Lipase Nanogel Catalyzed Transesterification in Anhydrous Dimethyl Sulfoxide

Abstract

The present work showed that Candida rugosa lipase, which is inactive in anhydrous dimethyl sulfoxide (DMSO), has been granted its original catalytic activity and greatly enhanced stability when encapsulated into a polyacrylamide nanogel. The molecular simulation and structural analysis suggested that the polyacrylamide nanogel shielded the extraction of essential water and maintained the native configuration of encapsulated lipase in anhydrous DMSO at an elevated temperature. The electron and fluorescence microscopy showed that the lipase nanogel would be well dispersed in anhydrous DMSO where its native counterpart aggregated. The encapsulated lipase behaved as a stable catalyst for transesterification between dextran and vinyl decanoate in anhydrous DMSO at 60 degrees C for 240 h and yielded a dextran-based polymeric surfactant with regioselectivity toward the C-2 hydroxyl group in the glucopyranosyl unit of dextran. All these indicated a high potential of enzyme nanogel for nonaqueous biocatalysis.

Synthesis of Lutein Esters by Using a Reusable Lipase-Pluronic Conjugate as the Catalyst

“…However, the lipase-catalyzed esterification needs to be carried out in organic solvents in which most enzymes display much lower activities than in aqueous solution mainly due to the formation of agglomeration of the insoluble enzyme molecules in organic solvents making enzyme less accessible to substrates. Nanostructured enzyme catalysts [6][7][8][9] such as enzyme nanoparticles [10,11], enzyme nanogels [12][13][14][15][16][17], flower-like enzyme-inorganic hybrid crystals [18][19][20][21], enzyme-metal-organic framework hybrid composites [22] and enzyme-polymer conjugates [23][24][25] have been demonstrated as effective chemical ways to re-engineer enzyme catalysts for improved activity and stability. For example, conjugation with an amphiphilic polymer such as Pluronic can enhance the solubilization of enzyme in organic solvents and therefore increase the apparent enzymatic activity by orders of magnitudes, as compared to its native counterpart.…”

Enzyme activity in liquid lipase melts as a step towards solvent-free biology at 150 °C

“…Conversely, in non-aqueous media, lipases can use other nucleophiles, such as methanol, to catalyse esterification and transesterification reactions [2][3][4][5][6][7][8][9][10][11][12][13] , although the explicit removal of water is not often a priority. Typically, enzyme reactions performed in organic solvents still contain a hydration layer at the surface of the protein, and the pervasiveness of the solvent in these examples highlights the requirement for a substrate delivery medium [14][15][16][17][18][19][20][21][22][23][24][25] .…”

“…Typically, enzyme reactions performed in organic solvents still contain a hydration layer at the surface of the protein, and the pervasiveness of the solvent in these examples highlights the requirement for a substrate delivery medium [14][15][16][17][18][19][20][21][22][23][24][25] . There have also been reports of lipase catalysis where the reaction proceeds with solvent quantities of one of the reagents 3,12,13 , where the lipases are typically present as either a lyophilized powder 12,13,26 , or immobilized on a substrate 2,3,8,10,27,28 , but there are no examples of molecularly dispersed enzymes catalysing reactions in the complete absence of a solvent.…”

Recent progress in nanobiocatalysis for enzyme immobilization and its application

“…By Fourier transform infrared spectra (FT-IR), the polymer-enzyme conjugate was confirmed [29]. This technique has been used in lipase catalysis for transesterification in anhydrous dimethyl sulfoxide [2], intracellular protein delivery [30], and lipase catalysis for the one-step synthesis of chloramphenicol palmitate [31]. As another example, Lin et al slightly altered the strategy for single enzyme nanogels and aimed to fabricate magnetic enzyme nanogels (MENG) for the encapsulation of both magnetic nanoparticles (MNP) and enzymes within a polymer network, as shown in Fig.…”

“…Not long after, the research focus was shifted toward further characteristics of nanoscale materials, for example, electrical conductivity and magnetism. Consequently, beyond the simple combination of nanoscale support and biocatalysis, a synergetic effect has helped in achieving innovative results such as enzyme stabilization [1], bioconversion in an anhydrous organic solvent [2], the development of biosensors for sensitive detection [3] and biofuel cells for high power density [4], and the development of an electroenzymatic bioconversion system [5,6], as summarized in Table 1.…”