A type 3 multi copper protein. The enzyme, isolated from the bacterium Streptomyces griseus, catalyses an 8 electron oxidation. Activation of the enzyme requires a copper chaperone (GriE). It also acts on 3-amino-4-hydroxybenzaldehyde, giving grixazone A. The second aldehyde group is presumably lost as formate. The enzyme also catalyses the reaction of EC 22.214.171.124 o-aminophenol oxidase.