Process for producing gougerotin employing streptomyces microflavus strains

The present invention relates to novel strains of Streptomyces microflavus and methods of their use for controlling diseases or pests of a plant. The invention also relates to a fermentation broth obtained by cultivating a gougerotin producing Streptomyces strain, wherein the fermentation broth contains at least about 1 g/L gougerotin. The invention also relates to a method of producing a fermentation broth of a gougerotin producing Streptomyces strain, wherein the fermentation broth contains at least about 1 g/L gougerotin, the method comprising cultivating the Streptomyces strain in a culture medium containing a digestible carbon source and a digestible nitrogen source under aerobic conditions, wherein the culture medium contains an amino acid at a concentration effective to achieve a gougerotin concentration of at least 1 g/L. The present disclosure also relates to the molecular cloning of a gougerotin biosynthetic gene cluster from Streptomyces microflavus, and identification of individual genes in the gene cluster as well as the proteins encoded thereby. A gougerotin gene cluster comprising 13 open reading frames (ORFs) is located within a genetic locus of Streptomyces microflavus.