Conservation of griseofulvin genes in the gsf gene cluster among fungal genomes

The polyketide griseofulvin is a natural antifungal compound and research in griseofulvin has been key in establishing our current understanding of polyketide biosynthesis. Nevertheless, the griseofulvin gsf biosynthetic gene cluster (BGC) remains poorly understood in most fungal species, including Penicillium griseofulvum where griseofulvin was first isolated. To elucidate essential genes involved in griseofulvin biosynthesis, we performed third-generation sequencing to obtain the genome of P. griseofulvum strain D-756. Furthermore, we gathered publicly available genome of 11 other fungal species in which gsf gene cluster was identified. In a comparative genome analysis, we annotated and compared the gsf BGC of all 12 fungal genomes. Our findings show no gene rearrangements at the gsf BGC. Furthermore, seven gsf genes are conserved by most genomes surveyed whereas the remaining six were poorly conserved. This study provides new insights into differences between gsf BGC and suggests that seven gsf genes are essential in griseofulvin production.