Characterization of a novel lipolytic enzyme from Aspergillus oryzae

Appl Microbiol Biotechnol. 2013 Jun;97(12):5351-7. doi: 10.1007/s00253-012-4391-7. Epub 2012 Sep 22.

Abstract

In this study, we report the characterization of a protein from Aspergillus oryzae, exhibiting sequence identity with paraben esterase from the genus Aspergillus. The coding region of 1,586 bp, including a 77-bp intron, encoded a protein of 502 amino acids. The gene without the signal peptide of 19 amino acids was cloned into a vector, pPICZαC, and expressed successfully in Pichia pastoris as an active extracellular protein. The purified recombinant protein had pH and temperature optima of 7.0-8.0 and 30 °C, respectively, and was stable at the pH range of 7.0-10.0 and up to 40 °C. The optimal substrate for hydrolysis by the purified recombinant protein, among a panel of α-naphthyl esters (C2-C16), was α-naphthyl butyrate (C4), with activity of 0.16 units/mg protein. The considerable hydrolytic activity of the purified recombinant enzyme toward tributyrin was determined. However, no paraben esterase activity was detected toward the ethyl, propyl, and butyl esters of 4-hydroxybenzoic acid. In addition, no activity was detected toward the methyl esters of ferulic, p-coumaric, caffeic, and sinapic acids that would indicate feruloyl esterase activity.

MeSH terms

  • Amino Acid Sequence
  • Aspergillus oryzae / enzymology*
  • Cloning, Molecular
  • Enzyme Stability
  • Esterases / chemistry
  • Esterases / genetics
  • Esterases / isolation & purification
  • Esterases / metabolism*
  • Gene Expression
  • Hydrogen-Ion Concentration
  • Hydrolysis
  • Molecular Sequence Data
  • Pichia / genetics
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Sequence Alignment
  • Substrate Specificity
  • Temperature
  • Triglycerides / metabolism*

Substances

  • Recombinant Proteins
  • Triglycerides
  • Esterases
  • tributyrin