430d Lipase Nanogel for Nonaqueous Biocatalysis

Ge Jun, Lu Diannan, Wang Jun, and Liu Zheng. Chemical Enigeering, Tsinghua University, Beijing, China

Lipase from Candida rugosa was prepared as nanogels with diameters around 30 nm by in situ polymerization using acrylamide as monomers. The lipase nanogel preserves over 90% of the initial activity while showed an essentially identical catalytic behavior to its native counterpart. The lipase nanogel remains its initial activity after 10 hour incubation at 50 °C while its native counterpart lost 50% activity within 50 min. The encapsulation also let to a significant enhancement in the tolerance to anhydrous dimethylsulfoxide (DMSO), dimethylformamide (DMF) and methanol.

Also included in the presentation was the assembly of monomer around enzyme as the essential step in the aqueous in situ synthesis of the lipase nanogel, as illustrated by molecular dynamic simulation and fluorescence resonance energy transfer spectrum using lipase/acrylamide as a model system. Application of the lipase was exemplified by the production of biodiesel, the esterification of ibuprofen and the synthesis of polysaccharide esters. It is concluded from above simulation and experiments that the nanogel provides a robust enzyme module for a full display of the biological power of enzymes.