By putting the suffix -ase at the end.
"protease"; an enzyme that breaks down proteins
The name of an enzyme typically indicates its substrate or the type of reaction it catalyzes. Enzyme names often end in "-ase" to show that it is an enzyme. Additionally, the name may provide information about the enzyme's source or origin, such as "pepsin" from the stomach.
The suffix -ase indicates an enzyme, e.g. proteinase, dehydrogenase, hydrogenase, polymerase.
Typically, any macro-biomolecule whose name ends with the suffix -ase is an enzyme.
There is no enzyme by the name "fructase." However, an enzyme called fructosidase catalyzes the hydrolysis of fructose-containing compounds.
Usually an enzyme is named after it's function.
The suffix -ase indicates an enzyme, e.g. proteinase, dehydrogenase, hydrogenase, polymerase.
Part of an enzyme's name is usually derived from the reaction it catalyzes.
The enzyme that activates another enzyme is called a kinase. Kinases add phosphate groups to proteins, a process known as phosphorylation, which can activate or deactivate the target enzyme.
The enzyme responsible for gelatin hydrolysis is gelatinase.
The enzyme that digests proteins into peptides is called protease.
The enzyme that breaks down starch is called amylase.