The first cupredoxin domain of fungal laccases similar to Tv-LCC from Trametes versicolor
This subfamily of fungal laccases includes Tv-LCC from Trametes versicolor and Rs-LCC2 from plant pathogenic fungus Rhizoctonia solani. Laccase is a blue multi-copper enzyme that catalyzes the oxidation of a variety aromatic - notably phenolic and inorganic substances coupled to the reduction of molecular oxygen to water. It has been implicated in a wide spectrum of biological activities and, in particular, plays a key role in morphogenesis, development and lignin metabolism. Although MCOs have diverse functions, majority of them have three cupredoxin domain repeats that include one mononuclear and one trinuclear copper center. The copper ions are bound in several sites: Type 1, Type 2, and/or Type 3. The ensemble of types 2 and 3 copper is called a trinuclear cluster. MCOs oxidize their substrate by accepting electrons at a mononuclear copper center and transferring them to the active site trinuclear copper center. The cupredoxin domain 1 of 3-domain MCOs contains part the trinuclear copper binding site, which is located at the interface of domains 1 and 3.
Feature 1: trinuclear Cu binding site [ion binding site], 4 residue positions
Conserved feature residue pattern:H H H H
Evidence:
Structure:1GYC; trinuclear copper binding center of Laccase From Trametes versicolor, contacts at 4A.
Comment:The trinuclear center is located at the interface of two cupredoxin domains. A dioxygen is reduced to two molecules of water by accepting four electrons. The three coppers are coordinated by eight Histidine residues from two cupredoxin domain.