Characteristics of Enzymes

Enzymes are bio catalysts produced in the protoplasm. They generally act within the living cell where they have been formed but some time they diffuse out of the cell and act upon some substrate present in the other cells. The enzymes which act within the cell area referred as intra-cellular enzymes or endoenzymes and the other ones are called extra-cellular enzymes or exoenzymes . This basic properties of enzymes are:

• Most of the enzymes area proteinaceous in nature. They are macromolecules (globular proteins) with higher molecular weight. They may entirely consists of protein e.g amylase or pepsin or may contains a non-protein part. They can react with both acidic and alkaline substance due to the presence of protein as the major parts.

• Enzymes are organic catalysts. They only speed up the rate of reaction. They area required in very small quantity, but this small quantity is capable to bring about a change in large amount of substrate. Enzymes are specific in their nature and in their action. It means they react with only particular substrate. Their activities can be accelerated by certain ions or salt called activator e.g Mn, Ni , Mg, Cl, etc. These activator are required in low concentration, some times they function as protectors or anti-inhibitors. Enzymes activity can be inhibited by certain factors e.g substrate concentration, enzymes concentration, pH etc.