Name an enzyme that bacteria use to break down hydrogen peroxide.

Bacteria produce the enzyme catalase to break down hydrogen peroxide into water and oxygen. This is a crucial reaction, especially for aerobic bacteria that produce hydrogen peroxide as a byproduct of aerobic respiration. Catalase protects bacterial cells from oxidative damage caused by hydrogen peroxide, which can be harmful if allowed to accumulate.

In contrast, the other enzymes listed serve different functions unrelated to the breakdown of hydrogen peroxide. Oxidase, for example, is involved in the electron transport chain and the oxidation of specific substrates in cellular respiration. Lactase is an enzyme that helps digest lactose, the sugar found in milk, while amylase is involved in starch digestion by breaking down polysaccharides into simpler sugars. Each enzyme has a specific role in metabolism, but catalase is uniquely suited to the detoxification of hydrogen peroxide in bacterial cells.