Which enzyme is indicated by the effervescence of hydrogen peroxide when added to bacterial growth?

The effervescence of hydrogen peroxide when added to bacterial growth indicates the presence of catalase. Catalase is an enzyme that catalyzes the breakdown of hydrogen peroxide (H2O2) into water and oxygen gas. When hydrogen peroxide is introduced to a culture containing bacteria that produce catalase, the enzyme reacts with the hydrogen peroxide, resulting in the rapid release of oxygen bubbles, which is observed as effervescence. This characteristic reaction helps differentiate catalase-positive bacteria from those that lack this enzyme.

In contrast, urease is an enzyme that catalyzes the hydrolysis of urease into ammonia and carbon dioxide, and it does not produce bubbles when treated with hydrogen peroxide. Lactase is involved in the hydrolysis of lactose into glucose and galactose, which is unrelated to the breakdown of hydrogen peroxide. Oxidase, on the other hand, refers to a different group of enzymes that participate in oxidation-reduction reactions and does not directly interact with hydrogen peroxide in a way that would cause effervescence. Thus, the presence of effervescence strongly points to the activity of catalase.