What happens to an enzyme after it catalyzes a chemical reaction?
Enzymes are not used up in a chemical reaction. Usually, the
enzyme will "reset" and be ready to use in another reaction. This
is due to the fact that enzymes are proteins, and their shape is
what they use in a chemical reaction. Initially, the enzyme has a
particular shape. Something happens to the enzyme (usually a shape
change, called a conformation change, brought on by the presence of
two or more chemical reactants), and the enzyme catalyzes the
reaction. After the reaction is catalyzed, the product is released,
and the enzyme can "relax." This means it goes back to its normal
shape, ready to do it all over again.