Project description:au07-07_salmonella - infection with Salmonella or Pseudomonas or E. coli. Identification of genes involved in early Arabidopsis response to pathogenic and non-pathogenic bacteria. Arabidopsis thaliana Col-0 seedlings were infected for 2 hours with a) Salmonella typhimurium strain 14028s, b) Pseudomonas syringae DC3000 or c) Escherichia coli DH5A Keywords: treated vs untreated comparison
Project description:OmpR is a DNA binding protein belonging to the OmpR/EnvZ two component system. This system is known to sense changes in osmolarity in Escherichia coli. Recently, OmpR in Salmonella enterica serovar Typhimurium was found to be activated by acidic pH and DNA relaxation. In this study, ChIP-on-chip was employed to ascertain the genome-wide distribution of OmpR in Salmonella Typhimurium and Escherichia coli in acidic and neutral pH. In addition we investigated the affect of DNA relaxation on OmpR binding in Salmonella Typhimurium.
Project description:Avian pathogenic Escherichia coli (APEC) is a subset of extraintestinal pathogenic E. coli that causes detrimental losses to the poultry industry. Vaccines to reduce APEC in chickens have been partially successful, but many lack protection against multiple serotypes of APEC. Recombinant attenuated Salmonella vaccine (RASV) strains have been used to induce immunity against Salmonella in production chickens and can be modified to deliver foreign antigens as well. This study evaluated the transcriptome of chicken spleens and assessed prevention of APEC infection following vaccination with RASV strains, including a RASV carrying an E. coli antigen. Four-day-old White Leghorn chicks were orally vaccinated with RASV c8025(pYA3337) carrying an empty plasmid, c8025(pYA4428) carrying genes for E. coli common pilus (ECP), a combination of RASVs c8025(pYA3337) and c8025(pYA4428), or PBS (unvaccinated). To assess the host response to vaccination, antibody titers were measured by ELISA and spleen samples (n = 5) were collected from combination vaccinated and unvaccinated groups of four-week-old chickens for RNA sequencing. Five-week old chickens were challenged via air sac with APEC strains APEC-O2 and c7122 (O78). Blood was obtained 24 hours post-challenge, heart, liver, lung, and spleen were collected 48 hours post-challenge for enumeration of E. coli, and gross colibacillosis lesions were scored at necropsy. Chickens vaccinated with RASV strains elicited anti-E. coli EcpA, as well as cross reactive anti-E. coli IutA and IroN IgY antibodies. IgA results. In some organs, bacterial loads and lesions scores were numerically reduced, but no significant differences were detected for vaccinated compared to unvaccinated chickens. Transcriptome results. This data indicates that RASVs could be used to stimulate the immune system and is an initial step toward developing improved therapeutics to combat APEC infections in chickens.
Project description:au07-07_salmonella - infection with Salmonella or Pseudomonas or E. coli. Identification of genes involved in early Arabidopsis response to pathogenic and non-pathogenic bacteria. Arabidopsis thaliana Col-0 seedlings were infected for 2 hours with a) Salmonella typhimurium strain 14028s, b) Pseudomonas syringae DC3000 or c) Escherichia coli DH5A Keywords: treated vs untreated comparison 6 dye-swap - CATMA arrays
Project description:The non-typhoidal Salmonella enterica serotype Heidelberg is a major foodborne pathogen primarily transmitted to humans through contaminated poultry products. Current control measures emphasize novel approaches to mitigate Salmonella Heidelberg colonization in poultry and the contamination of poultry products, thereby reducing its transmission to humans. This study highlight that commensal E. coli 47-1826 can potentially be used to control of S. Heidelberg 18-9079 in poultry
Project description:Salmonella is an important enteric pathogen that causes a spectrum of diseases varying from mild gastroenteritis to life threatening typhoid fever. Salmonella does not have lac operon. However, E. Coli, Salmonella’s close relative, has lac operon. Being an enteric pathogen like E. coli, Salmonella will also benefit from lac operon. Then, why Salmonella has lost lac operon?. To address this question, lacI, an important component of lac operon was expressed in Salmonella via pTrc99A plasmid. As a control, pTrc99A without lacI was also expressed in Salmonella. The effect of LacI on the transcription profile of Salmonella was analyzed using microarray technique.