Project description:Pseudomonas aeruginosa is one of the most frequent pathogen dominant in complicated urinary tract infections (UTI). To unravel the adaptation strategies of P. aeruginosa to the conditions in the urinary tract and to define the underlying regulatory network an artificial growth system mimicking the conditions in the urinary tract was established. Transcriptome analyses were used to investigate the physiological status of P. aeruginosa under this conditions.
Project description:Proteus mirabilis is a leading cause of catheter-associated urinary tract infections (UTIs) and urolithiasis. The transcriptional regulator MrpJ inversely modulates two critical aspects of P. mirabilis UTI progression: fimbria-mediated attachment to the urinary tract, and flagella-mediated motility. Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) was used for the first time in a CAUTI pathogen to probe for in vivo direct targets of MrpJ. ChIP-seq revealed 81 78 direct MrpJ targets, including genes for motility, fimbriae and a type VI secretion system (T6SS), and the putative MrpJ binding sequence ACnCnnnnnnnGnGT.
Project description:Pseudomonas aeruginosa is one of the most frequent pathogen dominant in complicated urinary tract infections (UTI). To unravel the adaptation strategies of P. aeruginosa to the conditions in the urinary tract and to define the underlying regulatory network an artificial growth system mimicking the conditions in the urinary tract was established. Transcriptome analyses were used to investigate the physiological status of P. aeruginosa under this conditions. We performed comparisons to identify genes induced under artificial urinary tract conditions to unravel the adaptive strategies and the underlying regulatory network used by Pseudomonas aeruginosa during urinary tract infections using Affimetrix GeneChips. Pseudomonas aeruginosa wild type strain PAO1 was grown in an artificial in vitro growth system mimicking the conditions in the urinary tract. Therefore, biofilms were grown on the surface of membrane filters placed on agar plates at 37 °C up to the late logarithmic state under aerobic and anaerobic conditions (incubated in an anaerobic beanch). An artificial urine medium (AUM) simulating the averaged urine of an human adult was used as nutrient souce. 10-fold diluted Luria Bertani (LB)-medium was used as reference medium. For growth under oxygen depletion the media were supplemented with 50 mM KNO3 to sustain anaerobic respiration. The biofilms were harveted at this time points and resuspsended in 0.9% (w/v) NaCl. The OD578 of biofilm suspension was 0.8 for all tested conditions. First comparison: Identification of genes induced or repressed under aerobic conditions in the P. aeruginosa wild type PAO1. Here we compared the transcriptome profile of P. aeruginosa PAO1 grown aerobically for 18 h to the late logarithmic phase in biofilms on AUM with the transcriptome profile of the PAO1 strain, which was grown aerobically for 18 h to the late logarithmic phase in biofilms on 10-fold diluted LB. Second comparison: Identification of genes induced or repressed under anaerobic conditions in the P. aeruginosa wild type PAO1. Here we compared the transcriptome profile of P. aeruginosa PAO1 grown anaerobically for 2 days up to the late logarithmic phase in biofilms on AUM supplemented with 50 mM nitrate with the transcriptome profile of the PAO1 strain, which was grown anaerobically for 2 days up to the late logarithmic phase in biofilms on 10-fold diluted LB supplemented with 50 mM nitrate.
Project description:Urinary tract infections (UTIs) are the second most common infections encountered in the pediatric population, second only to respiratory tract infections. UTIs are also a major cause of morbidity and mortality. UTIs can often ascend causing infection in the upper urinary tract or even progress to bacteremia or urosepsis. Urosepsis accounts for 10-30% of septic shock cases and Uropathogenic E.coli (UPEC) is responsible for almost 75% of cases. Therefore, increased understanding of the effects of urosepsis at the cellular and organ specific level will provide the foundation for improvements in clinical care.