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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, RESULTS. Meshes: Cell Communication, Cell Cycle, Colony Count, Microbial, Culture Media, Hot Temperature, Salmonella typhimurium, Time Factors.
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Do cell-cell interactions influence resistance and survival of Salmonella serotype Typhimurium to environmental stress? Context: The aim of this work was to study the effects of prolonged nutrient stress on survival, cell interactions and resistance to inimical processes in Salmonella serotype Typhimurium. Salmonella Typhimurium cells were subjected to prolonged incubation in the stationary phase of growth and the properties of starved cells (old) were investigated with reference to those of exponentially-growing cells (young). Competition experiments between old and young cells revealed cell-cell interactions that influenced stationary phase survival and response of the bacterium to heat stress. During prolonged incubation of cells, cycles of resistance and sensitivity to heat stress were identified. Competition experiments between old and young cells revealed that the resistance of young cells to heat increased to levels more like those of stationary phase cells than growing cells. The presence of old cells influenced the phenotype of young cells, possibly by means of cell-cell interactions. There was no evidence for the involvement of any extracellularly-produced factors in this phenomenon, but a requirement that the old competitor cells be viable could be demonstrated.
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It is proposed that the complex interactions within stationary phase cultures of Salm. Typhimurium may be due to cycles of mutation in concert with an as yet undefined interaction between old cells and growing ones. Final Decision: yes