. Enzyme Catalysis Enzymes are complex protein molecules with three dimensional structures. They catalyse the chemical reaction in living organism. They are often present in colloidal state and extremely specific in catalytic action.
Each enzyme produced in a particular living cell can catalyse a particular reaction in the cell. Some common examples for enzyme catalysis ) The peptide glycyl L-glutamyl L-tyrosin is hydrolysed by an enzyme called pepsin. ) The enzyme diastase hydrolyses starch into maltose (C H O ) +nH O nC H O n ) The yeast contains the enzyme zymase which converts glucose into ethanol. C H O 2C H OH+2CO ) The enzyme micoderma aceti oxidises alcohol into acetic acid.
C H OH+O CH COOH+H O ) The enzyme urease present in soya beans hydrolyses the urea. NH -CO-NH +H O 2NH +CO . . Mechanism of enzyme catalysed reaction The following mechanism is proposed for the enzyme catalysis E+S ES P+E Where E is the enzyme, S the substrate (reactant), ES represents activated complex and P the products.