Members of this family have only been identified in species of the Streptomyces genus. Two family members are known to be part of gene clusters involved in the synthesis of polyketide-based spore pigments, homologous to clusters involved in the synthesis of polyketide antibiotics. The function of this protein is unknown, but it has been speculated to contain a NAD(P) binding site [1]. Many of these proteins contain two copies of this presumed domain.

1: Hybridization and DNA sequence analyses suggest an early evolutionary divergence of related biosynthetic gene sets encoding polyketide antibiotics and spore pigments in Streptomyces spp. Blanco G, Brian P, Pereda A, Mendez C, Salas JA, Chater KF; Gene 1993;130:107-116. PMID:8344517