A novel Aspergillus oryzae esterase that hydrolyzes 4-hydroxybenzoic acid esters

Abstract 

In this study we report the biochemical characterization of a hypothetical protein from Aspergillus oryzae exhibiting sequence identity with feruloyl esterase and tannase from the genus Aspergillus. The purified recombinant protein showed a hydrolytic activity toward the ethyl, propyl, or butyl esters of 4-hydroxybenzoic acid, but did not show feruloyl esterase or tannase activity. Finally, the enzyme decreased the antimicrobial activity of parabens against A. oryzae via hydrolysis of the ester bond present in butyl 4-hydroxybenzoic acid.

Abbreviations: MFA, methyl 3-methoxy-4-hydroxycinnamic acid, MCA, methyl 3,4-dihydroxycinnamic acid, MSA, methyl 3,5-dimethoxy-4-hydroxycinnamic acid, MpCA, methyl 4-hydroxycinnamic acid, CGA, chlorogenic acid, HBA, 4-hydroxybenzoic acid, EHBA, ethyl 4-hydroxybenzoic acid, PHBA, propyl 4-hydroxybenzoic acid, BHBA, butyl 4-hydroxybenzoic acid, MDHBA, methyl 3,4-dihydroxybenzoic acid, MTHBA, methyl 3,4,5-trihydroxybenzoic acid

Keywords: Esterase, 4-Hydroxybenzoic acid ester, Paraben, Aspergillus oryzae