A supramolecular metalloenzyme possessing robust oxidase-mimetic catalytic function

Abstract

Enzymes fold into unique three-dimensional structures to distribute their reactive amino acid residues, but environmental changes can disrupt their essential folding and lead to irreversible activity loss. The de novo synthesis of enzyme-like active sites is challenging due to the difficulty of replicating the spatial arrangement of functional groups. Here, we present a supramolecular mimetic enzyme formed by self-assembling nucleotides with fluorenylmethyloxycarbonyl (Fmoc)-modified amino acids and copper. This catalyst exhibits catalytic functions akin those of copper cluster-dependent oxidases, and catalytic performance surpasses to date-reported artificial complexes. Our experimental and theoretical results reveal the crucial role of periodic arrangement of amino acid components, enabled by fluorenyl stacking, in forming oxidase-mimetic copper clusters. Nucleotides provide coordination atoms that enhance copper activity by facilitating the formation of a copper-peroxide intermediate. The catalyst shows thermophilic behavior, remaining active up to 95 °C in an aqueous environment. These findings may aid the design of advanced biomimetic catalysts and offer insights into primordial redox enzymes.

Oxidase-Mimetic Nanocatalyst Based on Geometry-Dependent Biomolecular Self-Assembly

“…We have previously demonstrated the self-assembly of Fmoc-K through fluorenyl-fluorenyl stacking, leading to the formation of ordered structures that facilitate the creation of dicopper sites. 24 In this work, we employed X-ray absorption spectroscopy (XAS) to examine the obtained spectra of the copper-containing complexes. Interestingly, the 1s → 3d transition peak observed in the XAS spectra of the FAD/ Fmoc-K/Cu 2+ complex exhibited remarkable similarity to that of Fmoc-K/Cu 2+ , indicating comparable coordination structures of copper (Figure 2D).…”

“…Recent studies have shown that the self-assembly of nucleotides with amino acid−based amphiphile aggregates can create a catechol oxidase-like coordination sphere for copper ions. 24 In these studies, the heterogeneous components that comprise the supramolecular catalysts' scaffolds act synergistically in cofactor activation (hemin or Cu 2+ ). However, they do not have well-defined interactions like those in natural multimeric systems, leading to reduced cooperation between the components and poorly resolved active site structures.…”

A designed DNA/amino acid amphiphile-based supramolecular oxidase-mimetic catalyst for colorimetric DNA detection

“…21 Such aggregation of Fmoc-K also resulted in the formation of an unsaturated dicopper site. 16 The addition of ssDNA or dsDNA did not alter the fluorescence spectra of Fmoc-K (Fig. 3a and Fig.…”

“…, Fmoc-lysine (Fmoc-K), Fmoc-histidine (Fmoc-H), Fmoc-arginine (Fmoc-R)) can self-assemble through aromatic stacking of the fluorenyl moiety, to create a catechol oxidase-mimetic coordination sphere for dicopper sites. 16 The introduction of nucleotides, such as guanosine monophosphate, can significantly enhance the activity of Fmoc-amino acids/Cu 2+ . This improvement is attributed to the role of the nitrogen atoms present in the nucleobases, which effectively modify the catalytic microenvironment of copper.…”

Lanthanide complexes facilitate wound healing by promoting fibroblast viability, migration and M2 macrophage polarization

“…Metal-based inorganic material are essential catalytic and structural elements of some (metallo)enzymes. 6 In the field of medicinal chemistry, metal complexes have been used as potential therapeutic agents for treating various kind of diseases. 7 They can inhibit or increase their expression level and activity through conformational changes.…”