Cooperative catalysis by a single-atom enzyme-metal complex

Anchoring single metal atoms on enzymes has great potential to generate hybrid catalysts with high activity and selectivity for reactions that cannot be driven by traditional metal catalysts. Herein, we develop a photochemical method to construct a stable single-atom enzyme-metal complex by binding single metal atoms to the carbon radicals generated on an enzyme-polymer conjugate. The metal mass loading of Pd-anchored enzyme is up to 4.0% while maintaining the atomic dispersion of Pd. The cooperative catalysis between lipase-active site and single Pd atom accelerates alkyl-alkyl cross-coupling reaction between 1-bromohexane and B-n-hexyl-9-BBN with high efficiency (TOF is 540 h(-1)), exceeding that of the traditional catalyst Pd(OAc)(2) by a factor of 300 under ambient conditions. Single atom catalysts have been described for efficient and selective metal catalysis, while enzymes have been known for their recognition and binding. In this manuscript, the authors develop a photochemical method to combine the two platforms in one, and demonstrate it by anchoring Pd atoms on Candida Antarctic lipase B, for highly efficient alkyl-alkyl cross-coupling reactions.

Automated summary

This article presents a photochemical method to anchor single metal atoms on enzymes, forming stable single-atom enzyme-metal complexes. The cooperative catalysis between the lipase-active site and the single Pd atom accelerates alkyl-alkyl cross-coupling reactions with high efficiency. This approach combines the advantages of single-atom catalysts and enzymes, potentially leading to hybrid catalysts with high activity and selectivity.