1. Catalase: This enzyme breaks down hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2). Hydrogen peroxide is a toxic byproduct of aerobic respiration, and catalase helps to detoxify it.
2. Superoxide dismutase: This enzyme converts the highly reactive superoxide radical (O2-) into hydrogen peroxide (H2O2) and oxygen (O2). Superoxide radicals are also a byproduct of aerobic respiration and are damaging to cells.
These enzymes are essential for obligate aerobes to survive in an oxygen-rich environment because they protect them from the damaging effects of reactive oxygen species (ROS) generated during aerobic respiration. Anaerobes, on the other hand, lack these enzymes and are therefore sensitive to oxygen and cannot survive in its presence.
