Enzymes are specific to substrates as they have an active site which only allow certain substrates to bind to the active site. This is due to the shape of the active site and any other substrates cannot bind to the active site.

Why is Substrate Specificity important?

Clearly, substrate specificity is an important issue for directed evolution. ... The ability to evolve an enzyme with a high level of a particular activity may depend on finding an enzyme with a low level of activity or an enzyme that acts upon a related substrate.

What defines substrate specificity?

Definition. A feature of enzyme activity with regard to the kind of substrate reacting with an enzyme to yield a product. Supplement. In an enzyme activity, the substrate must bind with the enzyme to become a catalyst of a chemical reaction.