Suppressed Native Hydrolytic Activity of a Lipase to Reveal Promiscuous Michael Addition Activity in Water

• Published in: ChemCatChem
• Main Authors: Svedendahl, Maria, Jovanović, Biljana, Fransson, Linda, Berglund, Per
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2009
• Subjects: Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.1002/cctc.200900041; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fcctc.200900041; http://onlinelibrary.wiley.com/wol1/doi/10.1002/cctc.200900041/fullpdf

Abstract Suppression of the native hydrolytic activity of Pseudozyma antarctica lipase B (PalB) (formerly Candida antarctica lipase B) in water is demonstrated. By replacing the catalytic Ser 105 residue with an alanine unit, promiscuous Michael addition activity is favored. A Michael addition reaction between methyl acrylate and acetylacetone was explored as a model system. For the PalB Ser 105 Ala mutant, the hydrolytic activity was suppressed more than 1000 times and, at the same time, the Michael addition activity was increased by a factor of 100. Docking studies and molecular dynamics simulations revealed an increased ability of the PalB Ser 105 Ala mutant to harbor the substrates close to a catalytically competent conformation.