Describe the important properties of enzymes.

Properties of enzymes
 Enzymes are complex macromolecules with high molecular weight.
 They catalyze biochemical reactions in a cell. They help in the breakdown of large molecules into smaller molecules or bring together two smaller molecules to form a larger molecule.
 Enzymes do not start a reaction. However, they help in accelerating it.
 Enzymes affect the rate of biochemical reaction and not the direction. (5) Most of the enzymes have high turnover number. Turnover number of an enzyme is the number of molecules of a substance that is acted upon by an enzyme per minute. High turnover number of enzymes increases the efficiency of reaction.
 Enzymes are specific in action.
 Enzymatic activity decreases with increase in temperature.
 They show maximum activity at an optimum pH of 6 – 8.
 The velocity of enzyme increases with increase in substrate concentration and then, ultimately reaches maximum velocity.

Enzymes are biological catalysts. No metabolic reaction takes place without an enzyme. Enzymes are highly specific to the substrates. Unlike inorganic catalysts, enzymes are susceptible to high temperatures and cease to act after optimum temperature. Enzymes greatly hasten the rate of metabolic reactions.

Properties of enzymes

• An enzyme like any protein has primary structure (amino acid sequence). Secondary structure and tertiary structure
• Every enzyme has an ’active site’ which is a crevice into which the substrate fits.
• Enzymes are specific in their action. Particular enzyme acts on a particular substrate. But different enzymes catalyse a unique chemical or metabolic reaction.
• Enzymes generally function in a narrow range of temperature and pH. Activity declines both below and above optimum temperature and pH.
• The higher the affinity of the enzyme for its substrate the greater is its catalytic activity.
• The activity of an enzyme is also sensitive to the presence of specific chemicals that bind to the enzyme.
• For eg: Inhibitors that shuts off enzyme activity and Co-factors that facilitates catalytic activity.
• Enzymes retain their identity at the end of the reaction