Macromolecules of biological origin perform various functions in the body. For example, proteins which perform the role of biological catalysts in the body are called enzymes , those which are crucial to the communication system in the body are called receptors . Carrier proteins carry polar molecules across the cell membrane . Nucleic acids have coded genetic information for the cell. Lipids and carbohydrates are structural parts of the cell membrane. The drug-target interaction with the examples of enzymes and receptors. The catalytic action of enzymes: For understanding the interaction between a drug and an enzyme, it is important to know how do enzymes catalyse the reaction. In their catalytic activity, enzymes perform two major functions: The first function of an enzyme is to hold the substrate for a chemical reaction . Active sites of enzymes hold the substrate molecule in a suitable position so that it can be attacked by the reagent effectively. Hence, Statement 1 is correct. Substrates bind to the active site of the enzyme through a variety of interactions such as ionic bonding, hydrogen bonding, vander Waals interaction or dipole-dipole interaction The second function of an enzyme is to provide functional groups that will attack the substrate and carry out a chemical reaction. Hence, Statement 2 is correct.
