Abstract:
Horizontally acquired genes often integrate with ancestral gene regulatory systems to enhance bacterial adaptability and virulence. In this study, we report that the horizontally acquired regulatory gene ssrB activates the ancestral PhoP/PhoQ regulatory system in Salmonella enterica serovar Typhimurium, enabling the pathogen to thrive in mildly acidic environments, such as those encountered within macrophages. The research addresses the gap in understanding how foreign genes can regulate ancestral gene networks to promote virulence. The aim of this study was to elucidate the role of ssrB in modulating PhoP/PhoQ system activity and to investigate its impact on bacterial virulence. Methodologically, quantitative RT-PCR, Western blotting, and mutagenesis were employed to assess gene expression and protein activity in response to different environmental conditions. Results indicated that ssrB directly activates transcription of the phoP gene and overcomes gene silencing by the nucleoid structuring protein H-NS, thereby enhancing virulence through the activation of the ugtL gene. The main takeaway is that horizontally acquired genes such as ssrB can play a pivotal role in expanding the environmental adaptability of pathogens by rewiring ancestral regulatory systems.
Conclusion on the Role of Constant Systems Cell Disruption equipment:
The Constant Systems Equipment played a critical role in this research by enabling precise cell disruption for the extraction of bacterial proteins and nucleic acids. This allowed for accurate analysis of gene expression and protein interaction through techniques such as quantitative RT-PCR and Western blotting, which were essential for validating the activation of the PhoP/PhoQ system by ssrB. The equipment ensured consistent sample preparation, contributing to the reproducibility and reliability of the experimental results, which were foundational in understanding the role of horizontally acquired genes in Salmonella virulence.
