Scytalone dehydratase involved the biosynthesis of dihydroxynaphthalene (DHN)-melanin, a bluish-green pigment forming a dark layer in the conidial wall that protects the conidia from UV radiations (PubMed:28517364). The first step of the pathway is the production of the pentaketide 1,3,6,8-tetrahydroxynaphthalene (1,3,6,8-THN or T4HN) by the polyketide synthase PfmaE though condensation of acetyl-CoA with malonyl-CoA. T4HN is not stable and easily oxidizes into the stable form flaviolin (PubMed:28517364). T4HN is also substrate of the hydroxynaphthalene reductase PfmaG to yield scytalone (PubMed:28517364). The scytalone dehydratase PfmaJ then reduces scytalone to 1,3,8-THN (PubMed:31116900). 1,3,8-THN is then substrate of the hydroxynaphthalene reductase PfmaI to yield vermelone (Probable). Vermelone is further converted by the multicopper oxidase PfmaD to 1,8-DHN (Probable). Finally the laccase PFICI_06862 transforms 1,8-DHN to DHN-melanin (Probable). The roles of the 5-oxoprolinase PfmaA and the proline iminopeptidase PfmaB within the cluster have not been elucidated yet (Probable). scytalone = 1,3,8-trihydroxynaphthalene + H2O Pigment biosynthesis; melanin biosynthesis. Homotrimer (By similarity). Each subunit contains an active site, located in the central part of the hydrophobic core of the monomer, which functions independently (By similarity). Expression is positively regulazed by the cluster-specific transcription factor pfmaF. Belongs to the scytalone dehydratase family.