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Updated: Aug 9, 2026

Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
Altering lipase activity and enantioselectivity in organic media using organo-soluble bases: Implication for
Chun-Chi Chen1, Teh-Liang Chen, Shau-Wei Tsai
1Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
Abstract:
With the hydrolytic resolution of (R,S)-naproxen 2,2,2-trifluoroethyl esters via a partially purified papaya lipase (PCPL) in water-saturated isooctane as the model system, the enzyme activity, and enantioselectivty is altered by adding a variety of organo-soluble bases that act as either enzyme activators (i.e., TEA, MP, TOA, DPA, PY, and DMA) or enzyme inhibitors (i.e., PDP, DMAP, and PP). Triethylamine (TEA) is selected as the best enzyme activator as 2.24-fold increase of the initial rate for the (S)-ester is obtained when adding 120 mM of the base. By using an expanded Michaelis-Menten mechanism for the acylation step, the kinetic analysis indicates that the proton transfer for the breakdown of tetrahedral intermediates to acyl-enzyme intermediates is the rate-limiting step, or more sensitive than that for the formation of tetrahedral intermediates when the enzyme activators of different pKa are added. However, no correlation for the proton transfers in the acylation step is found when adding the bases acting as enzyme deactivators.
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