Department of Physics and Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Sciences, Tianjin University, 300350, Tianjin, China.
Beijing Synchrotron Radiation Facility (BSRF), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), 100049, Beijing, China.
Nat Commun. 2021 Jan 7;12(1):114. doi: 10.1038/s41467-020-20275-0.
Emerging artificial enzymes with reprogrammed and augmented catalytic activity and substrate selectivity have long been pursued with sustained efforts. The majority of current candidates have rather poor catalytic activity compared with natural molecules. To tackle this limitation, we design artificial enzymes based on a structurally well-defined Au cluster, namely clusterzymes, which are endowed with intrinsic high catalytic activity and selectivity driven by single-atom substitutions with modulated bond lengths. AuCu and AuCd clusterzymes exhibit 137 and 160 times higher antioxidant capacities than natural trolox, respectively. Meanwhile, the clusterzymes demonstrate preferential enzyme-mimicking catalytic activities, with Au, AuCu and AuCd displaying compelling selectivity in glutathione peroxidase-like (GPx-like), catalase-like (CAT-like) and superoxide dismutase-like (SOD-like) activities, respectively. AuCu decreases peroxide in injured brain via catalytic reactions, while AuCd preferentially uses superoxide and nitrogenous signal molecules as substrates, and significantly decreases inflammation factors, indicative of an important role in mitigating neuroinflammation.
新兴的人工酶具有可重新编程和增强的催化活性和底物选择性，长期以来一直受到持续努力的追求。与天然分子相比，目前大多数候选物的催化活性相当差。为了解决这一限制，我们设计了基于结构明确的 Au 团簇的人工酶，即 clusterzymes，其具有内在的高催化活性和选择性，由调制键长的单原子取代驱动。AuCu 和 AuCd clusterzymes 的抗氧化能力分别比天然 trolox 高 137 倍和 160 倍。同时，clusterzymes 表现出优先的酶模拟催化活性，Au、AuCu 和 AuCd 在谷胱甘肽过氧化物酶样 (GPx-like)、过氧化氢酶样 (CAT-like) 和超氧化物歧化酶样 (SOD-like) 活性中表现出强烈的选择性。AuCu 通过催化反应在受损的大脑中减少过氧化物，而 AuCd 优先使用超氧化物和氮信号分子作为底物，并显著降低炎症因子，表明其在减轻神经炎症方面发挥着重要作用。
