What is the Effect of Detergent on Catalase Activity?

Catalase

• The function of catalase within a living organism is to keep hydrogen peroxide from building up in the cell and becoming toxic. Catalase does this by acting as a catalyst for a reaction in which hydrogen peroxide is converted into oxygen gas and water. This conversion reaction would occur on its own, but too slowly to be safe for the organism. Catalase speeds up the process exponentially, as long as nothing occurs to inhibit it.

Enzyme Inhibitors and Activators

• Curare and potassium cyanide are both deadly poisons that operate by inhibiting catalase, slowing down the crucial conversion of hydrogen peroxide to oxygen and water. Detergents and solvents can also have the same effect, by unfolding the structure of the catalase enzyme. When the catalase reaction is inhibited, it can no longer function effectively as a catalyst, and hydrogen peroxide builds up to critical levels in the cells of the body. Other substances also can function as activators, increasing the speed of the reaction beyond what would normally occur from catalase alone.

Denaturation

• The effect of detergent on the catalase reaction can be determined by a denaturation experiment. A solution of Liqui-Nox detergent can be mixed with a catalase extract, using several different concentrations to obtain a range of results. The detergent solution is prepared first, and then the catalase solution is added to it, diluting it to the desired volume. The different concentrations are then compared to determine the results obtained from different amounts of detergent.

Effects on the Peroxisome Membrane

• According to an experiment published in "Histochemical Journal," the addition of detergent to a sample of the peroxisomal or microbody membrane affected the permeability of the membrane to catalase. The experiment found that when the detergent solution was added, the catalase became diffuse. The detergent used was a half-percent or 1 percent solution of Triton X-100. The effects of lipid solvents were also tested, and researchers found that the solvents also acted as inhibitors.