[Objective] To determine the functions of gou C and gou D in gougerotin biosynthesis, disruption of these two genes was performed. As gougerotin producing strain Streptomyces graminearus lacks efficient genetic manipulation system, the gene cluster for gougerotin biosynthesis was heterologously expressed in Streptomyces coelicolor M1146 to facilitate genetic manipulations of gou C and gou D. [Methods] By using fosmid D6-4H containing the complete gougerotin biosynthetic gene cluster, gou C and gou D were di...