Site-Specific and Covalent Immobilization of Lipase on Natural Polyphenol-Modified Magnetic Nanoparticles for Effective Biodiesel Production

Abstract

Site-specific and covalent attachment is the most desirable immobilization strategy, but classic methods typically require genetic engineering or complicated material fabrication, resulting in operational complexity and difficulty. Herein, a novel site-specific and covalent immobilization strategy based on accurately selected immobilization sites on lipase was developed. Specifically, computer-aided structural analysis of functional groups on lipase revealed that lysine residues with free amino groups were far away from the catalytic pocket and lid, which were suitable to be chosen as the best immobilization sites to effectively reduce the loss in its activity. Meanwhile, natural polyphenol-modified magnetic nanoparticles could increase the active immobilization sites, and lipase can be immobilized on them directly via a covalent reaction. This site-specific immobilization system exhibited significant enhancement in activity recovery (71.3%) compared to random immobilization (42.5 and 55.9%). As expected, experimental and computational analyses revealed that tailor-made site-specific immobilization carriers were beneficial to maintain the native catalytic pocket conformation and enhance the rigidity of the immobilized lipase, which exhibited a higher biodiesel yield (92.1%) than free and randomly immobilized lipases. Besides, the site-specifically immobilized lipase could maintain as high as 75.3% biodiesel yield after eight cycles, making it an ideal nanocatalyst for efficient production of biodiesel. Overall, the site-specific enzyme immobilization technology can provide stable catalytic activity advantages over the randomly covalent immobilization strategy, which can significantly promote green manufacturing and sustainable production.

The Mesoporous Polydopamine-Based Bowl-like Lipase Nanoreactor for the Biocatalytic Synthesis of Oleate Sterol Ester

“…Because both the spherical and bowl carriers are basically polydopamine, it is clear that their characteristic peaks on the infrared spectral spectrum are similar. There are two peaks in the PDA spectrum for BLM-PDA@CRL at 1644 and 1536 cm –1 , which correlate to the tensile vibrations of the amide I band and amido II band, respectively . The groups on the PDA surface experienced an alteration in their microenvironment due to the successful immobilization of lipase.…”

“…There are two peaks in the PDA spectrum for BLM-PDA@CRL at 1644 and 1536 cm −1 , which correlate to the tensile vibrations of the amide I band and amido II band, respectively. 61 The groups on the PDA surface experienced an alteration in their microenvironment due to the successful immobilization of lipase. The impact of CRL on the absorption of C−O tensile vibration was ascribed to the strong peak that also showed up at 1070 cm −1 .…”

High Enzymatic Activity of CO2 Conversion Achieved by Controllable Enzyme Immobilization and Microenvironment

“…This is analogous to the activity reduction resultant from the accumulation of substrates on the surface, which was reported in previous studies. 60 In addition, the flexible structure of the enzyme in aqueous solution processing might lead to the wrong conformation, which is also responsible for the reduction of recyclability and stability.…”

Research Progress on Lignocellulosic Biomass Degradation Catalyzed by Enzymatic Nanomaterials

“…[102a,104] The method of covalent binding involves chemical bonds, which can make the direct connection between the carrier and the enzyme more solid, greatly reducing enzyme loss and providing repetitive utilization. Chen et al [110] used a covalent immobilization method to immobilize lipase. The activity recovery of the immobilized enzyme (71.3%) was higher than that of random immobilization (42.5% and 55.9%).…”