Lee, Hyesung Keum, Changjoon Kwon, Choah Kim, Sangtae Jeong, Youngdo Lee, Sang-Yup 2025-08-31T04:00:07Z 2025-08-31T04:00:07Z 2025-08-27 2025-09 https://pubs.kist.re.kr/handle/201004/153087 Single-atom nanozymes (SAzymes) have been developed to mimic metalloenzymes by modulating their coordination environment. However, the impact of the coordination geometry at the metal center on the catalytic activity of the SAzymes, particularly those with nonplanar active site configurations, has been minimally explored. Here, the effects of the geometric configuration of the Zn-N-4 active sites on the catalytic activity of the carbonic anhydrase (CA)-mimetic SAzymes are reported. CA-mimetic SAzymes with Zn-N-4 active sites in tetrahedral, distorted tetrahedral, and square-planar configurations are prepared by simple temperature-controlled carbonization of ZIF-8. The SAzyme with the distorted tetrahedral Zn-N-4 configuration displays superior catalytic CO2 hydration activity, attributed to increased Lewis acidity. Density functional theory (DFT) calculations reveal a pronounced Zn-OH affinity and localized electron accumulation at the distorted tetrahedral Zn site. These results demonstrate the critical role of precise geometric tuning in enhancing SAzyme efficacy and can be used to facilitate potential avenues for optimizing metal active centers in enzyme mimetics. English Wiley-VCH Verlag Coordination Geometry Tuning in a Single-Atom Nanozyme to Mimic Metalloenzymes with Nonplanar Active Site Article 10.1002/advs.202505733 1 Advanced Science, v.12, no.34 Advanced Science 12 34 Y scie scopus 001547135100001 2-s2.0-105012906962 Chemistry, Multidisciplinary Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science Article TRANSITION-METAL IONS CARBONIC-ANHYDRASE RAMAN-SPECTRA MECHANISM MODEL HYDROLYSIS ZINC(II) COMPLEX CO2 DERIVATIVES carbonic anhydrase CO2 coordination geometry hydrolysis single-atom nanozyme