Escherichia coli enteropatogênica atípica (EPECa) é causadora de diarréia infantil e apresenta alta heterogeneidade quanto aos fatores de virulência. O objetivo deste trabalho foi estudar o comportamento de EPECa na interação com fagócitos profissionais. Duas amostras de EPECa sorotipo O55:H7 mostraram-se capazes de reduzir a fagocitose. Os sobrenadantes dos cultivos foram submetidos a SPE e HPLC e as frações com efeito antifagocítico foram submetidas a espectrometria de massas. A fração capaz de reduzir a fagocitose de bactérias reduziu também a fagocitose de Saccharomyces cerevisiae. Além de mostrar que EPECa é capaz de induzir a antifagocitose, mostrou-se também que o fator antifagocitico é secretado, solúvel em meio aquoso, termoestável, apresenta baixo peso molecular, não é microbicida ou citotóxico e, por último, há indicativos de que possa apresentar uma região glicosídica. Estes achados sugerem que o fator antifagocítico pode, embora não sozinho, exercer um papel importante na adaptabilidade e patogenicidade das EPECa. / Atypical enteropathogenic Escherichia coli (aEPEC) causes diarrhea mainly in children and presents a high heterogeneity of virulence factors. The objective of this work was to study the behavior of aEPEC regarding its interaction with professional phagocytes. Two samples of aEPEC serotype O55:H7 were able to reduce phagocytosis, The culture supernatants were submitted to SPE and HPLC and the active fractions were tested and analyzed by mass spectrometry. The results show that the fraction with bacterial antiphagocytic activity also reduces phagocytosis of Saccharomyces cerevisiae. In addition to demonstrating that aEPEC can induce antiphagocytosis, this work shows that it is due to a secreted antiphagocytic factor that is soluble in aqueous medium, is thermo-stable, has a low molecular weight, is not bactericide or cytotoxic and, finally, possibly presents a glycosidic region. These findings suggest that the antiphagocytic factor may, though maybe not alone, play an important role in the adaptability and pathogenicity of aEPEC.

Enterobactérias são importantes agentes de infecção podendo contaminar ambientes aquáticos poluídos por atividades antropogênicas, os quais podem ser importantes locais para a seleção e disseminação de bactérias resistentes aos antibacterianos (ATB) de uso na medicina humana e veterinária. O objetivo desse estudo foi monitorar a disseminação de enterobactérias resistentes aos ATB em ambientes aquáticos do estado de São Paulo. De 2009-2010, 135 enterobactérias resistentes à pelo menos um ATB, foram isoladas de rios, represas e estações de tratamento de esgoto. O fenótipo multirresistente (MR) foi predominante em 64% dos isolados, sendo que houve um predomino de E. coli (80%) e K. pneumoniae (48%). Oito porcento dos isolados apresentaram fenótipo ESBL (cefotaxima, CIM50 <font face=\"Symbol\">&#8805; 64 <font face=\"Symbol\">mg/ml) devido à presença de genes blaCTX-M-like, enquanto que a presença de genes qnr-like foi confirmada em 7% dos isolados resistentes à ciprofloxacina (CIM50 <font face=\"Symbol\">&#8805; 32<font face=\"Symbol\">mg/ml). A tipagem molecular revelou ausência de relação clonal entre os isolados de K. pneumoniae e E. coli. / Enterobacteria are important agents of infection may contaminate aquatic environments polluted by anthropogenic activities, which may be important sites for the selection and spread of bacteria resistant to antibiotics (ATB) for use in human and veterinary medicine. The aim of this study was to monitor the spread of enterobacteria resistant to ATB in aquatic environments of the state of Sao Paulo. From 2009-2010, 135 Enterobacteriaceae resistant to at least one ATB, were isolated from rivers, dams and sewage treatment plants. The phenotype resistant (MDR) was predominant in 64% of the isolates, and there was the predominance of E. coli (80%) and K pneumoniae (48%). Eight percent of the isolates showed ESBL phenotype (cefotaxime, MIC50 <font face=\"Symbol\">&#8805; 64 <font face=\"Symbol\">mg/ml) due to the presence of blaCTX-M-like, while the presence qnr-like gene was confirmed in 7% of isolates resistant to (ciprofloxacin MIC50 <font face=\"Symbol\">&#8805; 32<font face=\"Symbol\">mg/ml). Molecular typing revealed no clonal relationship among isolates of K. pneumoniae and E. coli.

O presente estudo visou determinar a prevalência de bactérias Gram-negativas produtoras de produzem b-lactamases de amplo espectro (ESBL) e resistência adquirida a quinolonas mediada por plasmídeos (PMQR) em animais de estimação, investigando o potencial papel destes hospedeiros como portadores assintomáticos. Em 2012, foram coletadas 216 amostras (fezes e saliva) de 108 animais de companhia (29 gatos e 79 cães) abrigados em casas de família, um centro de acolhimento de animais abandonados, e no Centro de Controle de Zoonoses da Cidade de São Paulo. Do total de cepas estudadas, 85% apresentaram fenótipo sugestivo de PMQR; enquanto que 62% dos isolados exibiram um fenótipo característico e sugestivo para produção de ESBL, sendo na sua maioria identificadas como E. coli. Dentre os isolados, 14 carregaram variantes do gene blaCTX-M, 9 foram positivos para o gene blaTEM, e 6 foram positivos para blaSHV. Em relação às cepas resistentes às Q/FQ, 56% (n= 43) foram positivas para a presença do gene qnr, o qual foi identificado em 11 espécies diferentes. Os resultados apresentados demostram que animais de companhia podem ser portadores assintomáticos de cepas produtoras de ESBL e PMQR. / The present study aimed to determine the prevalence of Gram-negative bacteria producing b-lactamases producing broad-spectrum (ESBL) and acquired resistance to quinolones mediated by plasmids (PMQR) in pets, investigating the potential role of these hosts as asymptomatic carriers. In 2012, 216 samples (feces and saliva) of 108 companion animals (29 cats and 79 dogs) housed in shelters or a Zoonosis Control Center were collected from São Paulo city. Of the total strains studied, 85% had a phenotype suggestive for PMQR; while 62 % of the isolates exhibited a characteristic phenotype and suggestive for ESBL-producing genes, with the most identified as E. coli. Among the isolates, 14 carried variants blaCTX -M gene 9 were positive for blaTEM gene, and 6 were positive for blaSHV. Regarding resistant Q/FQ isolates, 56% (n = 43) were positive for the presence of qnr gene, which was identified on 11 different species. The results presented demonstrate that pets can be asymptomatic carriers of ESBL producing strains and PMQR.

Made available in DSpace on 2014-08-20T13:42:09Z (GMT). No. of bitstreams: 1 Dissertacao_Tatiane_Kuka_Valente_Gandra.pdf: 6435400 bytes, checksum: eb0efa5223904e377b05e07ae3b1061e (MD5) Previous issue date: 2011-02-23 / Meat is one of the most important population diet items and has fundamental importance for the economy of the country. However, both for effective consoledation of Brazilian fresh beef exports to other markets, such as to offer domestic products with nutrition quality and food security is essential for maintaining an adequate shelf life and an acceptable microbiological quality of these products. In this context, this study was carried out to verify the microbiological quality by Salmonella spp., mesophilic aerobic microorganisms and Enterobacteriaceae quantification on bovine carcasses from two abattoirs-slaughterhouses with different levels of sanitary inspection (federal and state), located in southern Rio Grande do Sul and beyond, curtailments, equipment surfaces, utensils, and hands of food handlers, in the slaughterhouse for state inspection. Sixty cattle carcasses were evaluated two abattoirs-slaughterhouses, in four points in the slaughter line (after bleeding, after skinning, after evisceration, after washing and before cooling), totaling 240 samples. In the state inspection slaughterhouse the carcasses were sampled environmental surface slaughtering and processing (sawing open the breastbone, sawing the division of carcasses, table, knife and handlers) and two cuts (loin and fillet) totaling 52 samples. For statistical evaluation of results was carried out an analysis of variance followed by Tukey test and determining the correlation coefficients between microbial concentrations recorded in the sampled points. Among the points studied showed higher concentrations of mesophilic aerobic micro-organisms and Enterobactericeae as well as the presence of Salmonella spp. at the collection point after bleeding, indicating that the leather of cattle is a introduction source of microorganisms in the environment two abattoirs-slaughterhouses, and that the operations of hygiene and sanitation leather cattle before slaughter were not effective for prevent entry of these microorganisms in the environment of slaughter. From the scores of environmental surfaces found that the handlers are an important point of contamination in the state inspection slaughterhouse considering that showed significantly higher concentrations of mesophilic bacteria and Enterobactericeae in comparison with other items of the environment. Salmonella spp. was found in the leather of cattle, in the two abattoirs-slaughterhouses, however, was not detected in any other sample point of the slaughter line or in the environment and cuts, showing that the culling operations were effective to control contamination carcass and meat cuts for that microorganism. Finally, the slaughterhouses with different levels of sanitary inspection showed high correlation coefficients for the concentration of micro-organisms and aerobic mesophile (R=0,97) Enterobactericeae (R=0,91), and for the presence of Salmonella spp. no significant differences, indicating that the forms of contamination of carcasses during slaughter operations for these microorganisms are probably the same. / A carne é um dos itens mais importantes da dieta alimentar da população brasileira e possui fundamental importância para a economia do País. Contudo, tanto para consolidação efetiva da exportação brasileira de carne bovina in natura e de seus derivados a outros mercados, como para oferecer ao mercado interno produtos com qualidade nutricional e segurança alimentar é indispensável † manutenção de uma vida til adequada e de uma qualidade microbiológica aceitável para estes produtos. Neste contexto, este estudo foi realizado com intuito de verificar a qualidade microbiológica, através da pesquisa de Salmonella spp. e da quantificação de micro- organismos mesófilos aeróbios e de Enterobacteriaceae, em carcaças bovinas, provenientes de dois frigoríficos-matadouros com níveis de inspeção sanitária diferentes (estadual e federal), localizados na região sul do Rio Grande do Sul e, além destas, em cortes, superfícies de equipamentos, utensílios e m os de manipuladores, no frigorífico de Inspeção Estadual. Foram avaliadas 60 carcaças bovinas nos dois frigoríficos, em quatro pontos da linha de abate (após a sangria, após a esfola, após a eviscera€ o e após a lavagem pré-resfriamento), totalizando 240 amostras. No frigorífico com Inspeção Estadual, além das carcaças, foram amostradas superfícies do ambiente de abate e processamento (serra de abertura do esterno, serra de divisão das carcaças, mesa, faca e m os dos manipuladores) e dois cortes (alcatra e filé) que totalizaram 52 amostras. Para avalia€ o estatística dos resultados realizou-se uma análise de variância seguida do teste de Tuckey e determinaram-se coeficientes de correlação entre as concentrações microbianas verificadas nos pontos amostrados. Dentre os pontos avaliados verificaram-se maiores concentrações de micro-organismos mesófilos aeróbios e de Enterobactericeae, bem como a presença de Salmonella spp. no ponto de coleta ap‚s a sangria, indicando que o couro de bovinos Š fonte de introdu€ o de micro- organismos no ambiente de abate para dois frigoríficos, e que as opera€Žes de higiene e sanitiza€ o do couro de bovinos que antecedem o abate n o foram efetivas para impedir entrada destes micro-organismos no ambiente de abate. A partir das contagens das superfícies do ambiente constatou-se que as m os dos manipuladores s o um ponto importante de contamina€ o de mes‚filos aeróbios e de Enterobactericeae no frigorífico de Inspeção Estadual. Salmonella spp. foi encontrada no couro dos bovinos, nos dois Frigor‡ficos avaliados, entretanto, n o foi detectada em nenhum outro ponto de amostragem da linha de abate, do ambiente e nem nos cortes cŒrneos, demonstrando que as operações de abate foram efetivas para o controle da contaminação da carcaça e dos cortes cŒrneos, por esse micro- organismo. Os frigoríficos com diferentes n‡veis de inspeção sanitária apresentaram elevados coeficientes de correlação para a concentração de micro-organismos mesófilos aeróbios (R=0,97) e Enterobactericeae (R=0,91), e em relação à presença de Salmonella spp. n o apresentaram diferença significativa, indicando que as formas de contaminação das carcaças durante as operações de abate para estes micro-organismos s o provavelmente as mesmas.

Escherichia coli enteropatogênica atípica (EPECa) é causadora de diarréia infantil e apresenta alta heterogeneidade quanto aos fatores de virulência. O objetivo deste trabalho foi estudar o comportamento de EPECa na interação com fagócitos profissionais. Duas amostras de EPECa sorotipo O55:H7 mostraram-se capazes de reduzir a fagocitose. Os sobrenadantes dos cultivos foram submetidos a SPE e HPLC e as frações com efeito antifagocítico foram submetidas a espectrometria de massas. A fração capaz de reduzir a fagocitose de bactérias reduziu também a fagocitose de Saccharomyces cerevisiae. Além de mostrar que EPECa é capaz de induzir a antifagocitose, mostrou-se também que o fator antifagocitico é secretado, solúvel em meio aquoso, termoestável, apresenta baixo peso molecular, não é microbicida ou citotóxico e, por último, há indicativos de que possa apresentar uma região glicosídica. Estes achados sugerem que o fator antifagocítico pode, embora não sozinho, exercer um papel importante na adaptabilidade e patogenicidade das EPECa. / Atypical enteropathogenic Escherichia coli (aEPEC) causes diarrhea mainly in children and presents a high heterogeneity of virulence factors. The objective of this work was to study the behavior of aEPEC regarding its interaction with professional phagocytes. Two samples of aEPEC serotype O55:H7 were able to reduce phagocytosis, The culture supernatants were submitted to SPE and HPLC and the active fractions were tested and analyzed by mass spectrometry. The results show that the fraction with bacterial antiphagocytic activity also reduces phagocytosis of Saccharomyces cerevisiae. In addition to demonstrating that aEPEC can induce antiphagocytosis, this work shows that it is due to a secreted antiphagocytic factor that is soluble in aqueous medium, is thermo-stable, has a low molecular weight, is not bactericide or cytotoxic and, finally, possibly presents a glycosidic region. These findings suggest that the antiphagocytic factor may, though maybe not alone, play an important role in the adaptability and pathogenicity of aEPEC.

Escherichia coli possède une grande plasticité génomique comme en témoigne la diversité des souches à l’intérieur de cette espèce bactérienne. Bien que la majorité des souches soient inoffensives ou à tout le moins opportunistes, plusieurs ont acquis des facteurs de virulence spécifiques leur procurant un pouvoir pathogénique. Les souches pathogènes comme E. coli O157 :H7 sont responsables de cas de morbidité, mortalité et pertes économiques importantes dans l’industrie agro-alimentaire dans le monde entier. L’évolution bactérienne est un mécanisme continuel qui se fait via l’échange d’éléments génétiques mobiles, de mutations ponctuelles et autres réarrangements génétiques. Ces changements génétiques peuvent procurer des avantages sélectifs permettant une adaptation bactérienne rapide face aux stress et changements environnementaux et favorisant le développement de pathogènes émergents. Dans la première partie de ce projet, nous avons étudié la région intergénique mutS-rpoS, qui est une des plus grandes sources de polymorphisme chromosomique chez les entérobactéries. Notre analyse génomique comparative a permis de confirmer le polymorphisme à l’intérieur même d’un ensemble de souches Escherichia spp., Salmonella spp. et Shigella spp. De plus, nous avons pu confirmer que certains types de polymorphismes dans la région mutS-rpoS étaient fortement associés à certains types de pathogènes chez E. coli. Dans notre analyse, nous avons ressorti un groupe de gènes à l’intérieur de la région mutS-rpoS qui pourraient sevir comme marqueur chromosomique intéressant pour les E. coli extra-intestinaux (ExPEC), un groupe comprennant des souches hautement pathogènes et difficiles à définir par les tests actuelllement disponibles. Dans notre analyse bio-informatique, nous avons isolé ce groupe de gènes associé aux ExPEC et nous l’avons caractérisé in sillico. Nous avons également inclus dans l’analyse deux souches hypermutables du genre Escherichia spp. de notre collection, isolées d’animaux de ferme. L’hypermutabilité ou la capacité d’acquérir des mutations plus rapidement que la normale accélère le processus d’évolution et la capacité d’adaptation de ces souches. La région mutS-rpoS est reliée au système de réparation de l’ADN bactérien (MMRS) et pourrait être impliquée dans l’apparition du phénotype d’hypermutabilité. Durant les dernières années, de plus en plus d’espèces du genre Escherichia ont été isolées de cas cliniques d’animaux et d’humains. Ces souches atypiques ont un potentiel de virulence très élevé, des combinaisons de gènes de virulence et des variants génétiques différents des souches typiques, et certaines souches ont même évolué en tant que pathogènes. Les souches de l’espèce E. albertii ont été isolées récemment et ont un grand potentiel de virulence autant chez les humains que chez les oiseaux. Ces souches sont souvent confondues avec d’autres organismes pathogènes comme E. coli dans les tests biochimiques, et le manque de connaissances sur E. albertii rend son identification difficile. Dans la deuxième partie de ce projet, nous avons identifié des gènes spécifiques aux souches d’E. albertii ainsi que des gènes de virulence présents chez E. albertii par comparaisons génomiques, ce qui a permis de développer et optimiser un test PCR (réaction en chaîne par polymérase) visant l’identification génomique rapide et fiable d’E. albertii.

Background: Plastic stents used for the treatment of biliary obstruction will become occluded over time due to microbial colonization and formation of biofilms. Treatment of stent-associated cholangitis is often not effective because of inappropriate use of antimicrobial agents or antimicrobial resistance. We aimed to assess the current bacterial and fungal etiology of stentassociated biofilms, with particular emphasis on antimicrobial resistance. Methods: Patients with biliary strictures requiring endoscopic stent placement were prospectively enrolled. After the retrieval of stents, biofilms were disrupted by sonication, microorganisms were cultured, and isolates were identified by matrix-associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and/or biochemical typing. Finally, minimum inhibitory concentrations (MICs) were determined for various antimicrobial agents. Selected stents were further analyzed by fluorescence in situ hybridization (FISH). Results: Among 120 patients (62.5% males, median age 64 years) with biliary strictures (35% malignant, 65% benign), 113 double pigtail polyurethane and 100 straight polyethylene stents were analyzed after a median indwelling time of 63 days (range, 1–1274 days). The stent occlusion rate was 11.5%and 13%, respectively, being associated with a significantly increased risk of cholangitis (38.5% vs. 9.1%, P<0.001). Ninety-five different bacterial and 13 fungal species were detected; polymicrobial colonization predominated (95.8% vs. 4.2%, P<0.001). Enterococci (79.3%), Enterobacteriaceae (73.7%), and Candida spp. (55.9%) were the leading pathogens. Candida species were more frequent in patients previously receiving prolonged antibiotic therapy (63% vs. 46.7%, P = 0.023). Vancomycinresistant enterococci accounted for 13.7%, extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae with co-resistance to ciprofloxacin accounted for 13.9%, and azole-resistant Candida spp. accounted for 32.9% of the respective isolates. Conclusions: Enterococci and Candida species play an important role in the microbial colonization of biliary stents. Therefore, empirical antimicrobial treatment of stent-associated cholangitis should be guided toward enterococci, Enterobacteriaceae, streptococci, anaerobes, and Candida. To determine causative pathogens, an accurate microbiological analysis of the extracted stent(s) may be helpful.

Whole genome sequencing (WGS) has transformed molecular infectious diseases epidemiology in the last five years, and represents a high resolution means by which to catalogue the genetic content and variation in bacterial pathogens. This thesis utilises WGS to enhance our understanding of antimicrobial resistance in two clinically important members of the Enterobacteriaceae family of bacteria, namely Escherichia coli and Klebsiella pneumoniae. These organisms cause a range of clinical infections globally, and are increasing in incidence. The rapid emergence of multi-drug resistance in association with infections caused by them represents a major threat to the effective management of a range of clinical conditions. The reliability of sequencing and bioinformatic methods in the analysis of E. coli and K. pneumoniae sequence data is assessed in chapter 4, and provides a context for the subsequent study chapters, investigating resistance genotype prediction, outbreak epidemiology in two different contexts, and population structure of an important global drug-resistant E. coli lineage, ST131 (5-8). In these, the advantages (and limitations) of short-read, high-throughput, WGS in defining resistance gene content, associated mobile genetic elements and host bacterial strains, and the relationships between them, are discussed. The overarching conclusion is that the dynamic between all the components of the genetic hierarchy involved in the transmission of important antimicrobial resistance elements is extremely complicated, and encompasses almost every imaginable scenario. Complete/near-complete assessment of the genetic content of both chromosomal and episomal components will be a prerequisite to understanding the evolution and spread of antimicrobial resistance in these organisms.

As metalo-&#946;-lactamases (MBL) são capazes de hidrolisar os carbapenêmicos, a classe de antimicrobianos com maior potência para o tratamento de infecções graves e de maior uso clinico. Dentre as MBL, o grupo mais recentemente descrito e que apresentou rápida disseminação em todo o mundo é o da New-Delhi-Metalo- &#946;-lactamases (NDM). Nas enterobactérias, os genes que codificam essas enzimas estão mais frequentemente localizados em plasmídeos. O estudo da estabilidade de plasmídeos que albergam o gene blaNDM-1 é importante para entender a predominância de espécies que carregam esses plasmídeos, desvendar mecanismos moleculares envolvidos na sua persistência e para desenvolver novas drogas que possam diminuir a sua persistência. Estudos recentes sobre estabilidade plasmidial evidenciaram que a maprotilina é capaz de induzir perda plasmidial de até 90% em E. coli K12. Neste trabalho, foi estudado o efeito da maprotilina na indução de cura de plasmídeos, que albergam o gene blaNDM-1, em diferentes espécies da família Enterobacteriaceae. Nove isolados pertencentes a diferentes espécies foram incluídas no estudo. Os plasmídeos foram caracterizados quanto ao seu tamanho por eletroforese e por sequenciamento de DNA no sistema Illumina. A persistência plasmidial foi determinada pelo método de contagem em placa em LB ágar com e sem tratamento com maprotilina em concentrações sub-inibitórias (50mg/L). O experimento foi conduzido por 10 dias, representando aproximadamente 100 gerações. Neste estudo evidenciou-se que o grupo das enterobactérias estão envolvidas na disseminação de plasmídeos com blaNDM-1, sendo que plasmídeos do grupo IncF estão mais relacionados a essa dispersão. A maprotilina teve efeito de cura plasmidial em todos os isolados exceto em E. hormaechei \"subsp. oharae\" e C. freundii. O isolado P. rettgeri apresentou maior taxa de perda plasmidial e a análise comparativa da sequência nucleotídica do plasmídeo indicou que a presença da IS5 pode estar relacionada com a diminuição da persistência plasmidial. Diferenças na persistência plasmidial, quando tratados com maprotilina, entre E. hormaechei \"subsp. steigerwaltii\" e E. hormaechei \"subsp. oharae\" sugerem que E. hormaechei \"subsp. oharae\" pode ser um possível disseminador de plasmídeos albergando blaNDM-1, devido a processos de adaptação co-evolutivos. / Metallo- &#946;-lactamases (MBL) are able to hydrolase carbapenems, an antimicrobial class in clinical use with high potency in the treatment of severe infections. The most recently decribed group of MBL is the New-Delhi-Metallo-&#946;-lactamases (NDM). This group is mostly correlated to the spread of resistance mediated by plasmid in Enterobacteriaceae. Understanding the plasmid persistence pattern is important in order to understand the predominance of a given species related to antimicrobial resistance plasmids spread, to unveil molecular mechanisms involved in the increase of plasmid persistence and to develop new drugs which could decrease its persistence. Recent studies have associated maprotiline to a decrease in 90% of plasmid persistence in E. coli K12. In this work, we evaluated the effect of maprotiline in curing plasmids carrying blaNDM-1 in different species of Enterobacteriaceae. Nine isolates belonging to different species were evaluated. Plasmids were characterized by agarose gel electrophoresis and by DNA sequencing with Illumina platform. The plate counting method was used to determine plasmid persistence, with and without sub-inhibitory (50 mg/L) concentration of maprotiline during 10 days, representing approximately 100 generations. We found that Enterobacteriaceae are involved in the spread of NDM-1 plasmid-mediate resistance and the IncF group is the plasmid incompatibility group more frequently involved in this dissemination. Maprotiline showed a plasmid-curing effect in all isolates, except against plasmids of E. hormaechei \"subsp. oharae\" and C. freundii. The P. rettgeri isolate had the highest plasmid-curing rate. Sequencing analysis revealed an IS5 in the plasmid, which could be associated to a decrease in plasmid persistence. The difference between plasmid persistence pattern of plasmids isolated from E. hormaechei \"subsp. steigerwaltii\" and E. hormaechei \"subsp. oharae\", when treated with maprotiline, suggest that E. hormaechei \"subsp. oharae\", could be associated to the spread of plasmids carrying blaNDM-1 due to co-evolution adaptation.

A fim de pesquisar a presença de yersinia pseudotuberculosis em quadro de diarreia bovina, foram analisadas 220 amostras de fezes, 60 conteudos de intestino delgado e 56 conteudos de intestino grosso. Obteve-se isolamento positivo em 46 (21%), 9 (15%) e 5 (9%) das amostras respectivamente, totalizando 60 cepas do microrganismo. As 60 cepas de yersinia pseudotuberculosis pertenciam ao sorogrupo o iii., Apresentando identica sensibilidade aos antibioticos e quimioterapicos quando testados in vitro. Estatisticamente comprovou-se haver relação entre os isolamentos das cepas de yersinia pseudotuberculosis e os meses mais frios do ano. A cepa y. Pseudotuberculosis mostrou-se patogenica aos cobaios, quando administrada via oral. Apesar dos resultados bacteriologicos negativos, não se descartou a possibilidade do envolvimento de roedores silvestres e comensais na transmissão do microrganismo aos bovinos, podendo os proprios bovinos ou o solo, servirem como reservatorios do microrganismo. A metodologia utilizada no isolamento das cepas de y. Pseudotuberculosis possibilitou que 73,3% das mesmas fossem isoladas no cultivo primario e 26,66% apos o crioenriquecimento na temperatura de 4 GRAUS c por 7, 14 e 21 dias. / The main purposes of this research was to search for Yersinia pseudotuberculosis in faecal samples from bovine with diarrhea, from farms in the State of Paraná. We have analyzed 220 faecal samples, 60 samples from small intestine contents and 56 samples from large intestine contents. Yersinia pseudotuberculosis isolation was positive in 46 (21%), 9 (15%) and 5 (9%), respectively, totalizing 60 strains of the microrganism. The 60 strains of Yersinia pseudotuberculosis belong to serogroup 0 III, and they shown identical sensibility to antibiotics and other drugs, when tested in vitro. Through the statistical methods, X2 test, we found a positive correlation between Yersinia pseudotuberculosis isolation and the winter season. To establish the morbidity and mortality rates, cattle population was separated into three age related categories, wich are: calfs, yearlings and adults. In 1987 and 1988, the morbidity rates were 0%, 10,3% and 6,7%; 0%, 13,4% and 11,7%, respectively. In relation to mortality rates, they were 0%, 1,0% and 2,6% in 1987, and 0%, 2,1% and 2,6% in 1988. The strains of Yersinia pseudotuberculosis placed on serogroup 0 III, were pathogenic to guinea pigs, when giver per-os. We didn\'t get any isolation of Yersinia pseudotuberculosis from wild rodents and others, but we still think that may be incriminated in the transmission of the microrganism to bovines, although the bovines as well as the soil, may function as reservoires of the bacteria. Isolation of Yersinia pseudotuberculosis in primary cultures was possible in 73,33% although 26,66% of the isolations were successfull only after cold-temperature enrichment, with incubation at 4 C for 7, 14 an 21 days.