The Enzyme Commission number consists of the letters "EC" followed by four numbers separated by periods, where those numbers represent a progressively finer classification of the enzyme, like the EC 3 where the enzymes are hydrolases and EC 3.4 are hydrolases that act on peptide bonds.
The Enzyme Commission number (EC number) is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. Every enzyme code consists of the letters "EC" followed by four numbers separated by periods. Those numbers represent a progressively finer classification of the enzyme. EC 3 enzymes are hydrolases (enzymes that use water to break up some other molecule) EC 3.4 are hydrolases that act on peptide bonds 
