The key difference between catalase and peroxidase is that catalase catalyzes the decomposition of hydrogen peroxide into water and oxygen, whereas peroxidase catalyzes the decomposition of peroxides.
Catalase and peroxidase are common enzymes. An enzyme is a biological component that is important in catalyzing chemical reactions by reducing the activation energy barrier of the reaction. Therefore, an enzyme can enhance the rate of that particular chemical reaction.
What is Catalase?
Catalase is a common enzyme found in organisms and is important in decomposing hydrogen peroxide to form water and oxygen. We can find this enzyme nearly in all the living beings that are exposed to oxygen. E.g. bacteria, plants, animals, etc. Therefore, this enzyme is very important in protecting our body from the oxidative damage by reactive hydrogen species that are formed from hydrogen peroxide.
When considering the chemical structure of catalase, it is a tetramer. That means, this enzyme molecule contains four polypeptide chains. Each polypeptide chain is about 500 amino acids long. There is a collection of four iron-containing heme groups that are important in the decomposition of hydrogen peroxide. For this enzyme, the optimum pH level inside the human body is pH 7. However, the rate of the reaction does not change much if the pH ranges between 6.8 and 7.5. In addition, the optimum temperature varies according to the animal species.
Most organisms use catalase enzymes in every organ they have. Generally, the liver contains a high concentration of catalase, especially in mammals. Primarily, it occurs in peroxisomes and cytosol of erythrocytes. Moreover, this enzyme is extracted and used in the food industry for the removal of hydrogen peroxide from milk prior to cheese production. In addition to that, it is useful in food wrappers to prevent food from oxidizing.
What is Peroxidase?
Peroxidase is a common enzyme that is important in decomposing peroxide compounds. It is also named as peroxide reductase. In addition to the decomposition of peroxides, there are other biological processes that use this enzyme for proper function. For example, peroxides are important in the treatment of industrial wastewater, to convert toxic substances into less harmful substances, to and polymerize anilines and phenols. They are sometimes used as histological markers, as well.
For most chemical reactions that involve the peroxidase enzyme, the optimal substrate is hydrogen peroxide. However, this enzyme is more active than other substrates such as organic hydroperoxides, e.g. liquid peroxides.
What is the Difference Between Catalase and Peroxidase?
Catalase and peroxidase are enzymes. The key difference between catalase and peroxidase is that catalase catalyzes the decomposition of hydrogen peroxide into water and oxygen, whereas peroxidase catalyzes the decomposition of peroxides. Therefore, catalase is a type of peroxidase enzyme. Moreover, the optimum substrate for a peroxidase is hydrogen peroxide, which is the substrate for catalase enzyme.
The following infographic summarizes the differences between catalase and peroxidase in tabular form.
Summary – Catalase vs Peroxidase
An enzyme is a biological component that can enhance the rate of a chemical reaction by reducing the activation energy barrier. Catalase and peroxidase are enzymes. The key difference between catalase and peroxidase is that catalase catalyzes the decomposition of hydrogen peroxide into water and oxygen, whereas peroxidase catalyzes the decomposition of peroxides.
1. “Catalase.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 27 Dec. 2017, Available here.
1. “Hydrogen-peroxide-2D” Public Domain) via Commons Wikimedia
2. “GlutPeroxidase-1GP1” By http://en.wikipedia.org/wiki/User:Jag123 – http://en.wikipedia.org/wiki/Image:GlutPeroxidase-1GP1.png (Public Domain) via Commons Wikimedia