Role of the cadAB operon in the Egg Resistance of Salmonella

Raul Clavijo : Molecular and Cell Biology

Mentor: Sangwei Lu, Public Health

The basic purpose of Raul’s study, which will form the basis for his senior honors thesis in Molecular and Cell Biology, is to understand a characteristic of Salmonella enteritidis (S. enteritidis) that allows it to be the only bacterium to contaminate chicken eggs routinely. The specific objective is to determine the role of a particular set of genes, found in the cadAB operon, in conferring egg albumen/white resistance to S. enteritidis. Preliminary data has shown that a mutant S. enteritidis, with an interruption that disables the cadAB operon, is more susceptible to being eradicated in egg albumen than the wild type S. enteritidis. The cadAB operon’s function is to code for proteins that are involved in lysine-cadaverine transport and regulation of outer membrane permeability under certain conditions. Raul will determine this operon’s function when S. Enteritidis is exposed to egg albumen and its role in allowing the bacterium to survive the antimicrobial egg albumen.