Why do mushrooms have high catalase activity?

Mushrooms have high catalase activity primarily to protect themselves from oxidative stress caused by environmental factors and metabolic processes. Catalase breaks down hydrogen peroxide, a harmful byproduct of cellular respiration, into water and oxygen, thereby preventing cellular damage. This enzymatic defense mechanism allows mushrooms to thrive in diverse habitats where exposure to reactive oxygen species is common. Additionally, their high catalase levels may also play a role in their growth and development.