Free Version

Upgrade subject to access all content


Enzyme Nomenclature


Enzymes are most often referred to by their common names which often, but not always, describes the reaction catalyzed by the enzyme. The E.C. system for enzyme nomenclature is more formal and gives enzymes a series of numbers. An example of an enzyme is glucokinase which catalyzes the reaction shown.

$$\text{glucose} \space +\space ATP\space \xrightarrow [ ]{ } \text{glucose-6-phosphate} \space +\space ADP$$

The designation for this enzyme using the E.C. system is

The first 2 in the E.C. designation refers to the fact that this enzyme

and the 7 refers to the fact that the enzyme


This alone does not completely reveal all of the details of the chemical reaction.

Another detail that can be specified is

and the third number in the E.C. system designates that.