Project description:The present study examines changes in global gene expression patterns and in virulence factor-associated genes in an extended spectrum beta-lactamase (ESBL)-producing UPEC (ESBL019) during the morphologic transitions induced by an ineffective antibiotic and in the presence of human primary bladder epithelial cells. The morphological shifts induced by ineffective antibiotics are associated with significant transcriptional virulence alterations in ESBL-producing UPEC, which may affect survival and persistence in the urinary tract.
Project description:Avian Pathogenic Escherichia coli (APEC) are a group of extra-intestinal E. coli that infect poultry, and are able to cause a variety of diseases, systemic or localized, collectively designated as colibacillosis. Colibacillosis is the most common bacterial illness in poultry production, resulting in significant economic losses world-wide. Despite of its importance, pathogenicity mechanisms of APEC strains remain not completelly elucidated and available vaccines are not fully effectives. In order to better understand which genes could be related to pathogenicity in different APEC isolated, a microarray analyses of two APEC strains representing: Swollen Head Syndrome and Omphalitis was carried out.
Project description:Avian Pathogenic Escherichia coli (APEC) are a group of extra-intestinal E. coli that infect poultry, and are able to cause a variety of diseases, systemic or localized, collectively designated as colibacillosis. Colibacillosis is the most common bacterial illness in poultry production, resulting in significant economic losses world-wide. Despite of its importance, pathogenicity mechanisms of APEC strains remain not completelly elucidated and available vaccines are not fully effectives. In order to better understand which genes could be related to pathogenicity in different APEC isolated, a microarray analyses of two APEC strains representing: Swollen Head Syndrome and Omphalitis was carried out. We used the microarray methodology to evaluate the expression profile of two different APEC strains
Project description:The emergence of colistin resistance in carbapenem-resistant and extended-spectrum ß-lactamase (ESBL)-producing bacteria is a significant threat to human health, and new treatment strategies are urgently required. Here we investigated the ability of the safe-for-human use ionophore PBT2 to restore antibiotic sensitivity in several polymyxin-resistant, ESBL-producing, carbapenem resistant Gram-negative human pathogens. PBT2 was observed to resensitize Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa to last-resort polymyxin class antibiotics, including a ‘next generation’ polymyxin derivative, FADDI-287. To gain additional insight into the potential mechanism of action of PBT2, we analyzed the transcriptome of K. pneumoniae and E. coli in the presence of sub-inhibitory concentrations of PBT2. Treatment with PBT2 was associated with multiple stress responses in both K. pneumoniae and E. coli. Significant changes in the transcription of transition metal ion homeostasis genes were observed in both strains.
Project description:Avian pathogenic Escherichia coli strains frequently cause extra-intestinal infections and are responsible for significant economic losses in the poultry industry worldwide. APEC isolates are closely related to human extraintestinal pathogenic E.coli strains and may also act as pathogens for humans. In this work, three type VI secretion systems were deleted to analyze which pathogenicity characteristics would change in the mutants, compared to wild type strain (SEPT 362).