Frames in the class Enzymatic-Reactions describe attributes of an enzyme with respect to a particular reaction. For reactions that are catalyzed by more than one enzyme, or for enzymes that catalyze more than one reaction, multiple Enzymatic-Reactions frames are created, one for each enzyme/reaction pair. For example, Enzymatic-Reactions frames can represent the fact that two enzymes that catalyze the same reaction may be controlled by different activators and inhibitors.