Dual functionality of a waste-derived artificial enzyme: organophosphate degradation and DNA cleavage

Pursuing artificial enzymes through materials engineering allows mimicking the high reactivity of natural enzymes while attaching new and desirable properties to the final material. For this, the use of biopolymers – including from waste – as precursors stands out due to their biocompatible features, harmlessness, easy handling, and low cost. Herein, we repurposed Black Wattle gum, an industrial waste from the tannin industry, into an imidazole-functionalized biocatalyst for dephosphorylation reactions. The obtained sample, GNAIMZ, was fully characterized by colorimetric assays, carbon-13 nuclear magnetic resonance, and potentiometric titrations, proving the chemical modification proposed. Then, GNAIMZ was evaluated with organophosphate simulant diethyl 2,4-dinitrophenylphosphate (DEDNPP) and real pesticide Paraoxon, unveiling rate enhancements up to 107-fold compared to the reaction in the absence of biocatalyst. At last, GNAIMZ was applied in DNA cleavage assays, unraveling a nuclease-like activity leading to total degradation of plasmid DNA at pH 7.5 for 12 hours. Overall, this study showcases the successful valorization of a waste-derived gum into a dual-function artificial enzyme for dephosphorylation reactions capable of neutralizing toxic organophosphates and promoting DNA cleavage, reinforcing the promising features of biopolymers as scaffolds for synthetic enzymes – even from byproducts – pursued to chemical security and genetic engineering.

Key words
gum arabic; biocatalyst; organophosphorus compounds; neutralization; functionalization