Installing hydrolytic activity into a completely de novo protein framework

Area of Science:

• Protein engineering
• Biocatalysis
• Structural biology

Background:

• Understanding protein sequence-structure-function relationships is key for designing novel catalysts.
• Enzyme-like catalytic activity is challenging to engineer into artificial protein scaffolds.

Purpose of the Study:

• To predictably install hydrolytic activity into a de novo protein framework.
• To create a thermostable, α-helical barrel protein catalyst.
• To demonstrate the potential of de novo protein design for biocatalysis.

Main Methods:

• Designed and constructed a de novo α-helical barrel protein scaffold.
• Introduced functional polar residues, including cysteine-histidine-glutamic acid triads, into the protein lumen.
• Mutagenesis and characterization of the engineered protein's hydrolytic activity.

Main Results:

• Successfully installed predictable hydrolytic activity into the de novo protein.
• The engineered protein variant exhibited catalytic efficiencies comparable to highly efficient natural hydrolases.
• Demonstrated the incorporation of unnatural side chains to enhance activity and probe mechanisms.

Conclusions:

• This work represents the first report of a functional catalytic triad engineered into a de novo protein framework.
• The developed system provides a predictable and robust method for constructing de novo biocatalysts.
• The engineered protein holds promise for applications in chemical and biochemical synthesis.