Multifaceted fullerene-based enzyme mimics of tyrosinase: From catalysis to bioactivity and biosensing

Tyrosinase, an enzyme capable of oxidizing a broad range of substrates, is used in many important fields such as medicine, environmental technologies, and energy production. However, the drawbacks of tyrosinase, including low stability, high production costs, and complex production processes, limit its use and to date, no enzyme mimic has replicated the catalytic mechanism of tyrosinase with sufficiently high activity for practical applications. Here, we present a self-assembled fullerene-based nanocatalyst system (Cu-TYR^m) containing copper-coordinated histidine amino acids with multifaceted functions. First, the system exhibits high catalytic activity for the oxidation of L-tyrosine and L-DOPA to melanin, following Michaelis-Menten kinetics. Moreover, it stands out as a closely related analog to the tyrosinase enzyme in terms of active-site structure and catalysis. Second, these Cu-TYR^m nanocatalysts demonstrate tyrosinase-like biological activity and mimic various metabolic functions of tyrosinase, including ROS scavenging. Finally, they serve as substitutes for natural tyrosinase in biosensor applications, offering enhanced biosensing ability, exceptional reusability, and high stability.