Spelling suggestions: "subject:"enterobacteriaceae""
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Characterizing the Interaction Between Candida albicans and Two Enterobacter SpeciesCornett, Abigail 01 May 2022 (has links)
Candida albicans is the most common human fungal pathogen. The relationship between C. albicans and Enterobacter bacteria have yet to be explored. The hypothesis of this study is that C. albicans and both E. aerogenes and E. cloacae have a positive relationship and work together to infect the host. In this study, the physical cell-to-cell interaction, molecular components of said interaction, and the impact of the interaction on a live organism were explored. Results indicate that Enterobacter adheres to C. albicans and inhibits growth with unidentified secreted molecules. Als1p has potential involvement in the attachment of E. cloacae to C. albicans. Out of 480 E. cloacae mutants, 6 showed reductions in attachment to C. albicans. The presence of C. albicans in C. elegans may lead to less Enterobacter colonization. Future work involving this interaction should strive to identify the Enterobacter secreted molecules and genes necessary for their production.
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Knockout of the <i>lacZ gene in Enterobacter </i> sp. YSUFord, Kelsey L. 23 August 2018 (has links)
No description available.
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Cloning and Sequencing of Mercury Resistance Operons from the Enterobacter sp. YSU and Stenotrophomonas maltophilia OR02Muhindi, Stephen W. 07 May 2018 (has links)
No description available.
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Proteomic Characterization of Selenite Resistance in a strain of Enterobacter cloacaeBarasa, Nathaniel Wafula 16 September 2008 (has links)
No description available.
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Pathogenesis, immunity, and prevention of human norovirus infection in gnotobiotic pigsLei, Shaohua 23 April 2018 (has links)
Human noroviruses (HuNoVs) are the leading cause of viral epidemic acute gastroenteritis and responsible for the deaths of over 200,000 children each year worldwide. HuNoV research has been hampered by the long absence of a readily reproducible cell culture system and a suitable small animal model, while gnotobiotic (Gn) pigs have been a unique animal model for understanding HuNoV pathogenesis and immunity, as well as evaluating vaccine and therapeutics. Recent reports of HuNoVs infection and replication in B cells supplemented with commensal bacteria Enterobacter cloacae and in Blab/c mice deficient in RAG/IL2RG have gained extensive attention, and my studies utilized the well-established Gn pig model to investigate the effects of these two interventions on HuNoV infection. Surprisingly, the colonization of E. cloacae inhibited HuNoV infectivity in Gn pigs, evidenced by the significantly reduced HuNoV shedding in feces and HuNoV titers in intestinal tissues and blood compared to control pigs. Moreover, HuNoV infection of enterocytes but not B cells was observed with or without E. cloacae colonization, indicating B cells were not a target cell type for HuNoV in Gn pigs. On the other hand, using RAG2/IL2RG deficient pigs generated by CRISPR/Cas9 system, with confirmed severe combined immunodeficiency, I evaluated the effects of host immune responses on HuNoV infection. Compared to wild-type Gn pigs, longer HuNoV shedding was observed in RAG2/IL2RG deficient pigs (16 versus 27 days), and higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs. In addition, I evaluated dietary interventions including probiotics and rice bran using Gn pig model of HuNoV infection and diarrhea. While the colonization of probiotic bacteria Lactobacillus rhamnosus GG (LGG) and Escherichia coli Nissle 1917 (EcN) in Gn pigs completely inhibited HuNoV fecal shedding, the two cocktail regimens, in which rice bran feeding started either 7 days prior to or 1 day after viral inoculation in the LGG+EcN colonized Gn pigs, exhibited dramatic anti-HuNoV effects, including reduced incidence and shorter duration of diarrhea, as well as shorter duration of virus fecal shedding. The anti-HuNoV effects of the cocktail regimens were associated with the enhanced IFN-𝛾⁺ T cell responses, increased production of intestinal IgA and IgG, and longer villus length. Taken together, my dissertation work improves our understanding of HuNoV infection and immunity, and further supports for Gn pigs as a valuable model for future studies of human enteric virus infection, host immunity, and interventions. / Ph. D. / Human noroviruses (HuNoVs) are the leading cause of viral epidemic acute gastroenteritis. Using the gnotobiotic pig model of HuNoV infection and diarrhea, we found that (1) the colonization of a commensal bacterium E. cloacae inhibited HuNoV infectivity, and B cells were not a target cell type for HuNoV in gnotobiotic pigs. (2) Increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs, which had severe combined immunodeficiency. (3) The dietary supplementation of rice bran and colonization of two probiotic bacteria significantly reduced HuNoV infectivity and diarrhea, and the beneficial effects were associated with enhanced intestinal immunity and health. Taken together, the dissertation work improves our understanding of HuNoV infection and immunity, and further supports for gnotobiotic pigs as a valuable model for future studies of human enteric virus infection, host immunity, and interventions.
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Estudo genotípico e fenotípico de bacilos Gram-negativos produtores de carbapenemase do tipo New Delhi metalo-β-lactamase / Genotypic and fenotypic study of Gram-negative bacilli producers carbapenemase type New Delhi metallo--β-lactamase.Campos, Juliana Coutinho 31 August 2017 (has links)
Os carbapenêmicos são os antimicrobianos mais amplamente utilizados no tratamento empírico de infecções graves por bacilos Gram-negativos. A pressão seletiva gerada pelo uso desses antimicrobianos ao longo das últimas três décadas contribuiu para a disseminação de enterobactérias e Gram-negativos não fermentadores produtores de carbapenemases, particularmente as do tipo KPC e NDM. Os genes que codificam essas enzimas usualmente estão localizados em plasmídeos e/ou transpósons. A hipótese atualmente mais aceita é que o gene blaNDM-1 seja uma quimera criada em Acinetobacter baumannii. A NDM-1 foi descrita em paciente proveniente da Índia e subsequentemente evidenciou-se sua ampla disseminação nesse país. A epidemiologia que tem sido observada nos casos detectados na Europa e Estados Unidos tem sido viagem à Índia, ou seja, sem casos autóctones. No Brasil, os primeiros casos foram identificados no Rio Grande do Sul, e a seguir no Rio de Janeiro e em São Paulo. Diferentemente dos casos da Europa e América do Norte, os casos do Brasil não tem relação epidemiológica com a Índia. O sequenciamento integral dos plasmídeos e cromossomos albergando o gene blaNDM permitirá entender como ocorre a disseminação desse mecanismo de resistência no Brasil. Para isso, foi avaliado o perfil de susceptibilidade dos isolados, bem como a capacidade conjugativa e clonalidade. Das vinte e oito amostras utilizadas neste trabalho, treze delas pertencem à espécie Enterobacter hormaechei, uma à espécie Citrobacter freundii, sete à espécie Escherichia coli, quatro à Klebsiella pneumoniae e três ao gênero Acinetobacter spp. Os primeiros isolados incluídos neste estudo (Escherichia coli e Enterobacter hormaechei produzindo NDM-1) foram isolados em agosto de 2013, de uma mesma amostra de swab retal de um paciente do Rio de Janeiro que nunca viajou para o exterior. O sequenciamento completo do DNA plasmidial utilizando a plataforma Illumina e a anotação de ambos os plasmídeos albergando o gene blaNDM-1 revelou que estes pertencem a grupos de incompatibilidade diferentes, IncFIIK (E. hormaechei) e IncX3 (E. coli), e abrigam um novo transpóson composto designado Tn3000. A comparação da sequência nucleotídica do Tn3000 com aquelas disponíveis no GenBank evidencia que a mesma estrutura está presente em plasmídeos de isolados da cidade de Porto Alegre e também em diferentes continentes. As espécies de Acinetobacter (A. radioresistens, A. ursingii e A. guillouiae) isoladas em São Paulo e Porto Alegre, possuem o gene blaNDM-1 albergados em um mesmo plasmídeo não tipável de 41.087 pb. A avaliação da clonalidade dos isolados de Enterobacter hormaechei \"subsp. oharae\" mostrou dois perfis diferentes através da técnica de PFGE, sendo que todos os microrganismos foram isolados de um surto no mesmo hospital no Rio de Janeiro. Isolados de Klebsiella pneumoniae de uma mesma paciente internada em hospital em Salvador, de sítios distintos - swab retal, hemocultura e urina, em ordem cronológica - obtiveram o mesmo perfil clonal pela técnica de PFGE. O mesmo ocorreu com três isolados de Escherichia coli, de um mesmo paciente do Rio de Janeiro, em amostras de swab retal. Os achados deste estudo evidenciam que no Brasil, Nepal, Marrocos e Índia há uma disseminação do gene blaNDM-1 mediada por um novo elemento móvel designado Tn3000 em enterobactérias. A detecção de um mesmo plasmídeo em diferentes espécies de Acinetobacter evidencia que neste gênero bacteriano, no Brasil, a disseminação do gene blaNDM-1 ocorre por conjugação. / Carbapenems are the antimicrobials most widely used in the empirical treatment of severe infections caused by Gram-negative bacilli. The selective pressure generated by the use of these antibiotics over the last three decades has contributed to the spread of enterobacteria and Gram-negative non-fermenting producing carbapenemases, mainly KPC and NDM. Genes encoding these enzymes are usually located in plasmids and/or transposons. Currently the most accepted hypothesis is that the blaNDM-1 gene is a chimera created in Acinetobacter baumannii. The NDM-1 was described in a patient from India and subsequently was reported to be broadly disseminate in this country. The epidemiology that has been observed in cases detected in Europe and United States is traveling to India, but no autochthonous cases. In Brazil, the first cases were identified in Rio Grande do Sul, and then in Rio de Janeiro and São Paulo. Differently from the cases described in Europe and North America, the cases from Brazil have no epidemiological link with India. The complete sequencing of plasmids and chromosomes harboring blaNDM gene will understanding how the dissemination of this resistance mechanism in Brazil occurs. In this work we will be evaluate the susceptibility profile of the isolates, and their conjugal capacity and clonality. Of the twenty-eight samples used in this study, thirteen of them belong to the species Enterobacter hormaechei, one to Citrobacter freundii, seven to Escherichia coli, four to Klebsiella pneumoniae and three to the genus Acinetobacter sp. The first two isolates included in this study (Escherichia coli and Enterobacter hormaechei) were isolated in August 2013, from the same rectal swab sample from a patient from Rio de Janeiro that never traveled abroad. Complete sequencing of plasmid DNA using Illumina platform and annotation of both plasmids harboring the blaNDM-1 gene revealed that they belong to different incompatibility groups, IncFIIK (E. hormaechei) and IncX3 (E. coli), and are harbor to a new transposon designated Tn3000. The comparison of the Tn3000 nucleotide sequence with those available at GenBank shows that the same structure is present in plasmids from other Porto Alegre and also in different continents. The Acinetobacter species (A. radioresistens, A. ursingii and A. guillouiae) isolated in São Paulo and Porto Alegre, have the blaNDM-1 gene harbored in a single non-typing plasmid of 41,087 bp. The evaluation of clonal relationship of Enterobacter hormaechei \"subsp. oharae\" showed two different profiles by PFGE technique; of note all microorganisms were isolated from an outbreak in the same hospital in Rio de Janeiro. Isolates of Klebsiella pneumoniae from a single patient hospitalized in Salvador, from different anatomical sites - rectal swab, blood culture and urine, in chronological order - obtained the same clonal profile by the PFGE technique. The same occurred with three Escherichia coli isolates, from the same patient from Rio de Janeiro, in swab rectal strains. Our findings suggest that in Brazil, Nepal, Morocco and India there is a spread of blaNDM-1 gene mediated by Tn3000 in enterobacteria. The detection of a same plasmid in different species of Acinetobacter shows that in this bacterial genus, in Brazil, the dissemination of the blaNDM-1 gene occurs by conjugation.
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PERFIL DE RESISTÊNCIA DAS BACTÉRIAS GRAM-NEGATIVAS COMUMENTE ASSOCIADAS À INFECÇÕES DO TRATO URINÁ- RIO EM IDOSOS EM GOIÂNIA – GO, NO PERÍODO DE 2011- 2015Povoa, Christiano Patricio 08 September 2016 (has links)
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Previous issue date: 2016-09-08 / The urinary tract infections (UTI) are one of the most common types of infection,
both community as nosocomial, the ITU is caused by bacteria are more common
in men and in. The study was descriti-vo retrospective and prospective type, from
2011 to 2016 were analyzed from 3388 antibiograms of ITU of Community origin
in the elderly. The age of patients ranged from 60 to 100 years, with a mean age
of 73 years, and 77.28% occurred in women and 22.72% in men. The microranalyzed
organisms were Escherichia coli (75.65%) with 80.72% by Women's
res and 19.28% in men, followed by Klebsiella pneumoniae (16.59%) with
66.73% infection 33.27% in women and in men. Proteus spp. It was respon-sible
for 5.70% cases, with 70.47% occurred in women and 29.53% in ho-mens. Enterobacter
spp. It was the causative organism of UTI in 2.07%; 45.71% women and
54.29% in men. The highest prevalence of resistance to E. coli were to sulfonamide
(40.54%), Ciprofloxacin (35.04%), Nalidixic acid (34.92%), Cephalosporins
1st Generation (31,45%), Norfloxacin (24 , 50%), Penicillin (23.68%) and 3rd generation
cephalosporins (12.29%), an increase in the evolution of resistance to
cephalosporins 2nd generation (p = 0.0074). For K. pneumoniae, the major resistance
prevalence occurs to ram for Norfloxacin (16.73%), cephalosporins 3rd
Generation (20.46%), Aci-of Nalidixic (26.87%), Cephalosporins 1st Generation
(29 , 00%), Penicillin (33.99%), sulfonamide (35.05%), Nitrofurantoin (37.90%),
Gemifloxacin (46.09%) and ofloxacin (46.09%) with increased resistance evolution
Carbapenems for (p = 0.0271) and Cephalosporins 1st generation (p =
0.0496). Proteus spp., The major resistance prevalences were to Gati-floxacina
(12.95%), Norfloxacin (12.95%), penicillins (14.51%), cephalosporins on the 2nd
Generation (21.24%) , sulfonamide (36.27%), Cephalosporins 1st Ge-feed
(38.86%), Gemifloxacin (46.11%), ofloxacin (46.11%), nitrofurantoin (76.68%),
Nalidixic acid (81 , 87%) and levofloxacin (81.87%). For Enterobac-have spp.,
The major resistance prevalences were compared to Cefalospo-mandarins of 4th
Generation (15.71%), Gatifloxacin (21.43%), Norfloxacin (21.43%), Ciprofloxacin
(28.57 %), Moxifloxacin (28.57%), Nitrofurantoin (31.43%), 3rd generation cephalosporins
(32.86%), sulfonamide (38.57%), Gemifloxacin (42.86%), ofloxacin (42,
86%) 1st generation cephalosporins (44.29%), nalidixic acid (77.14%), Levofloxacin (77.14%) and Penicillins (97.14%) with au-ment in the evolution of resistance
to cephalosporins 2nd Generation (p = 0.0057). For empiric treatment of
complicated UTI due to the found resistance to the antimicrobials of choice, the
aminoglycosides, Carbapenems and monobactam can be used until they are
met, the causative agents of infection and susceptibility to tested Antimicro-bianos
and should be replaced by re-duced antimicrobial spectrum, but with high
power. / As infecções no trato urinário (ITU) correspondem a um dos tipos mais comuns
de infecção, tanto comunitária quanto nosocomial, sendo as ITU causadas por
bactérias são mais comuns, tanto em homens quanto em. O estudo foi descritivo
tipo retrospectivo e prospectivo, no período de 2011 a 2016. Foram analisados
3388 antibiogramas de ITU de origem comunitária em idosos. A faixa etária dos
pacientes variou de 60 até 100 anos, com média de idade de 73 anos, sendo
que 77,28% ocorreram em mulheres e 22,72% em homens. Os microrganismos
analisados foram Escherichia coli (75,65%), com 80,72% em mulheres e 19,28%
em homens, seguido por Klebsiella pneumoniae, (16,59%), com 66,73% infecções
em mulheres e 33,27% em homens. Proteus spp. foi responsável por 5,70%
casos, com 70,47% ocorreram em mulheres e 29,53% em homens. Enterobacter
spp. foi o organismo causador de ITU em 2,07%; 45,71% em mulheres e 54,29%
em homens. As maiores prevalências de resistência para E. coli foram para Sulfonamida
(40,54%), Ciprofloxacina (35,04%), Ácido Nalidíxico (34,92%), Cefalosporinas
de 1ª Geração (31,45%), Norfloxacina (24,50%), Penicilinas (23,68%)
e Cefalosporinas de 3ª Geração (12,29%), com aumento na evolução da resistência
para Cefalosporinas de 2ª Geração (p = 0,0074). Para K. pneumoniae, as
maiores prevalências de resistência ocorreram para Norfloxacina (16,73%), Cefalosporinas
de 3ª Geração (20,46%), Ácido Nalidíxico (26,87%), Cefalosporinas
de 1ª Geração (29,00%), Penicilinas (33,99%), Sulfonamida (35,05%), Nitrofurantoína
(37,90%), Gemifloxacina (46,09%) e Ofloxacina (46,09%) com aumento
na evolução da resistência para Carbapenêmicos (p = 0,0271) e Cefalosporinas
de 1ª Geração (p = 0,0496). Para Proteus spp., as maiores prevalências de resistência
foram para Gatifloxacina (12,95%), Norfloxacina (12,95%), Penicilinas
(14,51%), Cefalosporinas de 2ª Geração (21,24%), Sulfonamida (36,27%), Cefalosporinas
da 1ª Geração (38,86%), Gemifloxacina (46,11%), Ofloxacina
(46,11%), Nitrofurantoína (76,68%), Ácido Nalidíxico (81,87%) e Levofloxacina
(81,87%). Para Enterobacter spp., as maiores prevalências de resistência foram
em relação à Cefalosporinas de 4ª Geração (15,71%), Gatifloxacina (21,43%),
Norfloxacina (21,43%), Ciprofloxacina (28,57%), Moxifloxacina (28,57%), Nitrofurantoína
(31,43%), Cefalosporinas de 3ª Geração (32,86%), Sulfonamida
(38,57%), Gemifloxacina (42,86%), Ofloxacina (42,86%), Cefalosporinas de 1ª Geração (44,29%), Ácido Nalidíxico (77,14%), Levofloxacina (77,14%) e Penicilinas
(97,14%), com aumento na evolução da resistência para Cefalosporinas de
2ª Geração (p = 0,0057). Para o tratamento empírico das ITU complicadas, devido
à resistência encontrada para os antimicrobianos de primeira escolha, podem
ser usados os Aminoglicosídeos, Carbapenêmicos e Monobactama, até que
sejam conhecidos os agentes causadores das infecções e a susceptibilidade aos
antimicrobianos testados, devendo ser substituídos por antimicrobiano de espectro
reduzido, porém com potência elevada.
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Estudo genotípico e fenotípico de bacilos Gram-negativos produtores de carbapenemase do tipo New Delhi metalo-β-lactamase / Genotypic and fenotypic study of Gram-negative bacilli producers carbapenemase type New Delhi metallo--β-lactamase.Juliana Coutinho Campos 31 August 2017 (has links)
Os carbapenêmicos são os antimicrobianos mais amplamente utilizados no tratamento empírico de infecções graves por bacilos Gram-negativos. A pressão seletiva gerada pelo uso desses antimicrobianos ao longo das últimas três décadas contribuiu para a disseminação de enterobactérias e Gram-negativos não fermentadores produtores de carbapenemases, particularmente as do tipo KPC e NDM. Os genes que codificam essas enzimas usualmente estão localizados em plasmídeos e/ou transpósons. A hipótese atualmente mais aceita é que o gene blaNDM-1 seja uma quimera criada em Acinetobacter baumannii. A NDM-1 foi descrita em paciente proveniente da Índia e subsequentemente evidenciou-se sua ampla disseminação nesse país. A epidemiologia que tem sido observada nos casos detectados na Europa e Estados Unidos tem sido viagem à Índia, ou seja, sem casos autóctones. No Brasil, os primeiros casos foram identificados no Rio Grande do Sul, e a seguir no Rio de Janeiro e em São Paulo. Diferentemente dos casos da Europa e América do Norte, os casos do Brasil não tem relação epidemiológica com a Índia. O sequenciamento integral dos plasmídeos e cromossomos albergando o gene blaNDM permitirá entender como ocorre a disseminação desse mecanismo de resistência no Brasil. Para isso, foi avaliado o perfil de susceptibilidade dos isolados, bem como a capacidade conjugativa e clonalidade. Das vinte e oito amostras utilizadas neste trabalho, treze delas pertencem à espécie Enterobacter hormaechei, uma à espécie Citrobacter freundii, sete à espécie Escherichia coli, quatro à Klebsiella pneumoniae e três ao gênero Acinetobacter spp. Os primeiros isolados incluídos neste estudo (Escherichia coli e Enterobacter hormaechei produzindo NDM-1) foram isolados em agosto de 2013, de uma mesma amostra de swab retal de um paciente do Rio de Janeiro que nunca viajou para o exterior. O sequenciamento completo do DNA plasmidial utilizando a plataforma Illumina e a anotação de ambos os plasmídeos albergando o gene blaNDM-1 revelou que estes pertencem a grupos de incompatibilidade diferentes, IncFIIK (E. hormaechei) e IncX3 (E. coli), e abrigam um novo transpóson composto designado Tn3000. A comparação da sequência nucleotídica do Tn3000 com aquelas disponíveis no GenBank evidencia que a mesma estrutura está presente em plasmídeos de isolados da cidade de Porto Alegre e também em diferentes continentes. As espécies de Acinetobacter (A. radioresistens, A. ursingii e A. guillouiae) isoladas em São Paulo e Porto Alegre, possuem o gene blaNDM-1 albergados em um mesmo plasmídeo não tipável de 41.087 pb. A avaliação da clonalidade dos isolados de Enterobacter hormaechei \"subsp. oharae\" mostrou dois perfis diferentes através da técnica de PFGE, sendo que todos os microrganismos foram isolados de um surto no mesmo hospital no Rio de Janeiro. Isolados de Klebsiella pneumoniae de uma mesma paciente internada em hospital em Salvador, de sítios distintos - swab retal, hemocultura e urina, em ordem cronológica - obtiveram o mesmo perfil clonal pela técnica de PFGE. O mesmo ocorreu com três isolados de Escherichia coli, de um mesmo paciente do Rio de Janeiro, em amostras de swab retal. Os achados deste estudo evidenciam que no Brasil, Nepal, Marrocos e Índia há uma disseminação do gene blaNDM-1 mediada por um novo elemento móvel designado Tn3000 em enterobactérias. A detecção de um mesmo plasmídeo em diferentes espécies de Acinetobacter evidencia que neste gênero bacteriano, no Brasil, a disseminação do gene blaNDM-1 ocorre por conjugação. / Carbapenems are the antimicrobials most widely used in the empirical treatment of severe infections caused by Gram-negative bacilli. The selective pressure generated by the use of these antibiotics over the last three decades has contributed to the spread of enterobacteria and Gram-negative non-fermenting producing carbapenemases, mainly KPC and NDM. Genes encoding these enzymes are usually located in plasmids and/or transposons. Currently the most accepted hypothesis is that the blaNDM-1 gene is a chimera created in Acinetobacter baumannii. The NDM-1 was described in a patient from India and subsequently was reported to be broadly disseminate in this country. The epidemiology that has been observed in cases detected in Europe and United States is traveling to India, but no autochthonous cases. In Brazil, the first cases were identified in Rio Grande do Sul, and then in Rio de Janeiro and São Paulo. Differently from the cases described in Europe and North America, the cases from Brazil have no epidemiological link with India. The complete sequencing of plasmids and chromosomes harboring blaNDM gene will understanding how the dissemination of this resistance mechanism in Brazil occurs. In this work we will be evaluate the susceptibility profile of the isolates, and their conjugal capacity and clonality. Of the twenty-eight samples used in this study, thirteen of them belong to the species Enterobacter hormaechei, one to Citrobacter freundii, seven to Escherichia coli, four to Klebsiella pneumoniae and three to the genus Acinetobacter sp. The first two isolates included in this study (Escherichia coli and Enterobacter hormaechei) were isolated in August 2013, from the same rectal swab sample from a patient from Rio de Janeiro that never traveled abroad. Complete sequencing of plasmid DNA using Illumina platform and annotation of both plasmids harboring the blaNDM-1 gene revealed that they belong to different incompatibility groups, IncFIIK (E. hormaechei) and IncX3 (E. coli), and are harbor to a new transposon designated Tn3000. The comparison of the Tn3000 nucleotide sequence with those available at GenBank shows that the same structure is present in plasmids from other Porto Alegre and also in different continents. The Acinetobacter species (A. radioresistens, A. ursingii and A. guillouiae) isolated in São Paulo and Porto Alegre, have the blaNDM-1 gene harbored in a single non-typing plasmid of 41,087 bp. The evaluation of clonal relationship of Enterobacter hormaechei \"subsp. oharae\" showed two different profiles by PFGE technique; of note all microorganisms were isolated from an outbreak in the same hospital in Rio de Janeiro. Isolates of Klebsiella pneumoniae from a single patient hospitalized in Salvador, from different anatomical sites - rectal swab, blood culture and urine, in chronological order - obtained the same clonal profile by the PFGE technique. The same occurred with three Escherichia coli isolates, from the same patient from Rio de Janeiro, in swab rectal strains. Our findings suggest that in Brazil, Nepal, Morocco and India there is a spread of blaNDM-1 gene mediated by Tn3000 in enterobacteria. The detection of a same plasmid in different species of Acinetobacter shows that in this bacterial genus, in Brazil, the dissemination of the blaNDM-1 gene occurs by conjugation.
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Enterobactérias e fatores de virulência em cepas de Escherichia coli isoladas de psitacídeos / Enterobacteriaceae and virulence factors in strains of Escherichia coli isolated from psittacines birdsCorrêa, Isadora Mainieri de Oliveira 17 February 2012 (has links)
Programa de Apoio aos Planos de Reestruturação e Expansão das Universidades Federais / The microbiota intestinal of Psittaciformes is mainly composed of Gram positive bacteria, is considered a sign of illness the presence of Gram negative bacteria. Wild birds are important to public health by harboring pathogens able of zoonotic transmission. The displacement of these birds, such as occurs in the trafficking of wild animals, is a propagation mechanism of new endemic foci of infections agents to long distances from where they were acquired. In this study we examined the presence of enterobacteria in psittacines using samples of organs of birds received for necropsy at the Laboratório Central de Diagnóstico de Patologias Aviárias (LCDPA) situate in the Departamento de Medicina Veterinária Preventiva (DMVP) at Centro de Ciências Rurais (CCR) of the Universidade Federal de Santa Maria (UFSM). We also collected samples using swabs of cloaca and crop, in live birds, kept in captivity in order to monitor the possible presence of pathogenic bacteria. Escherichia coli was considered the predominant bacteria in most samples, then after microbiological analysis and confirmation of E. coli isolates, we selected 28 colonies, which were tested for virulence factors iss, this gen is associated with the strain s ability to resist the lytic effects of serum, and iutA an outer membrane receptor of involved in the high affinity binding of iron-aerobactin. It is hoped that the data obtained in this research will help in establishing the health status of psittacines helping maintain the species and preventing risks to public health. / A microbiota intestinal de Psitaciformes é composta principalmente por bactérias Gram positivas, não se considerando saudável a presença de bactérias Gram negativas. As aves silvestres possuem importância para a saúde pública por albergarem patógenos passíveis de transmissão zoonótica. O deslocamento territorial dessas aves, como o que ocorre no tráfico de animais selvagens, constitui um mecanismo de propagação de novos focos endêmicos de agentes infecciosos a grandes distâncias dos locais onde foram adquiridos. Neste trabalho analisamos a presença de enterobactérias em psitacídeos utilizando amostras de órgãos de aves recebidas para necropsia na rotina do Laboratório Central de Diagnóstico de Patologias Aviárias (LCDPA) situado no Departamento de Medicina Veterinária Preventiva (DMVP) do Centro de Ciências Rurais (CCR) da Universidade Federal de Santa Maria (UFSM). Também foi realizada coleta de suabes cloacais e de inglúvio em aves vivas mantidas em cativeiro visando monitorar a presença de possíveis bactérias patogênicas. Escherichia coli foi considerada a bactéria predominante na maioria das amostras, então após análise microbiológica e confirmação dos isolados de E. coli, selecionamos 28 colônias, as quais foram testadas para os fatores de virulência iss, relacionado com a capacidade da cepa em resistir aos efeitos líticos do soro, e iutA, sendo este gene um receptor de membrana externa dos compostos sideróforos da aerobactina (genes iuc) que é um sistema de captação de ferro pelo qual E. coli expressa afinidade. Espera-se que os dados obtidos nessa pesquisa contribuam no estabelecimento do estado sanitário de psitaciformes auxiliando na manutenção da espécie e prevenindo riscos à saúde pública.
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Régulation de la perméabilité membranaire chez les bactéries à Gram négatif et la relation avec la sensibilité aux antibiotiques / Regulation of membrane permeability in Gram-negative bacteria and its relation to antibiotic susceptibilityMolitor, Alexander 19 March 2010 (has links)
La perméabilité membranaire joue un rôle important dans la résistance aux antibiotiques chez lesbactéries à Gram négatif.L’objectif de notre travail était de caractériser la fonction tenue par les deux régulateurs globaux dela perméabilité membranaire chez Enterobacer aerogenes: mar et ram. L’objectif initial futd’identifier le répresseur spécifique de RamA qui manquait en tant qu’élément de la cascade derégulation actuellement définie. La sélection de 60 souches nous a permis de confirmer le rôlecentral joué par RamA dans la régulation, ainsi qu’identifier des mutations pouvant être critiques, auniveau de RamR. Ainsi, l’absence variations observées dans le régulon marRAB et l’expressionmodérée des transcrits montrée par qRT-PCR laisse penser, que RamA a un rôle clef dans larégulation de l’expression des porines et des pompes d’efflux chez E. aerogenes.L’autre partie de notre travail reposait sur l’étude de la translocation des antibiotiques au traversdes porines. L’étude des interactions porine-carbapénèmes s’est faite sur la porine sauvage OmpFd'Escherichia coli et deux mutations. Les résultats indiquent également l'importance de l'aspartateen position 113 dans la sélectivité de translocation des carbapénèmes au sein de la porine OmpF.Ce travail montre ainsi que la translocation des pénicillines est aussi sous la dépendance desinteractions qui se créent entre le substrat et le résidu en position 113 de OmpF et limitent alorsleur passage au niveau du canal porine. Nous avons recherché la contribution attribuée à la porineOmp36 d'E. aerogenes dans la translocation de certaines béta-lactamines. Les mesures ont permisde conclure que les deux beta-lactamin / Genetic permeability plays an important role in antibiotic resistance of Gram-negative bacteria.Our work was to characterize and better understand of the genetic regulation of membranepermeability in E. aerogenes. We focused on two global regulators, mar and ram, in about 60clinical isolates. Alterations in the upstream region of ramA and in ramR but no mutations in marAnor marR were observed. Overexpression of ramA or ramR led to an altered antibiotic susceptibilityassociated to decrease of porins expression and over-expression of efflux-pumps. qRT-PCR pointedout the estimated importance of the ram-regulon in the regulation cascade.Another part of this work was to characterize the translocation of compounds through porins andthe role of porins in drug uptake in general. Measurement of the rate of antibiotic action of threecarbapenems in an E. coli strain solely expressing OmpF as porin clearly indicated the importanceof the aspartate at position 113 in antibiotic translocation. A multi-disciplinary three way approachof computer modeling, black-lipid-bilayer assays and measurement of antibiotic action, suggestedthat interactions with residue D113 of E. coli porin OmpF are rate-limiting for transport throughthe porin channel. Combination of biological and biophysical measurements with E. aerogenesporin Omp36 denoted that interactions between the porin channel and the antibiotic facilitate andaccelerate transport.
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