Hydrolases

Hydrolases
Enzyme classification
EC, category	3.-.-.-
Response type	hydrolysis
Substrate	${\displaystyle \mathrm {A{-}B+H_{2}O} }$
Products	${\displaystyle \mathrm {A{-}H+B{-}OH} }$
Occurrence
Parent taxon	Creature

Hydrolases are enzymes which hydrolytically split esters , ethers , peptides , glycosides , acid anhydrides or CC bonds in a reversible reaction . They form the third group of the EC enzyme classification. Their representatives include peptidases , nucleases , phosphatases , glycosidases and esterases .

The catalyzed equilibrium is

${\displaystyle \mathrm {A{-}B+H_{2}O\leftrightharpoons A{-}H+B{-}OH} }$

classification

In the internationally recognized EC classification of enzymes, the hydrolases form group 3. Then hydrolases are further subdivided depending on which type of bond is split:

number	binding	Group name	example
EC  3.1.-.-	Ester bond	Esterases	Lipase Nuclease Phosphatase Sulfatase
EC  3.2.-.-	Glycoside bond	Glycosylases	Amylase Glycosidases
EC  3.3.-.-	Ether linkage
EC  3.4.-.-	Peptide bond	Peptidases	Exopeptidase Endopeptidase
EC  3.5.-.-	CN bond (without peptide)	Amidases	Urease
EC  3.6.-.-	Acid anhydride bond		Pyrophosphatase
EC  3.7.-.-	CC bond		Kynureninase
EC  3.8.-.-	Halogen bond
EC  3.9.-.-	PN binding
EC  3.10.-.-	SN bond
EC  3.11.-.-	CP binding
EC  3.12.-.-	SS binding
EC  3.13.-.-	CS bond

Well-known examples

ATPase ATP synthase Carboxypeptidase Chymotrypsin Deoxyribonuclease (DNAse)

Lactase pepsin Trypsin Urease

Other classes of enzymes

• Oxidoreductases ( EC  1.-.-.- )
• Transferases ( EC  2.-.-.- )
• Lyases ( EC  4.-.-.- )
• Isomerases ( EC  5.-.-.- )
• Ligases ( EC  6.-.-.- )

See also

• hydrolysis
• Alcoholysis

Individual evidence

1. ^ Albert Gossauer: Structure and reactivity of biomolecules , Verlag Helvetica Chimica Acta, Zurich, 2006, p. 450, ISBN 978-3-906390-29-1 .
2. ↑ Overview of the hydrolase nomenclature (English, accessed on August 4, 2020)