Comparative gene expression analysis of Salmonella Typhimurium DT104 in ground chicken extract and brain heart infusion broth

Authors: Liu, Yanhong; ZHANG, FANGYUAN - Villanova University; HAWKINS, J - University Of Maryland Eastern Shore (UMES); ELDER, JAKE - Former ARS Employee; BARANZONI, GIAN - Former ARS Employee; HUANG, ZUYI - Collaborator; FRATAMICO, PINA - Retired ARS Employee; PARVEEN, S - University Of Maryland Eastern Shore (UMES)

Submitted to: Microorganisms
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2024
Publication Date: 7/18/2024
Citation: Liu, Y., Zhang, F., Hawkins, J.L., Elder, J., Baranzoni, G.M., Huang, Z., Fratamico, P., Parveen, S. 2024. Comparative gene expression analysis of Salmonella Typhimurium DT104 in ground chicken extract and brain heart infusion broth. Microorganisms. 12:1461. https://doi.org/10.3390/microorganisms12071461.
DOI: https://doi.org/10.3390/microorganisms12071461

Interpretive Summary: Salmonella is an important foodborne pathogen that causes a serious disease called salmonellosis in humans. Since this pathogen often causes outbreaks associated with poultry and poultry products, there is a need to study how Salmonella grows and survives in chicken meat. RNA-Seq technology is a powerful tool that can be used to study the expression of all of the genes possessed by a bacterium under different conditions. To study which genes are utilized when Salmonella is exposed to chicken meat, RNA-Seq was used to study the gene expression patterns of this bacterium in ground chicken extract. A number of genes that allow Salmonella to utilize the components of chicken meat and to grow and survive were identified. Knowledge of these genes will allow the design of strategies targeting these genes to control the growth of Salmonella in poultry.

Technical Abstract: Salmonella enterica Typhimurium DT104 (DT104) is an important foodborne pathogen that is associated with poultry and poultry products. Currently, there is limited information on the underlying molecular mechanisms that allows DT104 to survive and propagate in the poultry processing environment. The current study assessed global gene expression of DT104 in ground chicken extract (GCE) compared to brain heart infusion (BHI) medium using RNA-Seq technology. DT104 was grown to early stationary phase (ESP) and then inoculated into GCE or BHI. The sub-cultured DT104 were then grown to log phase before RNA was extracted and transcripts were quantified via RNA-Seq. Gene expression for DT104 grown in GCE was then compared to DT104 grown in BHI for samples grown to ESP. Growth in GCE resulted in the up-regulated expression of genes related to translation, carnitine metabolism, and cobalamin biosynthesis. In particular, the presence of carnitine in relatively high concentration in chicken meat may allow Salmonella to utilize this compound as a carbon and nitrogen source, thus enhancing its growth and survival. This study demonstrates that RNA-Seq data can provide a comprehensive analysis of DT104 expression in a model for the poultry processing environment. This study also provides additional evidence for the importance of metabolic fitness in the ability of S. enterica to successfully adapt to and occupy niches outside of its host.