The enzyme carboxylesterase (or carboxylic-ester hydrolase, EC 3.1.1.1; systematic name carboxylic-ester hydrolase) catalyzes reactions of the following form:[1]

carboxylesterase
Identifiers
EC no.3.1.1.1
CAS no.9016-18-6
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
Search
PMCarticles
PubMedarticles
NCBIproteins
a carboxylic ester + H2O an alcohol + a carboxylate

Most enzymes from this group are serine hydrolases belonging to the superfamily of proteins with α/β hydrolase fold. Some exceptions include an esterase with β-lactamase-like structure (PDB: 1ci8​).

Carboxylesterases are widely distributed in nature, and are common in mammalian liver. Many participate in phase I metabolism of xenobiotics such as toxins or drugs; the resulting carboxylates are then conjugated by other enzymes to increase solubility and eventually excreted. The essential polyunsaturated fatty acid arachidonic acid (AA C20H32O2; 20:4, n-6), formed by the synthesis from dietary linoleic acid (LA: C18H32O2 18:2, n-6), has a role as a human carboxylesterase inhibitor.[2]

The carboxylesterase family of evolutionarily related proteins (those with clear sequence homology to each other) includes a number of proteins with different substrate specificities, such as acetylcholinesterases.

Examples

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The last enzyme also participates in alkaloid biosynthesis.

Genes

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Humans genes that encode carboxylesterase enzymes include:

An approved nomenclature has been established for the five mammalian carboxylesterase gene families.[3]

References

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  1. ^ Aranda, Juan; Cerqueira, N. M. F. S. A.; Fernandes, P.A.; Roca, M.; Tuñon, I.; Ramos, M. J. (2014). "The Catalytic Mechanism of Carboxylesterases. A Computational Study". Biochemistry. 53 (36): 5820–5829. doi:10.1021/bi500934j. PMID 25101647.
  2. ^ PubChem. "Arachidonic acid". pubchem.ncbi.nlm.nih.gov. Retrieved 2022-11-24.
  3. ^ Holmes RS, Wright MW, Laulederkind SJ, Cox LA, Hosokawa M, Imai T, Ishibashi S, Lehner R, Miyazaki M, Perkins EJ, Potter PM, Redinbo MR, Robert J, Satoh T, Yamashita T, Yan B, Yokoi T, Zechner R, Maltais LJ (2010). "Recommended nomenclature for five mammalian carboxylesterase gene families: human, mouse, and rat genes and proteins". Mamm. Genome. 21 (9–10): 427–41. doi:10.1007/s00335-010-9284-4. PMC 3127206. PMID 20931200.

Further reading

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