Construction of Aspergillus niger lipase mutants with oil-water interface independence

Enzyme Microb Technol. 2011 Feb 8;48(2):129-33. doi: 10.1016/j.enzmictec.2010.10.011. Epub 2010 Nov 9.

Abstract

Based on previous bioinformational analytical results [Shu ZY, et al. Biotechnol Prog 2009;25:409-16], four A. niger lipase (ANL) mutants, ANL-Ser84Gly, ANL-Asp99Pro, ANL-Lys108Glu and ANL-EαH (obtained by replacing the lid domain of ANL with the corresponding domain from A. niger feruloyl esterase), were constructed to screen out ANL mutants with oil-water interface independence. ANL-S84G displayed a pronounced interfacial activation, while ANL-D99P and ANL-K108E displayed no interfacial activation. The specific activity of ANL-S84G towards p-nitrophenyl esters decreased from 29.8% to 76.5% compared with that of ANL, while the specific activity of ANL-D99P towards p-nitrophenyl palmitate increased 2.2-fold. The thermostability of ANL-K108E was almost unchanged, while the thermostability of ANL-S84G and ANL-D99P significantly decreased compared with that of ANL. The construction of oil-water interface-independent ANL mutants would help to further understand the mechanism of lipase interfacial activation.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Aspergillus niger / enzymology*
  • Aspergillus niger / genetics*
  • Enzyme Activation
  • Enzyme Stability
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Lipase / genetics*
  • Lipase / metabolism
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed*
  • Mutation / genetics*
  • Oils
  • Pichia / genetics
  • Pichia / metabolism
  • Polymerase Chain Reaction
  • Structure-Activity Relationship
  • Substrate Specificity
  • Water

Substances

  • Fungal Proteins
  • Oils
  • Water
  • Lipase