In biochemistry, a hydrolase is an enzyme that catalyzes the hydrolysis of a chemical bond. For example, an enzyme that catalyzed the following reaction is a hydrolase:

A–B + H₂O → A–OH + B–H

Nomenclature

Systematic names of hydrolases are formed as "substrate hydrolase." However, common names are typically in the form "substratease." For example, a nuclease is a hydrolase that cleaves nucleic acids.

Classification

Hydrolases are classified as EC 3 in the EC number classification of enzymes. Hydrolases can be further classified into several subclasses, based upon the bonds they act upon:

• EC 3.1: ester bonds (esterases: nucleases, phosphodiesterases, lipase, phosphatase)
• EC 3.2: sugars (glycosylases/DNA glycosylases, glycoside hydrolase)
• EC 3.3: ether bonds
• EC 3.4: peptide bonds (Proteases/peptidases)
• EC 3.5: carbon-nitrogen bonds, other than peptide bonds
• EC 3.6: acid anhydrides (acid anhydride hydrolases, including helicases and GTPase)
• EC 3.7: carbon-carbon bonds
• EC 3.8: halide bonds
• EC 3.9: phosphorus-nitrogen bonds
• EC 3.10: sulfur-nitrogen bonds
• EC 3.11: carbon-phosphorus bonds
• EC 3.12: sulfur-sulfur bonds
• EC 3.13: carbon-sulfur bonds

References

• EC 3 Introduction from the Department of Chemistry at Queen Mary, University of London, only covers 3.1-3.4
• More detailed taxonomy