Opening Lids: Modulation of Lipase Immobilization by Graphene Oxides

Abstract

Lipases, which can be immobilized and reused for many reaction cycles, are important enzymes with many industrial applications. A key challenge in lipase immobilization for catalysis is to open the lipase lid and maintain it in an open conformation in order to expose its active site. Here we have designed “tailor-made” graphene-based nanosupports for effective lipase (QLM) immobilization through molecular engineering, which is in general a grand challenge to control biophysicochemical interactions at the nano–bio interface. It was observed that increasing hydrophobic surface increased lipase activity due to opening of the helical lid present on lipase. The molecular mechanism of lid opening revealed in molecular dynamics simulations highlights the role of hydrophobic interactions at the interface. We demonstrated that the open and active form of lipase can be achieved and tuned with an optimized activity through chemical reduction of graphene oxide. This research is a major step toward designing nanomaterials as a platform for enhancing enzyme immobilization/activity.

Immobilization of lipases on hydrophobic supports: immobilization mechanism, advantages, problems, and solutions

“…In this regard, it is remarkable that, due to the great flexibility of the active center of lipases (this may be checked comparing the structured of the open and closed forms of lipases in the protein data bank), the features of these enzymes (including activity, selectivity or specificity) have been found to be easily tuned during immobilization (e.g., altering the degree of multipoint covalent attachment, the enzyme orientation or the enzyme environment) (Brem et al, 2012;Chaubey et al, 2006;dos Santos et al, 2015e;Fernandez-Lorente et al, 2008;Fernández-Lorente et al, 2001;Jia Liu et al, 2012;Mathesh et al, 2016;Palomo et al, 2002aPalomo et al, , 2003bRodrigues et al, 2013;Tacias-Pascacio et al, 2017).…”

Synthesis of lutein esters using a novel biocatalyst of Candida antarctica lipase B covalently immobilized on functionalized graphitic carbon nitride nanosheets

“…As an essential participator in the immobilization process, supporting material deeply affects lipase activity. Two-dimensional nanomaterials such as graphene oxide 18 and carbon nanosheets 19,20 have gained extensive attention 21 due to their large surface area, abundant active sites, and good biocompatibility. As a superior material, 2D carbon nitride nanosheets exhibit excellent performance in many elds.…”

Graphene‐Oxide‐Based Enzyme Nanoarchitectonics for Substrate Channeling

“…Graphene is an important 2 D nanomaterial because of its large surface area and ease of biofunctionalization with biomolecules, which can be used as building blocks. Chemically reduced graphene oxide (CRGO) has huge potential to enhance the activity of enzymes upon immobilization . Proteins possess various hydrophobic/hydrophilic groups and could self‐assemble onto molecularly engineered graphenes with different hydrophilic/hydrophobic interfaces to modify their activity.…”