Laccase-mimicking enzymes with synergistic amplification effects on catalytic activity for ergothioneine...

In this work, a multimodal analysis strategy for ergothioneine (EGT) with a logical structure was constructed utilizing a novel laccase mimic enzyme (CuPH@KMO). CuPH@KMO demonstrated improved catalytic efficiency and an expanded operational pH range, attributed to synergistic interactions. Firstly, CuPH@KMO with laccase activity could not only catalyze the oxidation of the typical substrates 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP), but also be innovatively employed to oxidize dopamine (DA) and resorcinol (RS) to blue fluorescent azamonardine (Ex = 478 nm) with its absorbance peak located at 420 nm. Then, EGT with reducing and complexing activities could inhibit the CuPH@KMO-catalyzed oxidation of DA and RS, which resulted in the attenuation of both colorimetric and fluorescence signals. Consequently, a multimodal sensing strategy for EGT detection was developed, utilizing CuPH@KMO as the catalytic component, DA and RS as responsive substrates. This method was successfully applied to EGT analysis in cosmetics and dietary supplement. More importantly, a bimolecular logic gate with "AND" and "INHIBIT" had been successfully constructed according to the logical relationship between DA, RS and EGT, which realized the significant process of converting complex data into binary. The implementation of logic sensors based on laccase-mimicking enzymes presents novel opportunities for integrating bioanalysis with logic analysis.