The room-temperature e.p.r. spectrum of the Japanese-lacquer-tree (Rhus vernicifera) laccase shows A parallel (the hyperfine splitting constant) and g parallel values of both the Type 1 and Type 2 Cu appreciably different from those measured at liquid-N2 temperature. The geometry of the sites, as inferred from the room-temperature e.p.r. parameters, is more consistent with their redox properties. A rough correlation is found between A parallel and g parallel values and redox potential of the blue copper in several enzymes.
