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| Author(s): |
Tamires Fernanda Vilas Boas Cordeiro
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2014-03-14 |
| Examining board members: |
Marcelo Brocchi;
Cristina Elisa Alvarez Martinez;
Regina Lucia Baldini
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| Advisor: | Marcelo Brocchi |
| Abstract | |
Salmonella enterica is one of the most prevalent foodborne pathogens. It is a gram- negative bacterium, belonging to the Enterobacteriaceae family, intracellular facultative, non-spore forming, anaerobic facultative, capable of infecting animals, including man. It¿s usually acquired through foods contaminated with such microorganism and can cause gastroenteritis and bacteremia in humans. This study proposes the construction of mutant strains of S. enterica Typhimurium for genes encoding nucleoid-associated proteins (NAPs). These proteins help on folding of DNA, allowing the bacterial chromosome to be compressed, also influencing the transcriptional regulation of genes, especially those that respond to environmental changes. The NAPs are numerous and the study of this group is very important, because several explanations still have to be made regarding most of these proteins. Recent data from our research group has shown that null mutants of S. enterica Typhimurium for genes encoding NAPs are attenuated for virulence and capable of inducing protection in a murine model of infection. These results demonstrate the important role of these proteins in bacterial virulence. Thus, the present study aims at the construction of null mutants for two genes encoding NAPs (stpA and ybaB) in S. enterica Typhimurium and at the evaluation of the phenotype of these mutants. There are no data in the literature about the role of such NAPs regarding bacterial virulence. For the YbaB, there are no data in the literature about the role of this NAP in enterobacteria. The ? Red recombination system was used to obtain the mutants. For observation of the phenotype of such strains, in vitro and in vivo experiments were performed. The results obtained in in vitro experiments showed interesting phenotypes of mutant strains compared to their wild-type strains. In the case of ?stpA mutation, increased cell survival was observed on certain stress situations compared to the wild-type strain. For the ?ybaB mutation, our studies suggest that deletion of this gene had effect on motility of mutant cells. For virulence of the constructed mutants, these mutations did not affect the pathogenicity of S. enterica considerably. Thus, the mutant strains obtained in this study have no potential to be applied as vaccines, but this work provides prospects for future studies on the biological role of YbaB in S. enterica (AU) | |
| FAPESP's process: | 12/05308-0 - Construction of mutant strains of Salmonella enterica Typhimurium for genes encoding DNA-binding proteins: evaluation of phenotypic characteristics |
| Grantee: | Tamires Fernanda Vilas Boas Cordeiro |
| Support Opportunities: | Scholarships in Brazil - Master |