Engineering Zinc-Organic Frameworks-Based Artificial Carbonic Anhydrase with Ultrafast Biomimetic Centers for...

Constructing effective and robust biocatalysts with carbonic anhydrase (CA)-mimetic activities offers an alternative and promising pathway for diverse CO₂-related catalytic applications. However, there is very limited success has been achieved in controllably synthesizing CA-mimetic biocatalysts. Here, inspired by the 3D coordination environments of CAs, this study reports on the design of an ultrafast ZnN₃-OH₂ center via tuning the 3D coordination structures and mesoporous defects in a zinc-dipyrazolate framework to serve as new, efficient, and robust CA-mimetic biocatalysts (CABs) to catalyze the hydration reactions. Owing to the structural advantages and high similarity with the active center of natural CAs, the double-walled CAB with mesoporous defects displays superior CA-like reaction kinetics in p-NPA hydrolysis (V₀ = 445.16 nM s^-1, V_max = 3.83 µM s^-1, turnover number: 5.97 × 10^-3 s^-1), which surpasses the by-far-reported metal-organic frameworks-based biocatalysts. This work offers essential guidance in tuning 3D coordination environments in artificial enzymes and proposes a new strategy to create high-performance CA-mimetic biocatalysts for broad applications, such as CO₂ hydration/capture, CO₂ sensing, and abundant hydrolytic reactions.