(a) Oxidoreductase/Dehydrogenase : Enzymes that catalyses oxidoreduction between two substrates.
(b) Transferases : Enzyme that catalyses transfer of a group from one substrate to another.
(c) Hydrolases : Enzyme that catalyses hydrolysis of ester, ether, peptide, C–C, C–halide or P–N glycosidic bonds.
(d) Lyases : Enzymes that catalyse removal of groups by mechanism other than hydrolysis leaving double bond.
(e) Isomerases : Enzymes that catalysis the arrangement of atoms in a molecule to from its isomer.
(f) Ligases : Catalyse linking together of two compounds