A novel combination of prosthetic groups in a fungal laccase; PQQ and two copper atoms.
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.
Karhunen
E
E
VTT, Biotechnical Laboratory, Espoo, Finland.
Niku-Paavola
M L
ML
Viikari
L
L
Haltia
T
T
van der Meer
R A
RA
Duine
J A
JA
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*
D010636:Phenols; D015363:Quinolones; D045542:PQQ Cofactor; D003300:Copper; C010559:coniferyl alcohol; D010088:Oxidoreductases; D042845:Laccase; D010100:Oxygen