Carbonic Anhydrase‐Mimetic Bolaamphiphile Self‐Assembly for CO2 Hydration and Sequestration

Abstract A biomimetic catalyst was prepared through the self‐assembly of a bolaamphiphilic molecule with histidine moieties for the sequestration of carbon dioxide. The histidyl bolaamphiphilic molecule bis( N ‐α‐amidohistidine)‐1,7‐heptane dicarboxylate has been synthesized and self‐assembled to produce analogues of the active sites of carbonic anhydrase (CA) after association with Zn 2+ ions. Spectroscopic analysis demonstrated the coordination of the Zn 2+ ions with histidine imidazole moieties, which is the core conformation of CA active sites. The Zn‐associated self‐assembly worked as a CA‐mimetic catalyst that shows catalytic activity for CO 2 hydration. Evaluation of the kinetics of using para ‐nitrophenylacetate revealed that the kinetic parameters of the CA‐mimetic catalyst were maximized at the optimal Zn concentration and that excess Zn ions resulted in deteriorated catalytic activity. The performance of the CA‐mimetic catalyst was enhanced by changing the pH value and temperature of the reaction, which implies that the hydrolysis of the substrate is the rate‐determining step. The catalyst‐assisted sequestration of CO 2 was demonstrated by CaCO 3 precipitation upon the addition of Ca 2+ ions. This study offers an easy way to prepare enzyme analogues for CO 2 sequestration through the self‐assembly of bolaamphiphile molecules with designer biochemical moieties.