Difference Between Lock And Key Model And Induced Fit Model Of Enzyme Action

The binding of the substrate molecule to the enzyme molecule induces to modify the shape of the active site so that it becomes complementary to the substrate molecule.

Difference between lock and key model and induced fit model of enzyme action. According to this hypothesis the active site does not have a rigid lock and key conformation. Instead the substrate interacts with the active site and both change their shape to fit together. Two main theories are used to explain how enzyme substrate complexes form. Both models depend on the degree of precise binding of the substrate to the active site of the enzyme.

Induced fit and lock and key are the two models which describe the mechanism of action of the enzyme. The way a key the substrate fits into a lock the enzyme. The lock and key model suggests that the substrate is completely complementary in shape to the active site so that it fits in perfectly i e. Enzymes have very precise shape which includes a cleft or pocket called active sites.

Daniel e koshland formulated this hypothesis in 1959. The induced fit model is an elaboration on the basic idea of the lock and key model. Whereas in the lock and key theory the substrate and the active site of the enzyme are complementary in shape at the beginning. The key difference between induced fit and lock and key is that in induced fit theory the binding of the substrate with the active site of the enzyme induces the modification of the shape of the active site into the complementary shape of the substrate.

Similarities between induced fit and lock and key model. They are important in describing how enzymes increase the rate of a biological reaction through catalysis. In this model though the key and the enzyme active site do not fit perfectly together. There is no change in shape of the active site.