Bioinformatic analysis of the Yarrowia lipolytica CLIB122 genome has revealed 18 putative lipase genes all of which were expressed in Escherichia coli and screened for hydrolyzing activities against p-nitrophenyl-palmitate. One positive transformant containing an ORF of 1,098 bp encoding a protein of 365 amino acids was obtained. To characterize its enzymatic properties, the lipase gene was functionally expressed in Pichia pastoris. The resulting lipase exhibited the highest activity towards p-NP-decanoate at pH 7 and 35 °C. In addition, the new lipase had a lower optimal temperature and pH compared to other Y. lipolytica lipases. It was noticeably enhanced by Ca(2+), but was inhibited by PMSF, Hg(2+) and Ni(2+). The new lipase displayed the 1,3-specificity for triolein.
© Springer Science+Business Media B.V. 2011