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 3.1.8.1 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 [8].
Links to other databases: BRENDA, EAWAG-BBD, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9032-73-9
References:
1. Aldridge, W.N. Serum esterases. I. Two types of esterase (A and B) hydrolysing p-nitrophenyl acetate, propionate and butyrate and a method for their determination. Biochem. J. 53 (1953) 110-117. [PMID: 13032041]
2. Augustinsson, K.-B. and Olsson, B. Esterases in the milk and blood of swine. I. Substrate specificity and electrophoresis studies. Biochem. J. 71 (1959) 477-484. [PMID: 13638253]
3. Bosmann, H.B. Membrane marker enzymes. Characterization of an arylesterase of guinea pig cerebral cortex utilizing p-nitrophenyl acetate as substrate. Biochim. Biophys. Acta 276 (1972) 180-191. [PMID: 5047702]
4. Kim, D.-H., Yang, Y.-S. and Jakoby, W.B. Nonserine esterases from rat liver cytosol. Protein Expr. Purif. 1 (1990) 19-27. [PMID: 2152179]
5. Mackness, M.I., Thompson, H.M., Hardy, A.R. and Walker, C.H. Distinction between 'A'-esterases and arylesterases. Implications for esterase classification. Biochem. J. 245 (1987) 293-296. [PMID: 2822017]
6. Reiner, E., Aldridge, W.N. and Hoskin, C.G. (Eds.) Enzymes Hydrolysing Organophosphorus Compounds, Ellis Horwood, Chichester, UK, 1989.
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]