Protection of Raw Smoked Sausages

    Directory of Open Access Journals (Sweden)

    L. G. Stoyanova

    2010-01-01

    Full Text Available Problem statement: Screening for the effective bacteriocin-synthesizing strains of Lactococcus lactis as the perspective biopreservatives was performed. We used a raw milk and dairy products from different climatic regions as well as from powerful drinks of mixed lactic acid and alcoholic fermentation: kurunga, kumiss and Iranian Dough, that were widely used by local population to prevent diseases. Approach: The special interest was paid to isolates of lactococci with antagonistic activity. According to their morphological, cultural, physiological, biochemical properties and sequence of 16S rRNA gene they were identified as Lactococcus lactis ssp. lactis. Only nine from the selected 94 strains expressed a broad spectrum of activity against Gram-positive and Gramnegative bacteria including pathogens (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Salmonella gallinarum, moulds (Aspergillus, Fusarium, Penicillium genera, as well as yeasts (Rhodotorula, Candida. Results: It reveals the unique biological properties for isolated natural strains of Lactococcus lactis species. Most effective new bacteriocin-synthesizing strains 194 and K-205 were isolated from raw cow milk and kurunga from Buryatia. These strains had high antibiotic activity up to 3600 and 2700 IU mL-1 as compared to nisin and up to 2500-1700 IU mL-1 as compared to fungicidal antibiotic nistatin. In our experiments we used raw smoked sausages that were infected with fungi. The identification of this infection showed the presence of Eurotium repens de Bary on the sausages. Treatment of the raw smoked sausages with cultural broth of L.lactis ssp. lactis 194 and K-205 inhibited growth of these microorganisms. After treatment the sausages had longer shelf-life and was in accordance with basal production data (Russian State Standard Specification 16131-86. Conclusion: The results of this study indicated that the treatment with

  13. Alterações patológicas em potros infectados por Actinobacillus equuli subsp. haemolyticus Pathological changes in foals infected with Actinobacillus equuli subsp. haemolyticus

    Directory of Open Access Journals (Sweden)

    Danilo Carloto Gomes

    2010-06-01

    Full Text Available Neste trabalho, são descritos dois casos fatais de septicemia com lesões embólicas causadas por Actinobacillus equuli subsp. haemolyticus em potros recém-nascidos. Em um dos animais, foram observados, na necropsia, pequenos nódulos esbranquiçados de aproximadamente 0,2cm de diâmetro na cortical dos rins e no outro havia uma área de coloração acinzentada no lobo diafragmático esquerdo do pulmão. As principais alterações microscópicas observadas no primeiro animal foram rins com infiltrado inflamatório multifocal a coalescente acentuado, com predomínio de neutrófilos, associado com áreas basofílicas levemente granulares compostas por grumos bacterianos. No segundo animal, o pulmão apresentava infiltrado inflamatório neutrofílico, edema, congestão e colônias bacterianas intravasculares. Em ambos os casos, colônias bacterianas foram encontradas disseminadas por vários órgãos incluindo capilares cerebrais. Nos dois casos foi isolado e identificado A. equuli subsp. haemolyticus.This paper describes two fatal cases of embolic and septicaemic lesions caused by Actinobacillus equuli subsp. haemolyticus in two newborn foals. In one foal was observed at necropsy small whitish nodules of approximately 0,2cm in diameter on the renal cortex and the other foal had an area of gray color in the left diaphragmatic lobe of the lung. The main histologic changes were observed in the first foal kidneys with multifocal to coalescing inflammatory suppurative infiltrates associated with slightly granular basophilic bacterial colonies. In the second animal the lung showed neutrophilic inflammatory infiltrate, edema, congestion and presence of intravascular bacterial colonies. In both cases, the bacteria were disseminated by several organs including cerebral capillary cerebral. In both cases A. equuli subsp. haemolyticus was isolated and identified.

  14. Application of the ligase chain reaction to the detection of nisinA and nisinZ genes in Lactococcus lactis ssp. lactis.

    Science.gov (United States)

    Ward, L J; Brown, J C; Davey, G P

    1994-03-15

    This paper reports on the application of the ligase chain reaction (LCR) to the specific detection of variants of the nisin structural gene (nisinA and nisinZ) in nisin producing strains of Lactococcus lactis ssp lactis. The LCR assay was used to screen nisin producing strains to determine which form of the nisin structural gene they contained. This method of differentiating the nisin structural gene variants provides a useful alternative to the only other available genetic differentiation, that of sequencing the gene.

  15. Identification of a Conserved Sequence in Flavoproteins Essential for the Correct Conformation and Activity of the NADH Oxidase NoxE of Lactococcus lactis ▿ †

    OpenAIRE

    Tachon, Sybille; Chambellon, Emilie; Yvon, Mireille

    2011-01-01

    Water-forming NADH oxidases (encoded by noxE, nox2, or nox) are flavoproteins generally implicated in the aerobic survival of microaerophilic bacteria, such as lactic acid bacteria. However, some natural Lactococcus lactis strains produce an inactive NoxE. We examined the role of NoxE in the oxygen tolerance of L. lactis in the rich synthetic medium GM17. Inactivation of noxE suppressed 95% of NADH oxidase activity but only slightly affected aerobic growth, oxidative stress resistance, and NA...

  16. Lactococcus garvieae endocarditis in a native valve identified by MALDI-TOF MS and PCR-based 16s rRNA in Spain: A case report

    Directory of Open Access Journals (Sweden)

    V. Heras Cañas

    2015-05-01

    Full Text Available Lactococcus garvieae is a Gram-positive, catalase negative coccus arranged in pairs or short chains, well-known as a fish pathogen. We report a case of Infective Endocarditis (IE by L. garvieae in a native valve from a 68-year-old male with unknown history of contact with raw fish and an extensive history of heart disease. This case highlights the reliability of MALDI-TOF MS compared to conventional methods in the identification of rare microorganisms like this.

  17. Lactococcus garvieae endocarditis in a native valve identified by MALDI-TOF MS and PCR-based 16s rRNA in Spain: A case report.

    Science.gov (United States)

    Heras Cañas, V; Pérez Ramirez, M D; Bermudez Jiménez, F; Rojo Martin, M D; Miranda Casas, C; Marin Arriaza, M; Navarro Marí, J M

    2015-05-01

    Lactococcus garvieae is a Gram-positive, catalase negative coccus arranged in pairs or short chains, well-known as a fish pathogen. We report a case of Infective Endocarditis (IE) by L. garvieae in a native valve from a 68-year-old male with unknown history of contact with raw fish and an extensive history of heart disease. This case highlights the reliability of MALDI-TOF MS compared to conventional methods in the identification of rare microorganisms like this.

  18. Meningitis por Kluyvera sp. en una paciente con una derivación lumbo-peritoneal: reporte de un caso

    Directory of Open Access Journals (Sweden)

    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.We describe the case of a female patient with a previous lumboperitoneal shunt, who developed bacterial meningitis Kluyvera sp. was isolated from the cerebrospinal fluid. To our knowledge this is the first case of CNS infection by this microorganism. This pathogen was very sensitive to third generation cephalosporins; and was treated succesfully with cefotaxime. The Kluyver genus comprises three species who are uncommonly isolated from clinical samples. It can be associated with mild to severe infections and is more common in inmunosuppressed hosts.

  19. Avaliação da resposta inflamatória traqueal ao curativo de celulose bacteriana após escarificação cirúrgica em coelhos Tracheal inflammatory response to bacterial cellulose dressing after surgical scarification in rabbits

    Directory of Open Access Journals (Sweden)

    Angelo D'urso Panerari

    2008-08-01

    Full Text Available Dentre as causas de insucesso nas cirurgias para a estenose traqueal está a formação de tecidos de cicatrização exuberantes. O uso de curativos para evitar esta reação pode ser de grande valia nestes casos. A celulose bacteriana produzida por acetobacter xylinun pode ser útil nestes casos. Não há estudos na região laringotraqueal. OBJETIVO: Avaliar a resposta tecidual subglótica de coelhos após escarificação e colocação de curativo de celulose, comparando com grupo controle. FORMA DE ESTUDO: Experimental MATERIAL E MÉTODOS: Foram estudados 26 coelhos, submetidos a escarificação da região laringotraqueal e tratados com curativo e comparados com controle. Foram estabelecidos 4 tempos de seguimento. Os seguimentos laringotraqueais foram examinados histologicamente e os resultados foram avaliados estaticamente. RESULTADOS: O grupo de estudo evoluiu com o passar do tempo com resultados estatisticamente semelhantes ao do grupo controle, nos parâmetros Congestão vascular, Exsudato purulento, Inflamação aguda, Integridade do epitélio, Proliferação fibrosa e Reação granulomatosa. CONCLUSÃO: Não foram observadas diferenças entre os grupos controle e de estudo quanto aos parâmetros inflamatórios ou cicatriciais. Não houve sinais inflamatórios relacionados ao uso da membrana de celulose que não tivessem ocorrido devido ao traumatismo cirúrgico.Exuberant scarring tissue formation is among the failure causes of tracheal stenosis surgery. Dressings that could avoid such reaction could be very helpful in these cases. Bacterial cellulose, produced by acetobacter xylinun can be useful in these cases. There are no studies in the laryngotracheal region. AIM: to assess subglottic tissue response in rabbits after scarification and placement of cellulose dressing, and comparing it to a control group. STUDY DESIGN: experimental. MATERIALS AND METHODS: 26 rabbits underwent laryngotracheal scarification, received the dressing and

  20. Increased biomass yield of Lactococcus lactis by reduced overconsumption of amino acids and increased catalytic activities of enzymes.

    Directory of Open Access Journals (Sweden)

    Kaarel Adamberg

    Full Text Available Steady state cultivation and multidimensional data analysis (metabolic fluxes, absolute proteome, and transcriptome are used to identify parameters that control the increase in biomass yield of Lactococcus lactis from 0.10 to 0.12 C-mol C-mol(-1 with an increase in specific growth rate by 5 times from 0.1 to 0.5 h(-1. Reorganization of amino acid consumption was expressed by the inactivation of the arginine deiminase pathway at a specific growth rate of 0.35 h(-1 followed by reduced over-consumption of pyruvate directed amino acids (asparagine, serine, threonine, alanine and cysteine until almost all consumed amino acids were used only for protein synthesis at maximal specific growth rate. This balanced growth was characterized by a high glycolytic flux carrying up to 87% of the carbon flow and only amino acids that relate to nucleotide synthesis (glutamine, serine and asparagine were consumed in higher amounts than required for cellular protein synthesis. Changes in the proteome were minor (mainly increase in the translation apparatus. Instead, the apparent catalytic activities of enzymes and ribosomes increased by 3.5 times (0.1 vs 0.5 h(-1. The apparent catalytic activities of glycolytic enzymes and ribosomal proteins were seen to follow this regulation pattern while those of enzymes involved in nucleotide metabolism increased more than the specific growth rate (over 5.5 times. Nucleotide synthesis formed the most abundant biomonomer synthetic pathway in the cells with an expenditure of 6% from the total ATP required for biosynthesis. Due to the increase in apparent catalytic activity, ribosome translation was more efficient at higher growth rates as evidenced by a decrease of protein to mRNA ratios. All these effects resulted in a 30% decrease of calculated ATP spilling (0.1 vs 0.5 h(-1. Our results show that bioprocesses can be made more efficient (using a balanced metabolism by varying the growth conditions.