Reaction: a phenyl acetate + H2O = a phenol + acetate
Other name(s): A-esterase (ambiguous); paraoxonase (ambiguous); aromatic esterase
Systematic name: aryl-ester hydrolase
Comments: Acts on many phenolic esters. The reactions of EC 22.214.171.124 aryldialkylphosphatase, were previously attributed to this enzyme. It is likely that the three forms of human paraoxonase are lactonases rather than aromatic esterases [7,8]. The natural substrates of the paraoxonases are lactones [7,8], with (±)-5-hydroxy-6E,8Z,11Z,4Z-eicostetraenoic-acid 1,5-lactone being the best substrate .
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, UM-BBD, CAS registry number: 9032-73-9
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7. Khersonsky, O. and Tawfik, D.S. Structure-reactivity studies of serum paraoxonase PON1 suggest that its native activity is lactonase. Biochemistry 44 (2005) 6371-6382. [PMID: 15835926]
8. Draganov, D.I., Teiber, J.F., Speelman, A., Osawa, Y., Sunahara, R. and La Du, B.N. Human paraoxonases (PON1, PON2, and PON3) are lactonases with overlapping and distinct substrate specificities. J. Lipid Res. 46 (2005) 1239-1247. [PMID: 15772423]