Enhanced Enzyme Activity through Scaffolding on Customizable Self-Assembling Protein Filaments.

Precisely organized enzyme complexes are often found in nature to support complex metabolic reactions in a highly efficient and specific manner. Scaffolding enzymes on artificial materials has thus gained attention as a promising biomimetic strategy to design biocatalytic systems with enhanced productivity. Herein, a versatile scaffolding platform that can immobilize enzymes on customizable nanofibers is reported. An ultrastable self-assembling filamentous protein, the gamma-prefoldin (γ-PFD), is genetically engineered to display an array of peptide tags, which can specifically and stably bind enzymes containing the counterpart domain through simple in vitro mixing. Successful immobilization of proteins along the filamentous template in tunable density is first verified using fluorescent proteins. Then, two different model enzymes, glucose oxidase and horseradish peroxidase, are used to demonstrate that scaffold attachment could enhance the intrinsic catalytic activity of the immobilized enzymes. Considering the previously reported ability of γ-PFD to bind and stabilize a broad range of proteins, the filament's interaction with the bound enzymes may have created a favorable microenvironment for catalysis. It is envisioned that the strategy described here may provide a generally applicable methodology for the scaffolded assembly of multienzymatic complexes for use in biocatalysis.

Engineering bioorthogonal protein-polymer hybrid hydrogel as a functional protein immobilization platform.

We demonstrate the synthesis of protein-polymer hybrid hydrogel that can be used as a platform for immobilizing functional proteins. Orthogonal chemistry was employed for cross-linking the hybrid network and conjugating proteins to the gel backbone, allowing for the convenient, one-pot formation of a functionalized hydrogel. The resulting hydrogel had tunable mechanical properties, was stable in solution, and biocompatible.