Microbiology in Depth: Microbial Stress Response


Our first Microbiology In Depth program is Microbial Stress Response. Microbes are found in diverse environments, including on and inside the human body, in food and in soil. While they may not immediately appear so, at the microscale many of these environments are extremely harsh. Therefore, while many microbes are adapted to survive and even grow in these environments, they will inevitably also experience physiological stresses during their life cycles. As an example, although many microbes can grow in food – resulting in fermentation or spoilage – stress arises from multiple measurable variables including temperature (e.g. heating, freezing) and food components (e.g. acids, salt). A microbial stress can be thought of as any condition that is a departure from optimal conditions. Remarkably, those microbes that do survive exposure to a sublethal stress are often able to tolerate higher levels of that stress, or even a different stress altogether.

The Microbial Stress Response depth study theme allows for a wide range of “jumping off points” for students to develop unique investigations that can be as complex as individual student interest and ability allows. In the design of the program we have carefully selected a matrix of safe microorganisms, stressors and stress responses measurable and able to be manipulated in a standard senior high-school setting. Students can select from and design their own approaches (with near limitless permutations) to the:

  • study of stress responses of microbes representative of different environments including soil, foods, and the human body;
  • study of stress in response to a range of variables, including: temperature, nutrients, atmospheres, and chemicals;
  • study of simultaneous and sequential stress responses;
  • comparison of stress responses of different bacteria – at the genera, species or strain level;
  • comparison of microbial stress response at different microbial population stages.