title: A novel combination of prosthetic groups in a fungal laccase; PQQ and two copper atoms.
abstract: Extracellular laccase (benzenediol: oxygen oxidoreductase EC 1.10.3.2) from the lignin-degrading fungus, Phlebia radiata, was shown to contain a novel combination of electron carriers as its prosthetic groups. In addition to two copper atoms per enzyme molecule, one molecule of PQQ was included as a cofactor. The EPR spectrum exhibits features of type 1 and type 2 copper atoms. In the enzymatic reaction 4 molecules of lignin model compound, coniferyl alcohol, are oxidized per molecule of oxygen reduced to water. During the reaction coniferyl alcohol is transformed to dilignols.
authors.affiliation: VTT, Biotechnical Laboratory, Espoo, Finland.
authors.forename: E
authors.initials: E
authors.lastname: Karhunen
authors.forename: M L
authors.initials: ML
authors.lastname: Niku-Paavola
authors.forename: L
authors.initials: L
authors.lastname: Viikari
authors.forename: T
authors.initials: T
authors.lastname: Haltia
authors.forename: R A
authors.initials: RA
authors.lastname: van der Meer
authors.forename: J A
authors.initials: JA
authors.lastname: Duine
mesh_terms: D003300:Copper / Q000032:analysis*; D004578:Electron Spin Resonance Spectroscopy; D005658:Fungi / Q000201:enzymology*; D042845:Laccase; D010088:Oxidoreductases / Q000032:analysis*; D010100:Oxygen / Q000378:metabolism; D045542:PQQ Cofactor; D010636:Phenols / Q000378:metabolism; D015363:Quinolones / Q000032:analysis*
chemical_list: D010636:Phenols; D015363:Quinolones; D045542:PQQ Cofactor; D003300:Copper; C010559:coniferyl alcohol; D010088:Oxidoreductases; D042845:Laccase; D010100:Oxygen