Chemical Nature

 

 

The enzyme, catalase, is a tetramer composed of four identical subunits each consisting of a single polypeptide chain of 670 amino acids. Each amino acid contains a hydrogen ion, carboxyl group, amino group and a unique R-group. All amino acid have the same overall structure, only differing in their side chain (R-group). The R-group in each of these amino acids gives the enzyme its unique characteristics. Overall, catalase is an organic compound in which carbon atoms are bonded to each other, to hydrogen atoms and nitrogen atoms. The enzyme also contains four porphyrin groups each containing an iron ion connecting each of the four subunits. The iron ion is gripped at the center of a heme group that allows the enzyme to effectively react with hydrogen peroxide.

 

 

A homogenous catalyst is present in the same phase as the molecules of the reactants. For the decomposition of hydrogen peroxide in the human body, catalase is a homogenous catalyst. Catalase is also produced in high quantities in the blood, where oxygen-rich red blood cells produce a lot of hydrogen peroxide. Hydrogen peroxide is found in aqueous form in the human body as it is commonly found in the intercellular and extracellular fluid. As a result, catalase must also be in an aqueous phase in order to carry out its function and help decompose hydrogen peroxide into its component parts.