The cupredoxin domain 1 of a two-domain laccase related to nitrite reductase
The two-domain laccase (small laccase) in this family differs significantly from all laccases. It resembles the two domain nitrite reductase in both sequence and structure. It consists of two cupredoxin domains and forms trimers and hence resembles the quaternary structure of nitrite reductases more than that of large laccases. There are three trinuclear copper clusters in the enzyme localized between domains 1 and 2 of each pair of neighbor chains. Three copper ions of type 1 lie close to one another near the surface of the central part of the trimer, and, effectively, a trimeric substrate binding site is formed in their vicinity. Laccase is a blue multi-copper enzyme that catalyzes the oxidation of a variety of organic substrates coupled to the reduction of molecular oxygen to water. It displays broad substrate specificity, catalyzing the oxidation of a wide variety of aromatic, notably phenolic, and inorganic substances. Laccase has been implicated in a wide spectrum of biological activities.
Jiyao W et al.(2023). "The conserved domain database in 2023.",