Question

Briefly outline the classification of enzymes

Answer 1

Enzymes are classified into six groups based on their mode of action.

S. No.	Enzymes	Mode of action	General scheme of reaction	Example
1.	Oxidoreductase	Oxidation and reduction (redox) reactions	Ared+Box Aox + B red	Dehydrogenase
2.	Transferase	Transfer a group of atoms from one molecule to another	A-B+C A C B	Transaminase, phosphotransferase phosphotransferase
3.	Hydrolases	Hydrolysis of the substrate by addition of water molecule	A B + H2O A H + B OH	Digestive enzymes
4.	Isomerase	Control the conversion of one isomer to another by transferring a group of atoms from one molecule to another	A B C -- A C B	Isomerase
5.	Lyase	Break chemical bond without the addition of water	A B A B	Decarboxylase
6	Ligase	Formation of new chemical bonds using ATP as a source of energy	A + B + ATP A - B + ADP + Pi	DNA ligase