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Guinote I.B.,New University of Lisbon | Guinote I.B.,Laboratorio Nacional Of Investigacao Veterinaria Inrb | Moreira R.N.,New University of Lisbon | Freire P.,New University of Lisbon | And 2 more authors.
Journal of Microbiology and Biotechnology | Year: 2012

BolA protein homologs are widely distributed in nature. In this report, we have studied for the first time YrbA, the only BolA homolog present in Escherichia coli, which we have renamed ibaG. We have constructed single and multiple ibaG mutants, and overexpressed ibaG in wildtype strains, in order to characterize this gene. The ibaG phenotypes are different from the bolA-associated round morphologies or growth profiles. Interestingly, ibaG and bolA single- and double-deletion mutants grow faster and have higher viabilities in rich media, whereas the overexpressed strains are significantly growth impaired. However, the mutant strains have lower viabilities than the wild type in the late stationary phase, indicating that both bolA and ibaG are important for survival in difficult growth conditions. bolA, as a transcription factor, binds to some promoters, but ibaG does not interact with the same DNA regions. We have determined that ibaG is transcribed in an operon with the murA gene, involved in the synthesis of peptidoglycan precursors. ibaG was also seen to change its mRNA expression pattern in response to acidic stress. ibaG may thus represent a new gene involved in cell resistance against acid stress. © The Korean Society for Microbiology and Biotechnology.


Vieira-Pinto M.,University of Trás os Montes e Alto Douro | Alberto J.,University of Trás os Montes e Alto Douro | Aranha J.,University of Trás os Montes e Alto Douro | Serejo J.,Camara Municipal de Idanha a Nova | And 3 more authors.
European Journal of Wildlife Research | Year: 2011

Bovine tuberculosis (bTB), widely considered a disease of livestock, can also affect large game species despite their poorly understood role in the epidemiology of the endemic state of the disease. The Idanha-a-Nova County, situated in the eastern region of central Portugal, is one of the most important regions for large game hunting activity. In order to investigate the role of large game and the presence of bTB in Idanha-a-Nova, 132 wild boar (Sus scrofa) and 339 red deer (Cervus elaphus) were inspected for bTB-compatible lesions (bTBCL) during the 2008-2009 hunting season. Tissue samples with bTBCL were collected and processed for bacteriological confirmation and spoligotyping of Mycobacterium bovis isolates. In wild boar, bTB lesions were single, mostly calcified (21/29, 72. 4%) and situated in the mandibular lymph nodes. Lesions were more severe and largely non-calcified (36/40, 90%) in red deer. Wild boar presented a consistently higher bTB infection rate than the red deer; however, the difference was only significant in the southern B area. This area was significantly affected by bTB for both animal species (up to 72. 7% in wild boar and 34. 8% in red deer) and requires the urgent implementation of intervention measures to contain the disease. Wild boar may assume an important role in the emergence of new disease foci in distant areas that infected red deer cannot reach. Spoligotyping of M. bovis isolates grouped the strains into three clusters, revealing patterns common to wild boar, red deer, and also to local cattle, indicating possible transmission among different animal species. © 2011 Springer-Verlag.


Guinote I.B.,New University of Lisbon | Matos R.G.,New University of Lisbon | Freire P.,New University of Lisbon | Freire P.,Laboratorio Nacional Of Investigacao Veterinaria Inrb | Arraiano C.M.,New University of Lisbon
Journal of Microbiology and Biotechnology | Year: 2011

The gene bolA was discovered in the 80's, but unraveling its function in the cell has proven to be a complex task. The BolA protein has pleiotropic effects over cell physiology, altering growth and morphology, inducing biofilm formation, and regulating the balance of several membrane proteins. Recently, BolA was shown to be a transcription factor by repressing the expression of the mreB gene. The present report shows that BolA is a transcriptional regulator of the dacA and dacC genes, thus regulating both DD-carboxypeptidases PBP5 and PBP6 and thereby demonstrating the versatility of BolA as a cellular regulator. In this work, we also demonstrate that reduction of cell growth and survival can be connected to the overexpression of the bolA gene in different E. coli backgrounds, particularly in the exponential growth phase. The most interesting finding is that overproduction of BolA affects bacterial growth differently depending on whether the cells were inoculated directly from a plate culture or from an overnight batch culture. This strengthens the idea that BolA can be engaged in the coordination of genes that adapt the cell physiology in order to enhance cell adaptation and survival under stress conditions. © The Korean Soceity for Microbiology and Biotechnology.

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