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<p>Goal 1 - Determine if the genes allow for a greater percentage of persistent cells that are resistance to standard treatments used to sanitize for bacteria. The himA himB system was the first confirmed molecular system allowing the formation of persister cells. This system in Salmonella and other bacteria is homologous, but also shows some interesting differences from the original system that necessitates further investigation. </p><p>Goal 2 - Determine if the persistence genes also alter the ability of the genetic element to move between strains of Salmonella and potentially other strains of pathogenic bacteria. Interestingly, the persistence genes are in a region of the genetic element that is typically involved in controlling movement of the element. Genetic elements are sensitive to the metabolic state of the cell. It is essential to know if activation of the persister system activates spread of the element.
Food poisoning is a major food safety issue in New York State. Salmonellosis is the most frequent type of food poisoning. For the first time, we have found that a molecular system that allows bacteria to form a semi-dormant state or "persistent state" can be spread on mobile "jumping genes" called transposons. This system was found in many types of Salmonella associated with serious food poisoning outbreaks including, Salmonella Heidelberg, Montevideo, Tennessee and Senftenberg. One of the reasons that this is a serious concern is that protocols set up to sanitize and control for growth of bacteria are established with strains of bacteria that may not have this persistence system. It is important to know if the genes that allow persistence are allowing pathogens to subvert sanitation procedures. However, its spread on mobile elements is consistent with an important role for this genetic element and the genes it encodes in food poisoning. The persistence genes are encoded on a newly appreciated member of a group of transposons that is very efficiently transmitted between bacteria called a heteromeric transposase element. In our work we will characterize the persistence genes to determine how they change the ability of the bacterial strain to withstand sanitary treatments, treatments with biocides, and treatments with antibiotics. We will also determine if this putative "persistence" system affects how the element itself spreads between bacteria. Ultimately, these findings may lead to new sanitation and monitoring procedures to adequately protect the New York State food production system.