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Previous issue date: 2011 / As doenças transmitidas por alimentos (DTA), causadas por micro-organismos, representam um importante problema de saúde pública, com ênfase especial aos países em desenvolvimento. O queijo Minas Frescal é um produto tipicamente nacional, de tecnologia simples e de larga aceitação no país, o que faz de sua produção uma importante atividade econômica. Diversos surtos de DTA, associados ao consumo de queijos contaminados têm sido relatados. A Escherichia coli (E. coli), é o bacilo anaeróbio facultativo predominante da microbiota intestinal de humanos e animais, encontrando-se amplamente distribuída no ambiente. De modo geral, essa bactéria é considerada um comensal inofensivo, no entanto, diversas cepas apresentam potencial patogênico. Ao menos seis categorias são descritas: E. coli enteropatogênica (EPEC), E. coli enterotoxigênica (ETEC), E. coli produtora de toxina Shiga (STEC), E. coli enteroagregativa (EAEC), E. coli enteroinvasivara (EIEC) e E. coli produtora de aderência difusa (DAEC). Este estudo teve como objetivo isolar, avaliar a susceptibilidade antimicrobiana e caracterizar genotipicamente, as cepas patogênicas de E. coli, isoladas de queijo Minas Frescal comercializados na região metropolitana do Rio de Janeiro. Foram analisadas trinta amostras, sendo 22 com algum selo de Serviço de Inspeção e 8 de origem artesanal. Cinco cepas EPEC (MTD1, MTD2, MTD3, MTD4 e MTD5) foram isoladas, caracterizadas genotipicamente e confirmadas pela amplificação do gene eae. A avaliação da susceptibilidade antimicrobiana revelou 40% de resistência a ampicilina e 40% de perfil de resistência intermediária a associação ampicilina-sulbactam. As cepas isoladas não revelaram a presença de enzimas β-lactamase de amplo espectro (ESBL)... / Foodborne Diseases, caused by microrganisms, represents a problem of public health, especially on developing countries. The Minas soft cheese is a national product, with simple technology and high acceptance in the country, making its production an important economic activity . Several outbreaks of foodborne diseases, associated with the consumption of contaminated cheese have been reported. Escherichia coli (E. coli) is the predominant anaerobic facultative bacillus of enteric microbiota from humans and animals and is widely distributed in the environment. Overall, E. coli is a harmless commensal, however, some strains have a pathogenic potential. At least six groups are described: enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), Shiga toxin-producing E. coli (STEC), enteroaggregative E. coli (EAEC), enteroinvasive E. coli (EIEC) and producing diffuse adherent E. coli (DAEC). This study aimed to isolate, evaluate the antimicrobial susceptibility and genotypically characterize pathogenic strains of E. coli isolated from soft cheese commercialized in Rio de Janeiro. Thirty samples were analyzed, 22 with Inspection Service and 8 of handmade origin. Five EPEC strains (MTD1, MTD2, MTD3, and MTD4 MTD5) were identified, genotypically characterized and confirmed by eae gene amplification. The assessment of antimicrobial susceptibility revealed 40% resistance to ampicillin and 40% with intermediate resistance to ampicillin-sulbactam combination. The isolates were negative for broad-spectrum β-lactamase enzymes (ESBL). The gene eae of pathogenic strains were sequenced and deposited in GenBank. To perform the genetic tipification of isolates by Multilocus Sequence Typing (MLST) analysis the adk, fumC, gyrB, icd, mdh, purA and recA genes were sequenced. Three strains (MTD1, MTD2 e MTD3) were characterized with two new ST (ST-2134 and ST-2147) not associated to any known clonal complex. One strain was classified as ST-48 belonging to clonal complex 10 and one strain was classified as ST-1717, with no clonal complex association. The occurrence of pathogenic E. coli strains belonging to clonal complex 10 is described in domestic animals, humans and foods. This is the first study to analyse pathogenic E. coli strains isolated from food, by MLST, in Brazil, and the first result included in the E. coli MLST database of E.coli isolated from Minas soft cheese. These findings may represent a warning to health authorities, since this is a food product ready for consumption, posing a health risk to the population.
| Identifer | oai:union.ndltd.org:IBICT/oai:www.arca.fiocruz.br:icict/8328 |
| Date | January 2011 |
| Creators | Dias, Mariana Tavares |
| Contributors | Oliveira, Luiz Antonio Trindade de, Tancredi, Rinaldi Carolini Philippo, Almeida, Antonio Eugênio Castro Cardoso de, Capasso, Ivano Raffaele Victorio de Filippis, Marin, Victor Augustus, Capasso, Ivano Raffaele Victorio de Filippis, Marin, Victor Augustus |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Source | reponame:Repositório Institucional da FIOCRUZ, instname:Fundação Oswaldo Cruz, instacron:FIOCRUZ |
| Rights | info:eu-repo/semantics/openAccess |
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