Artificial Intelligence Platform EnzySFC for Enzyme Screening and Functional Conversion: Completely Redirecting Nitrilase to Nitrile Hydratase Function

Catalytic promiscuity provides fundamental insights into enzyme evolution. To address the multiobjective challenges in discovering and evolving promiscuous activities, we developed EnzySFC, an AI-assisted platform that combines de novo enzyme discovery with functional evolution, enabling coordinated optimization of activity and specificity. Using EnzySFC, we experimentally validated 10 uncharacterized nitrilases from 1113 candidates: 90% showed catalytic activity toward the target substrate, and 80% demonstrated amide formation. Notably, a wild-type nitrilase from a Phototrophicales bacterium exhibited exclusive nitrile hydratase activity. Through AI-driven evolution, 16 mutants of a nitrilase from an Actinomycetia bacterium were experimentally verified within a single prediction cycle. Seven variants displayed increased amide production, five of which exceeded 80% amide proportion. The top four variants achieved a 100% amide yield with complete substrate conversion. This platform establishes a transferable framework for multiobjective enzyme engineering and accelerates the development of efficient enzyme catalysts.