Catalase Physiology, Biochemistry, and Inorganic Mechanism

The video tutorial explains the enzyme catalase, its role in breaking down hydrogen peroxide, and its expression in various cellular locations. It details the structure of catalase, including the heme B coenzyme and critical histidine residue, and describes the biochemical reaction mechanism, highlighting the disproportionation reaction and radical mechanisms involved.

What is the primary function of catalase in cells?

• To store energy

• To synthesize proteins

• To transport oxygen

• To break down hydrogen peroxide

Where is catalase most highly concentrated within the cell?

• Nucleus

• Mitochondria

• Peroxisome

• Golgi apparatus

Which of the following foods can lead to the production of extracellular hydrogen peroxide?

• Nuts

• Vegetables

• Dairy

• Fruits

What is the role of heme B in catalase?

• It transports molecules

• It acts as a substrate

• It is a coenzyme involved in the reaction

• It stores energy

In what oxidation state does iron start in the catalase mechanism?

• 2+

• 3+

• 4+

• 5+

What type of reaction is catalase involved in?

• Hydrolysis

• Disproportionation

• Condensation

• Oxidation

What are the final products of the catalase reaction with hydrogen peroxide?

• Hydrogen and oxygen

• Oxygen and water

• Carbon dioxide and water

• Methane and water

Which residue in the active site of catalase acts as a Bronsted-Lowry acid-base catalyst?

• Serine

• Lysine

• Histidine

• Cysteine

What is the role of radical mechanisms in the catalase reaction?

• To inhibit the reaction

• To bind substrates

• To facilitate electron transfer

• To stabilize the enzyme

What is the significance of regenerating iron in the 3+ state in the catalase mechanism?

• It changes the enzyme's structure

• It releases energy

• It completes the catalytic cycle

• It allows the enzyme to bind more substrates