# Fungal Laccases with High and Medium Redox Potential: Is the T1 Center Potential a Key Characteristic of Catalytic Efficiency in Heterogeneous and Homogeneous Reactions?

## TL;DR

This paper compares fungal laccases with different redox potentials to see how their T1 center potential affects their performance in various reactions.

## Contribution

The study reveals a correlation between T1 center potential and electrocatalytic efficiency but not with homogeneous reactions.

## Key findings

- High-redox-potential laccases (ThL, CcL) showed better electrocatalytic performance.
- No correlation was found between T1 center potential and homogeneous reaction efficiency.
- Structural data was used to interpret the electrocatalytic results.

## Abstract

Catalytic and bioelectrocatalytic properties of four white rot fungal laccases (Trametes hirsuta, ThL; Coriolopsis caperata, CcL; Steccherinum murashkinskyi, SmL; and Antrodiella faginea, AfL) from different orthologous groups were comparatively studied in homogeneous reactions of electron donor substrate oxidation and in a heterogeneous reaction of dioxygen electroreduction. The ThL and CcL laccases belong to high-redox-potential enzymes (E0T1 = 780 mV), while the AfL and SmL laccases are medium-redox-potential enzymes (E0T1 = 620 and 650 mV). We evaluated the efficiency of laccases in mediatorless bioelectrocatalytic dioxygen reduction by the steady-state potential (Ess), onset potential (Eonset), half-wave potential (E1/2), and the slope of the linear segment of the polarization curve. A good correlation was observed between the T1 center potential of the laccases and their electrocatalytic characteristics; however, no correlation with the homogeneous reactions of electron donor substrates’ oxidation was detected. The results obtained are discussed in the light of the known data on the three-dimensional structures of the laccases studied.