Question

The binding of the substrate induces the enzyme to alter its shape fitting more tightly around the substrate.

Answer 1

Induced fit indicates a continuous change in the conformation and shape of an enzyme in response to substrate binding. This makes the enzyme catalytic which results in the lowering of the activation energy barrier causing an increase in the overall rate of the reaction. In other words, when a substrate binds to an enzyme, it will change the conformation of the enzyme. This forms a transitional intermediate which lowers the activation energy and allows the reactants to proceed towards the product at a faster rate. In the case of macromolecules (e.g. proteins), induced fit shows the changes in the shape of a macromolecule in response to a ligand binding so that the binding site of macromolecule conforms more efficiently to the shape of the ligand. The enzyme will change its shape until it is completely complementary to a substrate to activate the enzyme-substrate complex.