Helen Tran Rose Hills
A Genetic Analysis of Bacterial Proteins Involved in ATP Secretion
To infect host cells, Salmonella uses its Type III Secretion System to inject virulence factors necessary for pathogenesis. Understanding the movement of ATP in Salmonella will help us understand how this bacterial pathogen regulates its secretion of virulence factors and its communication with host cells. This summer, I am performing a genetic analysis on bacterial proteins involved in ATP secretion of Salmonella. After screening a panel of E. coli mutants for defects in ATP secretion, it was concluded that mutants were defective in ATP secretion when two subunits of an enzyme, cytochrome bo oxidase, were deleted. These subunits are coded by cyo A and cyo B genes. E. coli is a gram-negative enteric bacterium that is closely related to Salmonella, so I will make the same deletion mutants of the two genes in Salmonella typhimurium and Salmonella enteritidis to determine if the same enzyme is responsible for ATP secretion. I will then measure the ATP secretion of each of the mutants and finally complement them with copies of their respective wild type genes. If ATP secretion is restored, it can be concluded that cytochrome bo oxidase is necessary for ATP secretion in both strains of Salmonella.