AAT Bioquest

What are the 6 types of enzymes?

Posted July 22, 2020


Enzymes are classified into six categories according to the type of reaction catalyzed:

  • Oxidoreductases: They catalyze oxidation/reduction reactions by transferring electron from the reductant to the oxidant. NADP or NAD+ are usually used as cofactors by this group of enzymes.
  • Transferases: This class of enzymes transfer specific functional groups (e.g. a methyl or phosphate group) from one molecule to another.
  • Hydrolases: They are responsible of catalyzing the hydrolysis of various chemical bonds, resulting in dividing a large molecule to smaller molecules.
  • Lyases: This type of enzymes catalyzes the cleavage of various chemical bonds by means other than hydrolysis and oxidation, often forming a new double bond or a new ring structure. Lyases require only one substrate for the reaction in one direction, but two substrates for the reverse reaction, which is distinct from other enzymes.
  • Isomerases: Isomerases catalyze isomerization changes within a single molecule, facilitating intramolecular rearrangements in which bonds are broken and formed. The product has the same molecular formula as the substrate but has different bond connectivity or spatial arrangement.
  • Ligases: Ligases catalyze the joining of two molecules by forming a new covalent bond.
Additional resources

Amplite™ Fluorimetric Glucose-6-Phosphate Dehydrogenase (G6PD) Assay Kit

Amplite™ Fluorimetric Coenzyme A Quantitation Kit *Green Fluorescence*

Lodish, H., Berk, A., Kaiser, C. A., Krieger, M., Scott, M. P., Bretscher, A., ... & Matsudaira, P. (2008). Molecular cell biology. Macmillan.

Berg, J. M., Tymoczko, J. L., & Stryer, L. (2008). Biochemistry (Loose-Leaf). Macmillan.