Project description:Purpose: Searching for sRNAs in Salmonella pullorum by RNA sequencing and exploring their functions.Methods: High-throughput sequencing of RNA extracted from Salmonella pullorum under normal growth conditions to detect newly discovered sRNAs, followed by experiments to verify their functions.Results: The proportion of Clean Reads of this sequencing was >65%, and the base Q30s were all above 85%, indicating that the sequencing quality is good and can be used for subsequent analysis. The sRNAscanner software predicted that 148 new sRNAs might exist on the reference genome of Salmonella fowl dysentery, and the reads obtained from sequencing were compared to the genome, and it was found that 110 out of the 148 newly predicted sRNAs could be detected.Conclusions: sRNAs are widely found in bacteria and are involved in many physiological processes. In this study, we detected new sRNAs in Salmonella pullorum by RNA-seq, which lays the foundation for the subsequent investigation of the regulatory functions of sRNAs in bacteria.
Project description:Salmonella Heidelberg is currently the 9th common serovar and has more than twice the average incidence of blood infections in Salmonella. A recent Salmonella Heidelberg outbreak in chicken infected 634 people during 2013-2014, with a hospitalization rate of 38% and an invasive illness rate of 15%. While the company’s history suggested longstanding sanitation issues, the strains’ characteristics which may have contributed to the outbreak are unknown. We hypothesized that the outbreak strains of S. Heidelberg might possess enhanced stress tolerance or virulence capabilities. Consequently, we obtained nine food isolates collected during the outbreak investigation and several reference isolates and tested their tolerance to processing stresses, their ability to form biofilms, and their invasiveness in vitro. We further performed RNA-sequencing on three isolates with varying heat tolerance to determine the mechanism behind our isolates’ enhanced heat tolerance. Ultimately, we determined that (i) many Salmonella Heidelberg isolates associated with a foodborne outbreak have enhanced heat resistance (ii) Salmonella Heidelberg outbreak isolates have enhanced biofilm-forming ability under stressful conditions, compared to the reference strain (iii) exposure to heat stress may also increase Salmonella Heidelberg isolates’ antibiotic resistance and virulence capabilities and (iv) Salmonella Heidelberg outbreak-associated isolates are primed to better survive stress and cause illness. This data helps explain the severity and scope of the outbreak these isolates are associated with and can be used to inform regulatory decisions on Salmonella in poultry and to develop assays to screen isolates for stress tolerance and likelihood of causing severe illness.
Project description:Salmonella enterica Pullorum（S. Pullorum） is one of the most important pathogens in poultry. A better understanding of the immune response and molecular modulation resulting from infection by S. Pullorum will facilitates the control of this pathogen. In this study, we determined the relationships among identified differential expressed genes (DEGs) and pathways via deeply mining microarray data from Guangxi Huang Chicken challenged with S. Pullorum.
Project description:High-throughput CRISPR typing must not replace traditional phage typing for epidemiological surveillance and outbreak investigation of Salmonella Typhimurium
