In Situ, Label-Free Study Of The Correlation Between Mg2d Uptake Proteins And Motility Of Salmonella Typhimurium Using Time-Resolved Dynamic Laser Speckle Imaging

Salmonella Typhimurium is one of the leading causes of human and animal salmonellosis, and the increasing rate of antibiotic resistance in this pathogen poses a significant global concern. Understanding the basic mechanisms that allow Salmonella to survive and adapt to its environment is vital to understanding the best ways to eliminate it. Through various studies, there has been a common thread between the increased virulence and increase in magnesium transport proteins, namely CorA, MgtA, and MgtB, in the bacteria's cellular membrane. Here, we use dynamic laser speckle imaging (DLSI) to study how motion and Mg2+ transport mechanisms are correlated with response of Salmonella to antibiotics, specifically ciprofloxacin. The strains of Salomella Typhimurium that are used include TL1, TL4295, TL4501, TL4503, TL4906, TL5354, TL5777, and TL4295—all of which contain combinations of the inclusion and exclusion of the Mg2+ transport proteins CorA, MgtA, and MgtB. Studying these different strains and comparing to the Wild Type strain, TL1, will give significant insight into how magnesium affects the movement of Salmonella cells exposed to the antibiotic. In addition to antibiotics, studies will be extended to heat shock, which is the most common method used in food safety. Because this has not been previously studied, the motion of these varieties could provide new insight and introduce a new approach to improve healthcare and food safety.