An efficient artificial esterase with a dynamic conformation via conformational engineering

Wang, Y.; Cao, Y.; Liu, Y.-Y.; Gao, T.; Deng, J.; Zhou, T.; Wang, H.; Cao, A.

doi:10.1101/2025.06.26.661850

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bioRxiv · 10.1101/2025.06.26.661850

An efficient artificial esterase with a dynamic conformation via conformational engineering

Wang, Y.·Cao, Y.·Liu, Y.-Y.·Gao, T.·Deng, J.·Zhou, T.·Wang, H.·Cao, A.

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Abstract

The catalytic turnover number (kcat) of current enzyme mimics and de novo designed enzymes is still orders of magnitude lower than that of natural enzymes, because mimicking the fast-dynamic feature of enzyme active centers remains a great challenge. Herein, we created a gold nanoparticle-based artificial esterase, Goldenzyme, by conformational engineering to reconstruct dynamic active centers resembling that of -chymotrypsin. NMR characterization shows that Goldenzyme possesses a fast-dynamic feature, about 6-fold faster than typical -helix. Therefore, Goldenzyme efficiently hydrolyzes p-nitrophenyl acetate with a net kcat of 6.37 s-1 per active center, more than 5-fold of that of -chymotrypsin (1.19 s-1), and Goldenzyme can even hydrolyze some non-activated esters that -chymotrypsin cannot. Our conformational engineering approach demonstrates the possibility of creating artificial enzymes that surpass natural ones.

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Wang, Y., Cao, Y., Liu, Y.-Y., Gao, T., Deng, J., Zhou, T., Wang, H., Cao, A.. 2025-06-27. An efficient artificial esterase with a dynamic conformation via conformational engineering. https://doi.org/10.1101/2025.06.26.661850

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