Molecular Characterization of the Cercosporin Biosynthetic Pathway in the Fungal Plant Pathogen Cercospora nicotianae.

ABSTRACT: Perylenequinones are a class of photoactivated polyketide mycotoxins produced by fungal plant pathogens that notably produce reactive oxygen species with visible light. The best-studied perylenequinone is cercosporin-a product of the Cercospora species. While the cercosporin biosynthetic gene cluster has been described in the tobacco pathogen Cercospora nicotianae, little is known of the metabolite's biosynthesis. Furthermore, in vitro investigations of the polyketide synthase central to cercosporin biosynthesis identified the naphthopyrone nor-toralactone as its direct product-an observation in conflict with published biosynthetic proposals. Here, we present an alternative biosynthetic pathway to cercosporin based on metabolites characterized from a series of biosynthetic gene knockouts.

SUBMITTER: Newman AG 

PROVIDER: S-EPMC5129747 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature